JP7616564B2 - Heat transfer coefficient measuring device and method - Google Patents

Description

The present invention relates to a thermal transmission coefficient measuring device and method that can measure the thermal transmission coefficient even if the surface shape of the measurement range of the object to be measured for thermal insulation performance is flat, curved, or has three-dimensional changes.

Non-Patent Document 1 describes the calibrated heat box method and the protected heat box method as methods for measuring the thermal insulation of building components. In the protected heat box method, a heating box is placed inside a protected heat box, which is controlled to minimize the amount of heat loss parallel to the surface of the test piece and the amount of heat loss from the surrounding walls of the heating box, and the amount of heat passing through the test piece is measured based on the amount of heat supplied to the heating box. However, it is difficult to measure in an ideal state where the amount of heat loss parallel to the surface of the test piece and the amount of heat loss from the surrounding walls of the heating box are both zero. Therefore, the calibrated heat box method, which is an improvement on the protected heat box method, discloses a technology that measures the amount of heat passing through the test piece by subtracting the amount of heat loss parallel to the surface of the test piece and the amount of heat loss from the surrounding walls of the heating box from the amount of heat supplied to the heating box.

As described in "8.3 Thermopile," the thermopile is used to monitor the heat flow around the heating box wall, and "8.5 Temperature Control" states that the fluctuation in air temperature in the heating box, protective heat box, and cooling chamber should be within 1% of the air temperature difference on both sides of the test specimen over two consecutive measurement periods. On the other hand, as described in "5.2 Calibration Hot Box Method," the entire device for the calibration hot box method is placed in a constant temperature room. "7.2.1 Box Structure" states that the heating box is attached to the test specimen with an airtight material.

Non-patent document 2 describes a method for testing the thermal insulation of building materials, and as shown in "Figure 3: Calibrated heat box method test device (cross section)", a test specimen is placed at the boundary between a high-temperature room and a low-temperature room, and a heat box is placed on the high-temperature room side of the test specimen, and the test specimen is constructed in accordance with the provisions of Japanese Industrial Standard JIS A1420, and the thermal transmittance of the test specimen is measured in accordance with the provisions.

Patent Document 1 discloses an automatic heat transfer coefficient measuring device for a refrigerated vehicle body that calculates the heat transfer coefficient from the dimensions of the refrigerated vehicle body, such as the external dimensions, temperature information such as the temperature inside the refrigerated vehicle body, and a heater voltage transducer that detects the voltage of a heat transfer heater installed inside the refrigerated vehicle body as a digital quantity.

Japanese Patent Application Publication No. 2-272334

Japanese Industrial Standards JIS A1420 Japanese Industrial Standards JIS A4710

Improved insulation performance of automobile interiors is required to improve the efficiency of air conditioning performance and fuel economy in automobiles such as hybrid cars and electric cars. Therefore, there is a demand for a method that can easily evaluate the insulation performance of each part that forms the surrounding walls of the interior of an automobile where passengers sit, such as the back door, front door, rear door, or roof.

In Non-Patent Document 1, as shown in FIG. 5(a), the thermal conductivity is calculated from the amount of heat passing from one surface of the test piece 25 in contact with the high temperature side in the thickness direction to the other surface in contact with the low temperature side, by dividing the amount of heat passing through the test piece Φ1 by the product of the area A perpendicular to the heat flow of the test piece 25 and the value obtained by subtracting the ambient temperature Tne on the cooling side from the ambient temperature Tni on the heating box 21 side, using a protective heat box method test device 20 equipped with a heating box 21, a protective heat box 22, a cooling chamber 23, a heating means 24, an air blowing means 26, and a test piece 25. In addition, the ambient temperature Tni on the heating box 21 side and the ambient temperature Tne on the cooling side are required to be constant.

The amount of heat passing through the test specimen Φ1 is calculated by subtracting the amount of heat Φ3 passing from the peripheral wall of the heating box 21 toward the protective heat box 22 and the amount of heat loss Φ2 parallel to the surface of the test specimen 25 from the amount of heat generated Φp by the heating means 24 and the air blowing means 26 installed inside the heating box 21. "5.1 Protective heat box method" in Non-Patent Document 1 states that "Ideally, Φ2 = Φ3 = 0, but in actual measurements, it is difficult to achieve Φ2 = Φ3 = 0, and it is necessary to calibrate Φ2 and Φ3 relative to Φp." This causes the problem of the trouble of having to calibrate the amount of heat loss Φ2 and the amount of heat passing Φ3 in advance.

As shown in FIG. 5(b), the calibrated hot box test device 30 in Non-Patent Document 2 is installed at the boundary between the high temperature chamber 32 and the low temperature chamber 33, and includes a heating box 31, a heating means 34, a blowing means 35 and a baffle 36 installed inside the heating box 31, a baffle 38 and a blowing means 37 installed inside the low temperature chamber 33, and a highly insulating mounting panel 39 on which the test specimen 40 is mounted. The flow of heat flow is almost the same as that of the protected hot box test device 20 shown in FIG. 5(a), but the loss corresponding to the heat loss amount Φ2 parallel to the surface of the test specimen 40 is made almost negligible by the highly insulating mounting panel 39. Therefore, Non-Patent Document 2 also has the problem that the heat amount Φ3 passing from the peripheral wall of the heating box 31 toward the high temperature chamber 32 must be calibrated in advance using a calibration plate with a known thermal resistance, which is troublesome.

As shown in Fig. 5(a) or (b), the heat transmission coefficient measuring device 20 specified in Non-Patent Document 1 and the heat transmission coefficient measuring device 30 specified in Non-Patent Document 2 are both specified for the purpose of measuring building components, and since both basically measure flat objects, the upper edge shape of the heating box 21 or 31 is a straight shape without any irregularities. Therefore, in order to measure the heat transmission coefficient of a test object having a shape that changes in three dimensions, such as a back door of an automobile part, i.e., an insulation performance measurement object 10, it was necessary to manufacture a dedicated heating box 71 or protective heat box 72 so that the shape of the upper edge of the heating box 71 and the shape of the upper edge of the protective heat box 72 surrounding the heating box 71 match the shape of the three-dimensionally changing shape of the back door of an automobile part, as shown in Fig. 11 or 12.

For example, to measure the thermal conductivity of an automobile back door, a thermal conductivity measuring device 70 is manufactured with a shape specifically for a back door, so that the shape of the upper edge of a heating box 71, which has a heating and air blowing means 73 equipped with a heating means 3 and an air blowing means 4 inside, and the shape of the top surface of a protective thermal box 72 match the shape of a back door 74, as shown in FIG. 11, and the back door 74 is placed on the opening of the thermal conductivity measuring device 70, as shown in FIG. 12(a) or (b), and the thermal conductivity is measured with the heating box 71 closed. This means that a thermal conductivity measuring device dedicated to a specific part must be manufactured for each part with a different shape, resulting in extremely low investment efficiency and the problem of finding space to store many types of thermal conductivity measuring devices.

In addition, the heat transfer coefficient measuring device 20 specified in Non-Patent Document 1 and the heat transfer coefficient measuring device 30 specified in Non-Patent Document 2 are based on the premise that measurements are performed in a room such as a constant temperature room and that the part to be measured is brought in alone and attached to the heat transfer coefficient measuring device for measurement, which creates the troublesome problem that, for example, the back door of an automobile part must be removed from the automobile and brought in for measurement.

Furthermore, the housing of the cooling chamber of the heat transfer coefficient measuring device 20 defined in Non-Patent Document 1 or the heat transfer coefficient measuring device 30 defined in Non-Patent Document 2 is made of a light-shielding insulating material. For this reason, for example, radiant heat from natural light is generated on the exterior panel members of an automobile, but there is a problem in that it is not possible to grasp the heat transfer coefficient of the object to be measured for the heat transfer coefficient, which corresponds to the exterior panel member, due to the influence of radiant heat from natural light.

The invention in Patent Document 1 evaluates the insulation performance of the entire refrigerated vehicle body, and has the problem that it cannot measure the heat transfer coefficient, which indicates the insulation performance, for each component that makes up the vehicle.

