JPH061280B2 - Fluid condition measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention provides a plurality of detecting elements, each of which has a built-in heating element and detects the temperature of the heating element and / or the temperature of the fluid, in the fluid. It is used to measure the distribution of fluid from the difference in the detected value.For example, the location of fluid, the distribution state of multiple fluids, the interface position between fluids, and the situation of the fluid to be specifically detected It relates to a condition measuring device.

(Prior Art) Conventionally used fluid distribution measurement methods include liquid level measurement using electrodes, liquid level measurement using floating bodies, and liquid volume measurement by air pressure control, as well as fluid and reactive substances. It is known to detect the presence of the fluid by the reaction.

In particular, although the fluid is a liquid and is separated in one tank, the method of detecting the interface or boundary layer is difficult, and visual inspection by a glass tube level gauge is generally used.

In addition, it is difficult to detect the liquid level with liquids that generate bubbles,
Although floating bodies are used and the measuring device is placed in a measuring system in which the liquid is separately branched, this is a situation that is unfavorable for cleaning and preventing bacterial contamination. Have a hard time.

In measuring the distribution of a fluid such as the presence of a fluid or the liquid level, interface, boundary layer, etc., easy cleaning and no bacterial contamination are requirements for various production facilities.

Therefore, it was considered to utilize the thermal measurement method of the fluid that the applicant has conventionally proposed.

The applicant of the present invention has proposed a liquid level measuring method in Japanese Patent Laid-Open No. 62-27622. In this proposal, a sensor contacted with a thin metal wire that is in thermal contact with a liquid is a contact range with the liquid. Discloses a method in which it is possible to measure a liquid level by showing a temperature change and associating the temperature with the change in the liquid level.

The applicant has also proposed JP-A-62-185146 as a method for measuring the state of a fluid, and has made it clear that the composition, physical properties, viscosity, etc. of the fluid can be detected by an element that is in thermal contact with the fluid. It was As this specific detecting device, Japanese Patent Laid-Open No.
No. 44838 proposes a rod-shaped sensor in which a sensor element composed of a thin metal wire is electrically insulated and arranged in a state of good thermal conductivity.

Further, the sensor is capable of detecting the temperature of the heating element by the heating element itself, but since the temperature of the heating element is measured by a separate temperature detecting element, a sensor having a built-in temperature sensing element is applied for at the same time. Proposed in No. 1-55648.

Further, as a planar sensor, there is JP-A-63-215958.

(Problems to be Solved by the Invention) When measuring the distribution of a fluid by using the above-mentioned conventional technique, the measuring device is distributed to appropriate portions of the tank and arranged at a plurality of locations, or separate measurement portions are branched. However, even if the cost of the measuring device is enormous, the problem that the distribution details cannot be measured occurs.

This is because the arrangement of multiple measuring devices is not a solution that can detect fluctuations in the distribution of fluid, so even if there are fluctuations in the fluid when measuring distribution, the liquid level, interface, boundary tank, etc. can be accurately measured. Need to be detectable.

In the liquid level measuring method of Japanese Patent Laid-Open No. 185146/1987 developed by the applicant of the present invention, a sensor composed of a thin metal wire is vertically arranged in the liquid and the liquid level is detected by the temperature thereof. However, since the temperature of the entire sensor is detected as one temperature, it can be used only with a liquid of a certain composition, and in the case of bubbles or the separation of multiple liquids in a tank, the liquid surface or the interface of each liquid , Not available for detecting boundary layers.

This is because the sensor shows a temperature change under the influence of heat transfer of bubbles and other liquids.

Therefore, when trying to measure the distribution of fluid,
When using a technology that uses thermal contact, it is necessary to configure a plurality of sensors so that thermal effects do not interfere with each other. If a plurality of sensors are arranged, the equipment cost is enormous and cleaning is difficult.
For this reason, branching design equipment may be provided, but the problems of cleaning and bacterial contamination still occur.

Therefore, the present invention is easy to clean, does not require equipment configuration that causes bacterial contamination, and is in thermal contact with the fluid,
Provides a means for measuring the distribution of fluids that enables the measurement of interfaces and boundary layers where multiple fluids are mixed and split, the measurement of bubbles and liquid surfaces of liquids that produce bubbles, and the detection of the location of fluids. The purpose is to do.

(Means for Solving the Problem) Therefore, as a means for solving the above problem, a plurality of detecting elements, each having a built-in heating element and detecting the temperature of the heating element and / or the temperature of the fluid, are formed on the wall surface of the support so as to prevent unevenness. A control in which the temperature of the planar detection element or the temperature difference between the temperature of the planar detection element and the temperature of the fluid is measured and the distribution of the fluid can be measured by comparing the temperature of each detection element or the temperature difference. The entire surface detection element was connected to the apparatus to form a fluid state measuring apparatus.