The present invention was devised in light of these problems, and aims to provide a thermal conductivity measuring device and method that can easily measure the thermal conductivity of each part, for example an automobile with a complex shape, while it is attached to the automobile.

The heat transfer coefficient measuring device according to claim 1 is a heat transfer coefficient measuring device for measuring the amount of heat passing from one surface in contact with the high temperature side in the thickness direction of an object for measuring thermal insulation performance to the other surface in contact with the low temperature side, and is provided with a heating means and a blowing means, and includes a heating box having air-tightness and heat insulation properties, the opening of which is blocked by the installation of the object for measuring thermal insulation performance, a plurality of temperature measuring means for measuring the atmospheric temperature inside the heating box, which is the high temperature side of the object for measuring thermal insulation performance, and the atmospheric temperature of the space, which is the low temperature side of the object for measuring thermal insulation performance, and the A control unit that controls the heating means and calculates the thermal conductivity is provided, and multiple thermopiles or multiple heat flow meters are arranged at approximately equal area intervals so that the temperature difference between the inner surface and the outer surface over the entire peripheral wall of the heating box can be measured by output voltage, and a circuit is formed in which the multiple thermopiles or multiple heat flow meters are connected in series, and the control unit controls the heating means in the heating box so that the output voltage from the circuit in which the multiple thermopiles or multiple heat flow meters are connected in series becomes zero.

The heat transfer coefficient measuring device described in claim 2 is characterized in that, in claim 1, when the thickness of the peripheral wall of the heating box is approximately uniform over the entire area, multiple heat flow meters are arranged over the entire inner surface or the entire outer surface of the peripheral wall of the heating box, or multiple thermopiles are arranged over the entire inner surface and the entire outer surface of the peripheral wall of the heating box, one each at approximately equal area intervals.

The heat transfer coefficient measuring device described in claim 3 is characterized in that, in claim 1, when the thickness of the peripheral wall of the heating box is not uniform over the entire area, multiple heat flow meters are arranged at approximately equal area intervals over the entire inner surface or the entire outer surface of the peripheral wall of the heating box.

The heat transfer coefficient measuring device according to claim 4 is characterized in that, in any one of claims 1 to 3, the setting of the approximately equal area intervals is such that, when the thermopile is disposed, the entire surface on the inside and outside of the peripheral wall of the heating box is set to the same equal area intervals, or, when the heat flow meter is disposed, the entire surface on the inside or outside of the peripheral wall of the heating box is set to equal area intervals, and the approximately equal area intervals are set as intervals obtained by dividing the entire surface by any of equal area divisions from 5 equal area divisions to 80 equal area divisions.

The thermal conductivity measuring device described in claim 5 is characterized in that, in any one of claims 1 to 4, the heating box is installed within a box-shaped body so as to be detachable from the box-shaped body, and the heating box is a heating bag having a bag-like form with a peripheral wall portion that is air-tight, insulating, and flexible.

The heat transfer coefficient measuring device described in claim 6 is any one of claims 1 to 5, characterized in that the housing forming the low-temperature side space is provided with a water-cooling type cooling means that cools the air inside the housing with a heat exchanger, or an air-cooling type cooling means that blows cold air into the housing.

The heat transfer coefficient measuring device according to claim 7 is the same as in claim 6, except that the wall of the housing forming the low-temperature space facing the object to be measured for thermal insulation performance is provided with a glass wall that allows radiation from a light source provided outside the housing to the object to be measured for thermal insulation performance inside the housing.

The heat transmission coefficient measuring device described in claim 8 is the same as in claim 7, except that a plate-shaped baffle plate provided between the glass wall and the object to be measured for thermal insulation performance and approximately parallel to the object to be measured for thermal insulation performance is a glass plate that allows radiation from the light source to the object to be measured for thermal insulation performance.

The heat transfer coefficient measuring device described in claim 9 is characterized in that, in claim 7 or 8, a radiation intensity adjusting means is provided for adjusting the intensity of the radiation on the object for measuring the thermal insulation performance inside the housing.

The heat transmission coefficient measuring device described in claim 10 is any one of claims 7 to 9, characterized in that a blowing means is provided near the glass wall between the glass wall and the object to be measured for thermal insulation performance, and an airflow speed control means is provided that makes it possible to reproduce the speed of the airflow generated by the blowing means to a wind speed selected from wind speeds under natural conditions.

The heat transfer coefficient measuring method according to claim 11 is a method for measuring the heat transfer coefficient of an automobile door using a heating bag, the heating bag being provided with a heating/air blowing means disposed in the approximate center and a peripheral wall portion capable of surrounding the heating/air blowing means, the peripheral wall portion being non-breathable, heat insulating and flexible, and when the thickness of the peripheral wall portion is not uniform over the entire area, a plurality of heat flow meters are disposed one by one at intervals of approximately equal areas obtained by dividing the entire surface of the inner side or the entire surface of the outer side of the peripheral wall portion by any one of 5 equal area divisions to 80 equal area divisions, and the front The method is characterized in that it is provided with a circuit in which the plurality of heat flow meters are connected in series, the heating bag is placed inside the door opening of the vehicle, the door is closed so that the peripheral wall of the heating bag is sandwiched to block the opening, the inside of the heating bag is sealed, the heating means inside the heating bag is controlled so that the output voltage from the circuit in which the plurality of heat flow meters attached to the peripheral wall are connected in series becomes zero, the vehicle interior ambient temperature is controlled so that the vehicle interior ambient temperature is stabilized, and the thermal transmittance is calculated.

The heat transfer coefficient measuring method according to claim 12 is a method for measuring the heat transfer coefficient of an automobile door using a heating bag, the heating bag being provided with a heating/air blowing means disposed in an approximately central portion and a peripheral wall portion capable of surrounding the heating/air blowing means, the peripheral wall portion being impermeable, heat insulating and flexible, and when the thickness of the peripheral wall portion is approximately uniform over the entire area, a circuit in which a plurality of thermopiles are arranged one by one at intervals of approximately equal areas obtained by dividing each of the two sides at the same equal area division number of 5 equal area divisions to 80 equal area divisions over the entire surface of each of the two sides on the inside and outside sides of the peripheral wall portion, or a circuit in which a plurality of heat flow meters are arranged at intervals of approximately equal areas obtained by dividing each of the two sides at the same equal area division number of 5 equal area divisions to 80 equal area divisions over the entire surface of the inside side or the entire surface of the outside side of the peripheral wall portion, The heating bag is placed inside the door opening of the vehicle, the door is closed so that the peripheral wall of the heating bag is sandwiched to block the opening, and the inside of the heating bag is closed. The vehicle door is used as the object to measure the thermal insulation performance, and the heating means inside the heating bag is controlled so that the output voltage from the circuit in which the multiple thermopiles attached to the peripheral wall are connected in series or the output voltage from the circuit in which the multiple heat flow meters are connected in series becomes zero. The ambient temperature is further controlled to stabilize the ambient temperature inside the vehicle, and the thermal transmission coefficient is calculated.

The method for measuring the thermal transmittance of a vehicle according to a thirteenth aspect of the present invention is characterized in that, in the eleventh or twelfth aspect, the door is any one of a front door, a rear door, and a back door.

The heat transfer coefficient measuring device according to any one of claims 1 to 4 has the remarkable effect of making it unnecessary to know and calibrate in advance the "amount of heat loss from the peripheral wall of the heating box Φ3" specified in the protected heat box method test device of Non-Patent Document 1, since it is possible to consider the heat flow balance from the peripheral wall of the heating box to the box-shaped body as zero. This makes it possible to remove the restriction that the protected heat box, which is a constituent element of the protected heat box method test device, must be assembled integrally with the heating box, and it has become possible, for example, to substitute the protected heat box with the body of an automobile.

In addition, it has the effect of minimizing the measurement error between the thermal conductivity measured by the protected heat box method test in Non-Patent Document 1 and the thermal conductivity measured by the thermal conductivity measuring device of the present invention.

The heat transfer coefficient measuring device described in claim 5 has the advantage that, in the past, when measuring an object whose shape changes in three dimensions, a protective heat box and a heating box had to be made from materials that are impermeable and insulating to match the outer shape of the object whose shape changes in three dimensions, and only that object could be used for the object. However, by making the material of the peripheral wall of the heating box a flexible member, one heating bag can be used for objects whose shapes change in three dimensions, and one heating bag can be used for objects whose shapes change in three dimensions.

The heat transfer coefficient measuring device described in claim 6 has an effect that, since the cooling means can be easily carried around, it is possible to obtain a highly accurate heat transfer coefficient regardless of the measurement location, whether inside or outside a room, without having to measure in a low-temperature constant temperature room or using a cooling chamber integrated with the heating box as specified in Non-Patent Document 1 or Non-Patent Document 2.

The heat transfer coefficient measuring device described in claims 7 to 9 has the effect of being able to measure the heat transfer coefficient when it is affected by radiant heat generated from natural light such as the sun, which occurs, for example, on the exterior panel components of an automobile.

The heat transfer coefficient measuring device described in claim 10 has the effect of being able to measure the heat transfer coefficient when it is affected by wind speed, which is a natural condition.

The method for measuring the heat transfer coefficient of an automobile door described in any one of claims 11 to 13 has the effect of being able to measure the heat transfer coefficient by attaching a heating bag with the door attached to the automobile.

FIG. 1 is an explanatory diagram of a thermal conductivity measuring device of the present invention, in which the material of the peripheral wall of the heating box is a flexible material, (a) is an explanatory diagram of a plan view when expanded with thermopiles arranged at equal area intervals, and (b) is an explanatory diagram of the A-A cross section of (a). 1A is an explanatory diagram showing a plurality of thermopiles arranged over the entire peripheral wall of a heating box of a thermal conductivity measuring device of the present invention, and FIG. 1B is an explanatory diagram showing a plurality of heat flow meters arranged over the entire peripheral wall of a heating box of the present invention. FIG. 1A is an explanatory diagram showing a thermopile arranged over the entire area of the peripheral wall portion made of a flexible material of the heating box of the thermal conductivity measuring device of the present invention, and FIG. 1B is an explanatory diagram showing a plurality of heat flow meters arranged over the entire area of the peripheral wall portion made of a flexible material of the heating box of the thermal conductivity measuring device of the present invention. 1A and 1B are explanatory diagrams of a portable cooling box provided on the low-temperature side, in which FIG. 1A is an explanatory diagram of a water-cooling system, and FIG. 1B is an explanatory diagram of an air-cooling system. FIG. 1 is an explanatory diagram of Japanese Industrial Standards, in which (a) is an explanatory diagram of a protected hot box test device of Japanese Industrial Standards JIS A1420 in Non-Patent Document 1, and (b) is an explanatory diagram of a calibrated hot box test device of Japanese Industrial Standards JIS A4710 in Non-Patent Document 2. 1 is an explanatory diagram of an apparatus for testing the placement interval and measurement error of thermopiles and the like placed in a heating box. FIG. FIG. 7 shows an exploded view of the heating box and an explanatory diagram of equal area spacing; (a) is an explanatory diagram of 1 equal area spacing on one side and 5 equal area spacing across the entire surface; (b) is an explanatory diagram of 4 equal area spacing on one side and 20 equal area spacing across the entire surface; and (c) is an explanatory diagram of 9 equal area spacing on one side and 45 equal area spacing across the entire surface. 11 is a diagram showing the relationship between the number of equal area divisions for the entire surface of the wall portion, which determines the spacing between the thermopiles, and the thermopile measurement error. FIG. FIG. 1 is a diagram showing test results of the reliability of the measured values of the thermal conductivity measuring device of the present invention using a test specimen with known thermal conductivity. This is an explanatory diagram of the parts of an automobile that are to be measured for their thermal transmittance, showing parts to which a heating bag can be attached and parts to which a heating bag cannot be attached unless the parts are removed from the automobile. 1 is an explanatory diagram of a heating box whose upper edge is manufactured to fit the outer peripheral shape of, for example, a back door. 12A and 12B are diagrams showing a back door attached to the heating box shown in FIG. 11, in which (a) is a perspective explanatory diagram showing the back door attached, and (b) is a cross-sectional explanatory diagram taken along the line BB of (a). FIG. 1 shows a heating bag of the thermal conductivity measuring device of the present invention attached to the back door of an automobile, where (a) is an explanatory diagram of the state of the heating bag attached to the back door as viewed from inside the vehicle, and (b) is an explanatory diagram of the state of the heating bag attached with the back door open as viewed from outside the vehicle. This is an exploded view of the heating box and an explanatory diagram of equal area intervals, showing 36 equal area intervals over the entire surface when one surface is the entire surface. FIG. 1 is an explanatory diagram of a heat transfer coefficient measuring device to which a light source and a glass wall portion, etc. are additionally installed. 1 is a diagram showing the relationship between the air volume of a blower and the coefficient of overall heat transmission in the presence of radiant heat. FIG. 13 is a graph showing the change in thermal transmittance when there is no radiant heat and when there is radiant heat due to light irradiation.

The heat transfer coefficient measuring device 1 and method of the present invention are a device and method for measuring the heat transfer coefficient of an object 10 for thermal insulation performance measurement. The inventors came up with the heat transfer coefficient measuring device 1 and method of the present invention to solve the problems of Non-Patent Document 1 and Non-Patent Document 2, namely, the troublesome problem of having to calibrate the amount of heat Φ3 passing from the peripheral wall of the heating box 2 toward the protective thermal box 6 in advance using a calibration plate with a known thermal resistance, and the problem of having to manufacture dedicated heating boxes 2 and protective thermal boxes 6 so that the shapes of the upper edges of the heating box 2 and protective thermal box 6 that receive the object 10 for thermal insulation performance measurement are matched to the three-dimensionally changing shape of the object 10 for thermal insulation performance measurement.

As shown in FIG. 2(a) or FIG. 2(b), the heat transfer coefficient measuring device 1 of the present invention is a heat transfer coefficient measuring device 1 that measures the amount of heat passing from one surface in contact with the high temperature side in the thickness direction of the insulation performance measurement object 10 to the other surface in contact with the low temperature side, and is provided with a heating means 3 and an air blowing means 4, and a heating box 2 that has no air permeability and is insulated and whose opening is blocked by the installation of the insulation performance measurement object 10, and a complex device that measures the atmospheric temperature inside the heating box 2 that is the high temperature side of the insulation performance measurement object 10 and the atmospheric temperature of the space that is the low temperature side of the insulation performance measurement object 10, respectively. The heating box 2 is provided with a number of temperature measuring means 15, 16, and a control unit 7 that controls the heating means 3 and calculates the thermal conductivity. A number of thermopiles 11 or a number of heat flow meters 12 are arranged at approximately equal area intervals so that the temperature difference between the inner surface and the outer surface over the entire area of the peripheral wall portion 9 of the heating box 2 can be measured by output voltage. A circuit is formed in which the number of thermopiles 11 or the number of heat flow meters 12 are connected in series, and the control unit 7 controls the heating means 3 in the heating box 2 so that the output voltage from the circuit in which the number of thermopiles 11 or the number of heat flow meters 12 are connected in series becomes zero.

The heat transfer coefficient measuring device 1 also includes a box-shaped body 6 that surrounds the entire peripheral wall portion 9 of the heating box 2 and forms a closed space together with the heating box 2. A heating means 19 and an air blowing means 17 are provided within the box-shaped body 6. The air blowing means 17 continues to operate, and the control unit 7 controls the heating means 19 based on temperature information from a temperature measuring means (not shown) provided within the box-shaped body 6 so as to keep the atmospheric temperature within the box-shaped body 6 constant.

The heat transfer coefficient measuring device 1 can be of type A, in which the heating box 2a and the box-shaped body 6 are separate, as shown in FIG. 1, or type B, in which the heating box 2 and the box-shaped body 6 are assembled together, as shown in FIG. 2 or 3. In the case of type A, the box-shaped body 6 corresponds to, for example, the body of an automobile 80 that forms the interior of the vehicle in which the passengers sit.

In other words, in the case of the form A, the housing of the box-shaped body 6 of the heat transfer coefficient measuring device 1 can be substituted with the body of the automobile 80, and by bringing the heating means 19, the air blowing means 17, the interior temperature stabilization means including the interior ambient temperature measuring means and the control means into the interior of the automobile 80, the device can perform the same functions as the box-shaped body 6.

As shown in FIG. 2 or 3, the heat transmission coefficient measuring device 1 supports the insulation performance measurement object 10 only on the insulating peripheral wall 9 of the heating box 2 and is isolated from the box-shaped body 6, so the heat loss parallel to the surface of the insulation performance measurement object 10 can be considered to be zero, and the output voltage representing the temperature difference between the inner surface and the outer surface over the entire area of the peripheral wall 9 of the heating box 2 is controlled to zero, so the heat flow balance from the peripheral wall 9 of the heating box 2 to the box-shaped body 6 can be considered to be zero. This has eliminated the first problem, which was the inconvenience of having to calibrate the heat amount Φ3 passing from the peripheral wall of the heating box 2 toward the protective heat box 6 and the heat loss amount Φ2 parallel to the test object surface in advance using a calibration plate with a known thermal resistance.

Therefore, the heat transfer coefficient measuring device 1 can calculate the heat transfer coefficient of the insulation performance measurement object 10 using the amount of heat passing through the insulation performance measurement object 10 from the inside of the heating box 2 to the space on the low temperature side along the thickness direction of the insulation performance measurement object 10, which is calculated from the measured values of the power consumed in the heating means 3 and the air blowing means 4, the area perpendicular to the heat flow in the insulation performance measurement object 10, the atmospheric temperature inside the heating box 2, and the atmospheric temperature of the space on the low temperature side of the insulation performance measurement object 10. Therefore, by using the heat transfer coefficient measuring device 1, if the amount of heat supplied to the heating box Φp calculated from the measured values of the power consumed in the heating means 3 and the air blowing means 4 is grasped, the heat transfer coefficient of the insulation performance measurement object 10 can be easily calculated without considering the heat transfer coefficient Φ3 and the heat loss coefficient Φ2.

As shown in FIG. 2, the heating box 2 of the heat transfer coefficient measuring device 1 of the present invention has a heating means 3 and an air blowing means 4 installed therein, and the opening is blocked by attaching the insulation performance measurement object 10 to the heating box 2. The peripheral wall 9 of the heating box 2 is impermeable and insulating, and the temperature inside the heating box 2 is maintained constant. The heating means 3 may be any device capable of heating, such as a heater, and the air blowing means 4 may be any device capable of blowing air, such as a fan. The heating means 3 is controlled by the control unit 7, but the air blowing means 4 is operated constantly without being controlled by the control unit 7.

As shown in Figures 2 and 3, the heating box 2 is a housing with an opening at the top, and the object 10 to be measured for thermal insulation performance is placed on the periphery of the upper opening, and the object 10 to be measured for thermal insulation performance is isolated from the box-shaped body 6 so that it does not come into contact with the box-shaped body 6. The peripheral wall 9 of the heating box 2 is made of a material that is at least breathable and insulating. The heating box 2 is equipped with a heating means 3, a blowing means 4, and a temperature measuring means 15.

By supporting the object 10 to be measured for thermal insulation performance only at the peripheral portion 9 of the heating box 2 and making contact only with the peripheral portion 9, the amount of heat loss on the side of the object 10 to be measured for thermal insulation performance can be considered to be zero.

The plurality of temperature measuring means 15, 16 at least include a temperature sensor 15 for measuring the atmospheric temperature inside the heating box 2, which is the high temperature side of the insulation performance measurement object 10, and a temperature sensor 16 for measuring the atmospheric temperature of the space, which is the low temperature side of the insulation performance measurement object 10. The temperature information from the temperature sensors 15, 16 is stored in a data logger (not shown) installed in the control unit 7. The atmospheric temperature inside the heating box 2 and the atmospheric temperature of the space, which is the low temperature side, are calculated by the control unit 7 as data for calculating the overall heat transfer coefficient.

Next, the control unit 7 controls the heating means 3 installed inside the heating box 2 so that the output voltage from the circuit in which the plurality of thermopiles 11 are connected in series or the output voltage from the circuit in which the plurality of heat flow meters 12 are connected in series becomes zero, inputs the atmospheric temperature inside the heating box 2 from the temperature sensor 15 and the atmospheric temperature of the space on the low-temperature side of the insulation performance measurement object 10 from the temperature sensor 16 into a data logger (not shown) for storage, and performs control to derive and output the thermal conductivity based on the previously known heat transfer area of the insulation performance measurement object 10 (area perpendicular to the heat flow in the insulation performance measurement object 10) and the amount of heat supplied by the heating means 3 and the air blowing means 4. The output can be displayed on a display provided in the control unit 7 or on the screen of a connected personal computer.

The box-shaped body 6 surrounds the entire peripheral wall portion 9 of the heating box 2 and forms a closed space with the heating box 2. The present invention is an improvement of the protective heat box 22 in Non-Patent Document 1 and the high-temperature chamber 32 in Non-Patent Document 2, and the present invention is sufficient as long as it can form a closed space with the heating box 2, and it can be the interior of a car instead of a protective heat box or high-temperature chamber. For example, as shown in Figure 10, the heating box 2 can be installed in the interior 81 of a car 80 with all doors closed to enable measurement. The box-shaped body 6 corresponds to the body of the car 80, and the closed space between the heating box 2 and the box-shaped body 6 corresponds to the interior of the car 80 with all doors closed.

Next, the thermopile 11 or heat flow meter 12 will be described. When the thickness of the peripheral wall 9 of the heating box 2 is approximately uniform over the entire area, a plurality of heat flow meters 12 are disposed over the entire inner surface or the entire outer surface of the peripheral wall 9 of the heating box 2, or a plurality of thermopiles 11 are disposed over the entire inner surface and the entire outer surface of the peripheral wall 9 of the heating box 2, at approximately equal area intervals, as shown in Figures 1(a), (b), 2(a), (b), or 3(a), (b).

Also, as shown in FIG. 2(b) or FIG. 3(b), if the thickness of the peripheral wall portion 9 of the heating box 2 is not uniform over the entire area, multiple heat flow meters 12 are arranged at approximately equal area intervals over the entire inner surface or the entire outer surface of the peripheral wall portion 9 of the heating box 2.

When the output voltage from the circuit in which the plurality of thermopiles 11 are connected in series or the output voltage from the circuit in which the plurality of heat flow meters 12 are connected in series becomes zero, the heat flow balance through the peripheral wall 9 of the heating box 2 to the space formed by the box-shaped body 6 can be considered to be in a zero state. This makes it unnecessary to carry out the troublesome task of determining and calibrating in advance the "amount of heat loss from the peripheral wall of the heating box Φ3" defined in the Protective Heat Box Method of Non-Patent Document 1 as shown in Figure 5(a).

Next, it was verified using a heat transfer coefficient measuring device 1c for thermopile arrangement study as shown in Figure 6 that a high-precision heat transfer coefficient can be obtained by arranging multiple thermopiles 11 at approximately equal area intervals on the entire inner surface and the entire outer surface of the peripheral wall 9 and controlling the output voltage from the multiple thermopiles 11 to zero. The heat transfer coefficient measuring device 1c is equipped with the peripheral wall 9 of the heating box 2 and the box-shaped body 6, and all five sides of the peripheral wall 9 are 1 m square. Since the thermal conductivity and thickness of the peripheral wall 9 of the heating box 2 are known, the amount of heat Q2 passing through the peripheral wall 9 can be calculated. In addition, since the heat transfer coefficient, heat transfer area, heating box interior ambient temperature, and cooling side ambient temperature of the test specimen 10a can be grasped, the amount of heat Q1 passing through the test specimen 10a can be obtained. Therefore, the measurement error is calculated by dividing the amount of heat Q1 passing through the test piece 10a by the amount of heat Q2 passing through the peripheral wall 9 of the heating box 2 minus the total heat flow balance value Q3 measured by the thermopile 11 or heat flow meter 12, which is the numerator.

That is, the calculated amount of heat passed Q2 was compared with the amount of heat passed Q3 measured by the thermopile 11 or the heat flow meter 12. If the difference between the amount of heat passed Q2 and the total heat flow balance value Q3 is large, the measurement error increases, and if the difference between the amount of heat passed Q2 and the total heat flow balance value Q3 is small, the measurement error decreases.

Test example 1 is a case where one thermopile is placed at the center of one 1 m square surface as shown in Figure 7 (a), which is a development of the peripheral wall portion 9, and the entire surface is divided into five equal areas, and the thermopiles placed on the five surfaces are connected in series to form a plurality of thermopiles 11 consisting of five thermopiles. Test example 2 is a case where one 1 m square surface is divided into four equal areas as shown in Figure 7 (b), which is a development of the peripheral wall portion 9, and the entire surface is divided into 20 equal areas, and the thermopiles placed on the five surfaces are connected in series to form a plurality of thermopiles 11 consisting of 20 thermopiles. Test example 3 is a case in which one side of 1 m square is divided into 9 equal areas, with one thermopile placed at the center of each, resulting in 45 equal areas across the entire surface, as shown in Figure 7 (c), which is a development of the peripheral wall portion 9, and the thermopiles placed on five sides are connected in series to form a plurality of thermopiles 11 consisting of 45 thermopiles.

Although not tested as a test example, the same equal area intervals as in the case of the thermopile 11 can be applied even if the thermopile 11 is replaced with a heat flow meter 12. Also, the peripheral wall 9 is not limited to having five faces as shown in FIG. 7, and may have a single face as the entire peripheral wall 9 as shown in FIG. 14. When the peripheral wall 9 has a single face as shown in FIG. 14, for example, 36 equal area divisions can be made, and multiple thermopiles 11 or multiple heat flow meters 12 can be arranged at equal area intervals. In other words, by changing the number of vertical and horizontal divisions, it is possible to arbitrarily set the number of equal area divisions to, for example, 80, 70, 60, 50, etc.

In addition, the measurement error due to the number of equal area divisions was verified by changing the thermal conductivity of the test specimen 10a to 1 W/ ^m2K (symbol △ in FIG. 8), 2 W/ ^m2K (symbol □ in FIG. 8), and 4 W/ ^m2K (symbol ◯ in FIG. 8), and the results are shown in FIG. 8. In FIG. 8, division symbol L indicates the case of 45 equal area divisions, division symbol M indicates the case of 20 equal area divisions, and division symbol N indicates the case of 5 equal area divisions. When there was no equal area division and only one thermopile 11 was provided on the entire surface, the measurement error was 79.3% when the thermal conductivity was 1 W/ ^m2K , the measurement error was 39.6% when the thermal conductivity was 2 W/ ^m2K , and the ^measurement error was 19.8% when the thermal conductivity was 4 W/m2K.

FIG. 8 shows that the measurement error is smaller when the number of equal area divisions is 20 (equal area of 0.25 ^m2 ) than when the number of equal area divisions is 5, and further when the number of equal area divisions is 45 (equal area of 0.11 ^m2 ), that is, when the number of equal area divisions increases. It is also shown that the measurement error is smaller for a member with a higher thermal transmittance of the test piece 10a. Thus, in order to reduce the measurement error, the equal area interval at which the thermopile 11 is disposed is preferably 20 or more, more preferably 45 or more, and even more preferably 80. Note that, when five 1 m square surfaces are combined to form five surfaces as shown in FIG. 7(a), the equal area is preferably 0.25 ^m2 or less, and more preferably 0.11 ^m2 or less.

Therefore, when the thermopile 11 is disposed, the entire surface of the inner and outer sides of the peripheral wall portion 9 of the heating box 2 is set to have the same equal area intervals, or when the heat flow meter 12 is disposed, the entire surface of the inner or outer side of the peripheral wall portion 9 of the heating box 2 is set to have equal area intervals, and the equal area intervals are set to approximately equal areas obtained by dividing the entire surface into equal area divisions of any number between 5 equal area divisions and 80 equal area divisions.

If the equal area division is less than 5, the measurement error will be too large and problematic, and if the equal area division is more than 80, the measurement error will be minimal, but there is a problem that it takes a lot of time to install the thermopile 11 or heat flow meter 12 and is expensive, so it is preferable that the equal area interval be any number between 5 and 80 equal area divisions.

Next, the influence of the temperature difference between the outside air temperature measured by the temperature sensor 16 (corresponding to the air temperature of the cooling chamber 23 of the protective heat box method test device 20 shown in FIG. 5(a), the air temperature of the low temperature room 33 of the calibrated heat box method test device 30 shown in FIG. 5(b), and the air temperature of the space on the low temperature side of the thermal insulation performance measurement object 10 of the present invention) and the temperature of the atmosphere inside the heating box 2 measured by the temperature sensor 15 on the thermal transmission coefficient measurement was tested using the thermal insulation performance measurement object 10, which uses a known building insulation material with a thermal conductivity of 0.02 W/mK, and the control unit 7 controlled the output voltage from the circuit in which the thermopiles 11 arranged at approximately equal intervals with a division area of approximately 0.11 ^m2 were connected in series to zero. The temperature difference between the outside air temperature and the atmospheric temperature inside the heating box is shown in graph Q for a temperature difference of 10° C., graph R for a temperature difference of 20° C., and graph S for a temperature difference of 30° C., and the results are shown in FIG. 9. Since the object 10 for measuring the heat insulation performance is a flat plate having a uniform thickness, the heat transmission coefficient is converted into thermal conductivity and shown in FIG.

As can be seen from Figure 9, when the temperature difference is 20°C or more, a value close to the thermal conductivity of the building insulation material used in the test, 0.02 W/mK, is obtained. Therefore, it is preferable to measure the thermal conductivity by setting the temperature difference between the ambient temperature in the heating box 2 and the air temperature in the space on the low-temperature side of the insulation performance measurement object 10 to 20°C or more.

Next, as shown in FIG. 3, the heating box 2 can be installed so as to be removable from the box-shaped body 6, and the heating box 2 can be a heating bag 2a having a bag-like shape with a peripheral wall portion 9a that is non-breathable, heat-insulating, and flexible. When the heating bag 2a is removed from the box-shaped body 6, the heat transmission coefficient measuring device 1a has a shape as shown in FIGS. 1(a) and (b).

That is, the peripheral wall 9a of the heating bag 2a of the heat transmission coefficient measuring device 1 as shown in FIG. 3 is made of a flexible material, such as a foam sealing material or rubber material that is impermeable, insulating, and flexible, such as a 20 mm thick EPT SEALER (manufactured by Nitto Denko Corporation). The thickness of the peripheral wall 9a is at least 10 mm, preferably 20 mm or more, taking into consideration the possibility of mounting the thermopile 11 or heat flow meter 12 and insulating properties.

When the peripheral wall portion 9a of the heating bag 2a is made of a material that is impermeable, insulating, and flexible, it can be spread out flat as shown in Fig. 1(a) in a plan view or Fig. 1(b) in a side view, and the heating means 3 and the air blowing means 4 are installed inside, and the heating and air blowing means 8 (with the heating means 3 and the air blowing means 4 installed inside) with an opening 8a on the upper surface side is arranged in the center, and the thermopile 11 or heat flow meter 12 is arranged in series at equal area intervals on the airless, insulating, and flexible material. Since it becomes a flexible bag-like body, it can be spread out flat or folded and changed into a wrapped bag-like body.

The peripheral wall 9a of the heating bag 2a is a material that is impermeable, insulating, and flexible, and can be used as a bag-shaped body, so it can be used as a bag-shaped body equipped with a thermopile 11 as shown in FIG. 3(a), or as a bag-shaped body equipped with a heat flow meter 12 as shown in FIG. 3(b). By making the peripheral wall 9a bag-shaped and flexible, the degree of freedom of the attachment part to the insulation performance measurement object 10 is increased, and the insulation performance of the insulation performance measurement object 10, which has a shape that changes in three dimensions, and has multiple different shapes, can be measured with a single heat transfer coefficient measuring device 1a equipped with a heating bag 2a. This has solved the second problem, which was that "the shape of the upper edge of each of the heating box 2 and the protective heat box 6 that receive the insulation performance measurement object 10 must be made to match the shape of the insulation performance measurement object 10 that changes in three dimensions."

For example, as shown in FIG. 10, the heat transfer coefficient of an openable door such as a front door 83 of an automobile 80 can be measured while it is attached to the automobile 80, and as shown in FIG. 13(b), a heat transfer coefficient measuring device 1a equipped with a heating/blowing means 8 and a flexible peripheral wall portion 9a is set at the opening of a back door 74, and the heat transfer coefficient can be measured with the back door 74 closed so that the peripheral portion of the peripheral wall portion 9a is clamped to the edge of the opening of the back door 74 as shown in FIG. 13(a).

For example, as shown in FIG. 10, the windshield 82 cannot be opened or closed, so it is removed from the automobile 80. However, it is not necessary to manufacture a new heating box 2 with a peripheral wall portion of a special shape that matches the three-dimensional shape of the windshield 82, and the thermal conductivity can be measured using a flexible heating bag 2a.

Next, as shown in FIG. 4, the housing 18 forming the low-temperature space is provided with a water-cooled cooling means 50 that cools the air inside the housing 18 using a heat exchanger 43, or an air-cooled cooling means 50 that blows cold air into the housing 18.

The space within the housing 18 corresponds to the space that is the low-temperature side of the insulation performance measurement object 10 of the present invention, and is an improvement of the cooling chamber 23 of the protective heat box method test device 20 shown in FIG. 5(a), or an improvement of the low-temperature room 33 of the calibrated heat box method test device 30 shown in FIG. 5(b). The protective heat box method test device 20 and the calibrated heat box method test device 30 are also intended to measure large building materials, and therefore are premised on measurements in a room such as a thermostatic room, so the cooling chamber 23 or the low-temperature room 33 is large and cannot be easily carried. Since the heat transmission coefficient measurement device 1 or 1a of the present invention can be made portable, a portable cooling means 50 was conceived accordingly.

As shown in FIG. 4(a), the water-cooled cooling means 50 is configured such that cold water cooled by a circulating water cooling device 41 flows through a pipe 42 and cools the air inside the housing 18 in a heat exchanger 43 provided inside the housing 18, and the cooled air G flows in a laminar flow toward the object 10 to be measured for thermal insulation performance by the air blowing means 45, guided by a baffle 44. It is preferable to maintain a difference of 20°C or more between the ambient temperature inside the heating box 6 and the temperature of the cooled air G.

As shown in FIG. 4(b), the air-cooled cooling means 50 causes the cooling air G cooled by the circulating air cooling device 41a to flow in a laminar flow through the duct 46 and toward the object 10 for thermal insulation performance measurement while being guided by a partition plate 47 provided in the housing 18. It is preferable to have a difference of 20°C or more between the ambient temperature in the heating box 2 and the temperature of the cooling air G.

The portable cooling means 50 eliminates limitations on the location where the thermal conductivity can be measured, such as the low-temperature chamber 33 specified in the calibrated heat box method test device 30, and does not require a large-scale constant temperature chamber, so it is easy to achieve a difference of 20°C or more between the ambient temperature in the heating box 2 and the temperature of the cooling air G at the location where the insulation performance measurement object 10 is attached, thereby improving the accuracy of the measurement at the location where the insulation performance measurement object 10 is attached.

Next, we will explain the heat transmission coefficient measuring device 1b, which can measure the heat transmission coefficient when the low-temperature side is affected by natural conditions such as radiation from the sun and wind speed. As shown in Figure 15, the heat transmission coefficient measuring device 1b has a glass wall 61 on the wall of the housing 18 that forms the space on the low-temperature side, facing the object 10 to be measured for thermal insulation performance, which allows radiation from a light source 60 provided outside the housing 18 to the object 10 to be measured for thermal insulation performance inside the housing 18.

When a baffle plate 44a is installed to obtain a uniform air temperature distribution within the housing 18, the plate-shaped baffle plate 44a is provided between the glass wall portion 61 and the object 10 for measuring thermal insulation performance, approximately parallel to the object 10 for measuring thermal insulation performance, and is a glass plate that allows radiation from the light source 60 to the object 10 for measuring thermal insulation performance.

A radiation intensity adjustment means is provided to enable measurement of the thermal transmission coefficient when, for example, the exterior panel of an automobile is affected by radiation from the sun, which is a natural condition. The radiation intensity adjustment means is, for example, a means for controlling the light source temperature to be higher when increasing the radiation intensity, i.e., when increasing the radiant heat, and for controlling the light source temperature to be lowered when decreasing the radiation intensity, i.e., when decreasing the radiant heat. The radiation intensity adjustment means is, for example, a slidac that controls the temperature of the light source 60 and is provided in the control unit 7, which converts the magnitude of the voltage applied to the light source 60. By adjusting the radiation intensity adjustment means, the radiation intensity for the insulation performance measurement object 10 in the housing 18 is adjusted.

Furthermore, in order to be able to measure the thermal transmission coefficient when, for example, the outer panel of an automobile is affected by wind, which is a natural condition, a blowing means 45 is provided between the glass wall portion 61 and the object 10 for measuring thermal insulation performance, near the glass wall portion 61, and an airflow speed control means is provided in the control unit 7 to be able to reproduce a wind speed selected from wind speeds under natural conditions, and the speed of the airflow generated by the blowing means 45 is adjusted.

First, the relationship between the air volume of the blower 45 and the thermal conductivity obtained using the thermal conductivity measuring device 1b will be described. As shown in FIG. 16, flat aluminum plates (thickness 3 mm, △ mark), polypropylene plates (thickness 0.7 mm, □ mark), and glass plates (thickness 4 mm, ◯ mark) were used as the insulation performance measurement objects 10. The horizontal axis shows the air volume, and the vertical axis shows the thermal conductivity. In order to reproduce natural conditions and verify the effect of radiation from sunlight, the light source 60 was turned on to monitor the radiant heat of the radiation sensor 63, and the radiation intensity of the light source 60 was adjusted.

Figure 16 shows that the higher the air volume, i.e., the faster the airflow speed, the more gradually the heat transfer coefficient increases regardless of the material of the insulation performance measurement object 10. This shows that when there is wind under natural conditions, for example, the flow of heat from the interior of the automobile through the exterior panel of the automobile increases as the air volume increases. Therefore, the heat transfer coefficient measuring device 1b of the invention can be used to evaluate the insulation performance of an automobile door structure taking into account the effects of wind.

Next, the relationship between the radiation and the thermal conductivity obtained by irradiating light to reproduce sunlight, obtained using the thermal conductivity measuring device 1b, will be explained. As shown in FIG. 17, in order to verify the effect of radiation close to natural conditions, the light source 60 was turned on to create a daytime period with radiation close to natural conditions, and the light source 60 was turned off to create a nighttime period with no radiation. As the objects 10 to be measured for the thermal insulation performance, flat plates of an aluminum plate (thickness 3 mm, △ mark), a polypropylene plate (thickness 0.7 mm, □ mark), and a glass plate (thickness 4 mm, ◯ mark) were used. The horizontal axis shows the elapsed time, and the vertical axis shows the thermal conductivity.

As shown in FIG. 17, when no radiant heat is generated by the light source 60, the thermal conductivity of the insulation performance measurement object 10 is approximately the same for all materials, but when radiant heat is generated by the light source 60, the thermal conductivity of the insulation performance measurement object 10 varies depending on the material. For example, in the case of an aluminum plate (△ mark), the thermal conductivity is approximately constant whether or not radiant heat is generated by the light source 60, whereas in the case of a polypropylene plate (□ mark) or a glass plate (◯ mark), the apparent thermal conductivity is lower when radiant heat is generated by the light source 60 compared to when it is not generated. This shows that the thermal insulation performance against radiant heat is poorer for polypropylene plates and glass plates than for aluminum plates.

Next, the method of measuring the thermal conductivity will be described. When the thickness of the peripheral wall portion 9a is not uniform over the entire area, the first method of measuring the thermal conductivity is a method of measuring the thermal conductivity of the door of an automobile 80 using a heating bag 2a as shown in Figures 1 and 13, in which the heating bag 2a is provided with a heating/air blowing means 8 arranged in the approximate center and a peripheral wall portion 9a capable of surrounding the heating/air blowing means 8, the peripheral wall portion 9a being non-breathable, heat insulating and flexible, and a plurality of heat flow meters 12 are arranged one by one at intervals of approximately equal areas obtained by dividing the entire surface of the inner side or the entire surface of the outer side of the peripheral wall portion 9a by any one of 5 equal area divisions to 80 equal area divisions. The method includes a circuit in which the plurality of heat flow meters 12 are connected in series, the heating bag 2a is placed inside the door opening of the automobile 80, the door is closed so that the peripheral wall portion 9a of the heating bag 2a is sandwiched to block the opening, and the inside of the heating bag 2a is closed. The door of the automobile 80 is used as the insulation performance measurement object 10, and the heating means 3 inside the heating bag 2a is controlled so that the output voltage from the circuit in which the plurality of heat flow meters 12 attached to the peripheral wall portion 9a are connected in series becomes zero. Furthermore, the interior atmosphere temperature of the automobile 80 is controlled so that the interior atmosphere temperature is stabilized, and the heat transfer coefficient is calculated.

In addition, when the thickness of the peripheral wall portion 9a is approximately uniform over the entire area, the second method of measuring the thermal transmission coefficient is a method of measuring the thermal transmission coefficient of a door of an automobile 80 using a heating bag 2a, the heating bag 2a is provided with a heating/air blowing means 8 arranged in approximately the center and a peripheral wall portion 9a capable of surrounding the heating/air blowing means 8, the peripheral wall portion 9a being non-breathable, heat insulating and flexible, and a circuit in which a plurality of thermopiles 11 are arranged one by one over the entire surface of each of the two inner and outer sides of the peripheral wall portion 9a at intervals of approximately equal areas obtained by dividing each of the two sides by any of the same equal area division numbers of 5 equal area divisions to 80 equal area divisions, and the plurality of thermopiles 11 are connected in series, or a circuit in which a plurality of heat flow meters 12 are arranged over the entire surface of the inner side or the entire surface of the outer side of the peripheral wall portion 9a at intervals of approximately equal areas obtained by dividing each of the two sides by any of the same equal area division numbers of 5 equal area divisions to 80 equal area divisions, The method includes a circuit in which the plurality of thermopiles 11 are connected in series, arranged one by one at intervals of approximately equal areas obtained by dividing the plurality of thermopiles 11 into any of the 80 equal area divisions, placing the heating bag 2a inside the door opening of the automobile 80, closing the door so that the peripheral wall portion 9a of the heating bag 2a is sandwiched to block the opening, and closing the inside of the heating bag 2a, and controlling the heating means 3 in the heating bag 2a so that the output voltage from the circuit in which the plurality of thermopiles 11 attached to the peripheral wall portion 9a are connected in series or the output voltage from the circuit in which the plurality of heat flow meters 12 are connected in series becomes zero, and further controlling the ambient temperature so as to stabilize the ambient temperature inside the automobile 80, thereby calculating the thermal transmission coefficient.

In both the first and second methods of measuring the thermal transmittance, the temperature of the enclosed space inside the automobile 80 is measured by bringing the automobile 80 indoors to avoid the effects of outdoor sunlight, bringing an interior temperature stabilization means (not shown) equipped with a heating means (not shown) and an air blowing means (not shown) into the vehicle, operating the brought-in air blowing means at all times during the measurement, and controlling the operation of the brought-in heating means so as to stabilize the interior ambient temperature, thereby stabilizing and keeping the interior ambient temperature approximately constant.

The vehicle interior temperature stabilization means that is brought into the vehicle interior 80 is equipped with a heating means, an air blowing means, a vehicle interior ambient temperature measuring means, and a control means that controls the operation of the heating means based on temperature information from the vehicle interior ambient temperature measuring means.

The door is preferably a door that can be closed by pinching the peripheral wall portion 9a of the heating bag 2a, and may be a front door, rear door, or back door.

Next, an example of using the heat transfer coefficient measuring device 1 to measure the heat transfer coefficient when the back door 74 is attached to the automobile 80 as shown in Figure 13 will be described. First, as shown in Figure 1, a heat transfer coefficient measuring device 1a is prepared, which includes a bag-shaped heating bag 2a with a peripheral wall 9a that is impermeable, insulating, and flexible, a heating and air blowing means 8 with a heating means 3 and an air blowing means 4 disposed approximately in the center of the heating bag 2a, a temperature measuring means 15 for measuring the atmospheric temperature inside the heating bag 2a, a temperature measuring means 16 for measuring the external atmospheric temperature, and a control unit 7.

Since the thickness of the peripheral wall portion 9a is approximately the same over the entire area, multiple thermopiles were used, arranged one by one over the entire inner surface and the entire outer surface of the peripheral wall portion 9a of the heating box 2a at approximately equal area intervals obtained by dividing the entire surface into 45 equal area divisions.

Next, the automobile 80 is moved indoors to avoid being affected by sunlight. Then, as shown in FIG. 13(b), the back door 74 is opened and the flexible peripheral wall portion 9a is expanded to cover the opening of the back door 74 so that the heating/blowing means 8 is on the back door 74 side, and the back door 74 is closed while maintaining this state. As a result, a closed space is formed inside the heating bag 2a as shown in FIG. 13(a).

Then, an in-vehicle temperature stabilization means (not shown) equipped with a heating means (not shown) and an air blowing means (not shown) is brought into the vehicle, the seatbacks are reclined and the in-vehicle temperature stabilization means is placed on top of the seatbacks, and all doors are closed. By closing all the doors inside the vehicle, an enclosed space is also formed. This enclosed space corresponds to the enclosed space of the protective thermal box. The air blowing means is then operated, and the operation of the heating means is controlled based on the in-vehicle ambient temperature information to stabilize the ambient temperature inside the vehicle.

Then, the blowing means 4 of the heating and blowing means 8 installed in the heating bag 2a is operated, and the heating means 3 in the heating bag 2a is controlled so that the output voltage from the circuit in which the multiple thermopiles are connected in series becomes zero.

The control unit 7 then calculates the thermal conductivity of the back door 74 using the ambient temperature inside the heating bag 2a, which is the high-temperature side of the back door 74, the ambient temperature of the space outside the vehicle, which is the low-temperature side of the back door 74, the amount of heat passing through the back door 74 from inside the heating bag 2a along the thickness direction of the back door 74 to the space on the low-temperature side, which is calculated from the measured values of the power consumed by the heating means 3 and the air blowing means 4, and the area perpendicular to the heat flow in the back door 74.

At this time, if the difference between the ambient temperature inside the heating bag 2a (the high temperature side) and the ambient temperature in the space outside the vehicle (the low temperature side of the back door 74) is 20°C or more, the flow through rate can be calculated with high accuracy.

The above-mentioned heat transfer coefficient measuring method has the remarkable effect of being able to measure the heat transfer coefficient with the doors attached to the car, since the housing of the protective heat box defined in Non-Patent Document 1 corresponds to a car with all doors closed, by controlling the heating means 3 in the heating bag 2a so that the output voltage from the circuit in which the multiple thermopiles 11 attached to the peripheral wall portion 9a of the heating bag 2a are connected in series or the output voltage from the circuit in which the multiple heat flow meters 12 are connected in series becomes zero.

1 Heat transmission coefficient measuring device 1a Heat transmission coefficient measuring device 1b Heat transmission coefficient measuring device 1c Heat transmission coefficient measuring device 2 Heating box 2a Heating box 3 Heating means 4 Air blowing means 6 Box-shaped body 7 Control unit 8 Heating and air blowing means 8a Opening 9 Peripheral wall 10 Thermal insulation performance measurement object 10a Test piece 11 Thermopile 12 Heat flow meter 15 Temperature sensor 16 Temperature sensor 18 Housing 41 Circulating water cooling device 41a Circulating air cooling device 42 Pipe 43 Heat exchanger 44 Baffle 44a Baffle 45 Air blowing means 46 Duct 47 Partition plate 50 Cooling means 60 Light source 61 Glass wall 63 Radiation sensor 70 Heat transmission coefficient measuring device 71 Heating box 72 Protective heat box 73 Heating and air blowing means 74 Back door 80 Automobile 81 Vehicle interior 82 Windshield 83 Front door G cooling air

Claims (13)

A thermal transmission coefficient measuring device for measuring the amount of heat passing from one surface in contact with the high temperature side of an object for measuring thermal insulation performance in the thickness direction to the other surface in contact with the low temperature side,
a heating box having non-permeable and heat-insulating properties, the heating box having a heating means and a blowing means therein, the opening of which is blocked by the installation of the object to be measured for heat insulation performance;
A plurality of temperature measuring means for measuring the atmospheric temperature inside the heating box, which is the high-temperature side of the object to be measured for thermal insulation performance, and the atmospheric temperature in a space, which is the low-temperature side of the object to be measured for thermal insulation performance, respectively;
A control unit that controls the heating means and calculates the heat transmission coefficient,
a plurality of thermopiles or a plurality of heat flow meters are arranged at substantially equal area intervals so that a temperature difference between an inner surface and an outer surface in the entire peripheral wall portion of the heating box can be measured by an output voltage, and a circuit is formed in which the plurality of thermopiles or the plurality of heat flow meters are connected in series;
A thermal conductivity measuring device characterized in that the control unit controls the heating means in the heating box so that the output voltage from a circuit in which the multiple thermopiles or multiple heat flow meters are connected in series becomes zero. The heat transfer coefficient measuring device according to claim 1, characterized in that, when the thickness of the peripheral wall of the heating box is substantially uniform over the entire area, multiple heat flow meters are disposed over the entire inner surface or the entire outer surface of the peripheral wall of the heating box, or multiple thermopiles are disposed over the entire inner surface and the entire outer surface of the peripheral wall of the heating box, one each at substantially equal area intervals. The heat transfer coefficient measuring device according to claim 1, characterized in that, when the thickness of the peripheral wall of the heating box is not uniform over the entire area, multiple heat flow meters are arranged at approximately equal area intervals over the entire inner surface or the entire outer surface of the peripheral wall of the heating box. The heat transfer coefficient measuring device according to any one of claims 1 to 3, characterized in that the setting of the approximately equal area intervals is set such that, when the thermopile is disposed, the entire surface on the inside and outside of the peripheral wall of the heating box is set to the same equal area intervals, or, when the heat flow meter is disposed, the entire surface on the inside or outside of the peripheral wall of the heating box is set to equal area intervals, and the approximately equal area intervals are set as the intervals obtained by dividing the entire surface by any of the equal area division numbers from 5 equal area divisions to 80 equal area divisions. A thermal conductivity measuring device as described in any one of claims 1 to 4, characterized in that the heating box is installed inside a box-shaped body so as to be detachable from the box-shaped body, and the heating box is a heating bag having a bag-like shape with a peripheral wall portion that is non-breathable, insulating, and flexible. The heat transfer coefficient measuring device according to any one of claims 1 to 5, characterized in that the housing forming the low-temperature space is provided with a water-cooling type cooling means that cools the air inside the housing with a heat exchanger, or an air-cooling type cooling means that blows cold air into the housing. The heat transfer coefficient measuring device according to claim 6, characterized in that the wall of the housing forming the low-temperature space facing the object to be measured for thermal insulation performance is provided with a glass wall section that allows radiation from a light source provided outside the housing to the object to be measured for thermal insulation performance inside the housing. The heat transfer coefficient measuring device according to claim 7, characterized in that a plate-shaped baffle plate provided between the glass wall and the object to be measured for thermal insulation performance and approximately parallel to the object to be measured for thermal insulation performance is a glass plate that allows radiation from the light source to the object to be measured for thermal insulation performance. The heat transfer coefficient measuring device according to claim 7 or 8, characterized in that it is provided with a radiation intensity adjusting means for adjusting the intensity of the radiation on the object for which the thermal insulation performance is to be measured inside the housing. The heat transmission coefficient measuring device according to any one of claims 7 to 9, characterized in that a blowing means is provided near the glass wall between the glass wall and the object to be measured for thermal insulation performance, and an airflow speed control means is provided to reproduce the speed of the airflow generated by the blowing means to a wind speed selected from wind speeds under natural conditions. A method for measuring the thermal transmittance of an automobile door using a heating bag, comprising:
The heating bag includes a heating/air blowing means disposed in a substantially central portion and a peripheral wall portion capable of surrounding the heating/air blowing means,
The peripheral wall portion is impermeable, heat insulating, and flexible,
When the thickness of the peripheral wall portion is not uniform over the entire area,
a circuit in which a plurality of heat flow meters are disposed at intervals of approximately equal area obtained by dividing the entire surface on the inner side or the entire surface on the outer side of the peripheral wall portion by any one of 5 to 80 equal area divisions, and the plurality of heat flow meters are connected in series;
The heating bag is placed inside a door opening of a vehicle, and the door is closed so that the peripheral wall portion of the heating bag is sandwiched to block the opening, and the inside of the heating bag is in a closed state. The vehicle door is used as an object for measuring thermal insulation performance,
A method for measuring heat transfer coefficient, characterized in that the heating means in the heating bag is controlled so that the output voltage from a circuit in which the multiple heat flow meters attached to the peripheral wall portion are connected in series becomes zero, and the interior ambient temperature of the automobile is further controlled so that the interior ambient temperature is stabilized, thereby calculating the heat transfer coefficient. A method for measuring the thermal transmittance of an automobile door using a heating bag, comprising:
The heating bag includes a heating/air blowing means disposed in a substantially central portion and a peripheral wall portion capable of surrounding the heating/air blowing means,
The peripheral wall portion is impermeable, heat insulating, and flexible,
When the thickness of the peripheral wall portion is substantially uniform over the entire area,
a circuit in which a plurality of thermopiles are disposed one by one at intervals of approximately equal areas obtained by dividing each of the two inner and outer faces of the peripheral wall by any equal area division number of 5 to 80, and the plurality of thermopiles are connected in series, or a circuit in which a plurality of heat flow meters are disposed one by one at intervals of approximately equal areas obtained by dividing each of the two inner and outer faces of the peripheral wall by any equal area division number of 5 to 80, and the plurality of heat flow meters are connected in series,
The heating bag is placed inside a door opening of a vehicle, and the door is closed so that the peripheral wall portion of the heating bag is sandwiched to block the opening, and the inside of the heating bag is in a closed state. The vehicle door is used as an object for measuring thermal insulation performance,
A method for measuring thermal conductivity, characterized by controlling a heating means in the heating bag so that an output voltage from a circuit in which the multiple thermopiles attached to the peripheral wall portion are connected in series or an output voltage from a circuit in which the multiple heat flow meters are connected in series becomes zero, and further controlling the ambient temperature so as to stabilize the ambient temperature inside the automobile, thereby calculating the thermal conductivity. The method for measuring the thermal conductivity according to claim 11 or 12, characterized in that the door is either a front door, a rear door or a back door.