(Operation) The present invention relates to a sensor in which a plurality of elements having a heat distribution body that is in thermal contact with a fluid are arranged, and the temperature of the heating element of each element or the temperature of the heating element of each element and its The state of the fluid is measured by detecting the difference in temperature of the fluid with which the element is in contact and comparing them.

Specifically, when a fluid is in thermal contact with an element containing a heating element and heat is transferred, the heat transfer state changes due to changes in the composition, viscosity, and physical properties of the fluid, causing the temperature of the heating element and the temperature of the heating element to change. The difference between the temperature of the fluid and the temperature of the fluid is used. It utilizes the fact that the difference in temperature between the two is different.

That is, it is possible to detect the liquid level of the fluid by utilizing the difference in the detection values of the element in contact with the fluid and the element in contact with the gas, and multiple fluids exist separately. In doing so, the distribution of the fluid at the position of each detection element can be measured by showing different detection values depending on the fluid with which the plurality of detection elements are in contact.

That is, the temperature of the heating element of each element and the temperature of the liquid with which the element is in contact are basically detected to obtain the temperature of the heating element or the difference between the temperature of the heating element and the temperature of the fluid, and compare them. It is a position where each element discriminates the heterogeneity of the fluid with which it comes into contact.

Further, when a plurality of fluids exist separately, the temperature of the fluid at the position of each detection element can be known and its distribution can be measured by indicating different temperatures depending on the fluids in contact with the plurality of detection elements.

In particular, since the detection element is a planar detection element, the temperature also varies depending on the contact area with the fluid, and when the fluid is a liquid, fine measurement can be performed for interface measurement.

(Example) Hereinafter, the Example of this invention is described based on drawing.

First, using a rod-shaped detection element, the temperature of the heating element of the detection element and the temperature of the fluid in contact with the element are basically detected to determine the temperature of the heating element or the difference between the temperature of the heating element and the temperature of the fluid. It will be described from the determination and comparison of these to determine the heterogeneity of the fluid in contact with each element.

FIG. 1 shows a measuring device (1). (2) is a support, and the one shown in the drawing has a cylindrical shape.
A large number of detection elements (3) are provided on the side surface of the support body (2). The detection elements (3) are radially arranged so as to be separated from each other in the horizontal direction and the vertical direction, and the detection elements (3) adjacent to each other are separated from each other as much as possible so as not to affect each other by heat. It has become. In order to eliminate the influence of heat between the detection elements (3), it is desirable that the support body (2) is composed of a heat-defective conductor, but the detection element (3) has heat failure relative to the support body (2). You may make it supportive. Further, an insulator may be filled in the support body (2) to which the detection element (3) is attached.
In addition, the upper end of the support body (2) is a mounting portion (4) in which a screw thread is formed on the peripheral edge.

FIG. 3 shows the support (2) to which the detection element (3) is not attached, and (5) is the attachment port of the detection element (3). Threads are formed on the inner surface of the mounting port (5). An upper lid (7) and a lower lid (7) are screwed onto the upper and lower sides of the support body (2), and the upper lid (6) has a hole for passing a lead wire of a detection element (3) described below. (8) is drilled.

Next, FIG. 4 shows a detection element (3),
Reference numeral (10) is a detection element main body, in which a heat generating / temperature measuring element (11) is incorporated. Sensing element body (10)
Has a threaded portion (12) at its base end, and the threaded portion (12) is inserted into the mounting opening (5) on the side surface of the support (2) and the nut (13) is turned to detect the detection element. (3) can be attached to the support (2). Fifth
The figure is a cross-sectional view of the heat-generating / temperature-measuring body (11). (15) is a heat-generating / temperature-measuring body case, and (16) and (17) are arranged in the heat-generating / temperature-measuring body case (15). It is a heating element and a temperature measuring element. The temperature sensing element (17) may be a thermocouple, a resistance temperature detector, a thermometer, etc., but the one shown in the figure is constituted by the heating wire of the heating element (16). ) Is composed of a resistance temperature detector. The case (15) is filled with an insulator (18) that is a good conductor of heat and has an insulating property, so that the heating element (16) and the temperature measuring element (17) are prevented from leaking electricity. ing. As shown in FIG. 4, these heating element (16) and temperature measuring element (17) have lead wires (1
9) is connected, a predetermined current is supplied to the heating element (16) and the temperature measuring element (17) by a control device (not shown) provided outside the measuring apparatus (1), and the voltage value thereof is supplied. The temperature can be measured from the etc. If the heating elements (16) of each detection element are wired in series, it is convenient because all the heating elements (16) can generate heat at the same time. Lead wire as above (19)
Are drawn out from above the support (2) through the hole (8) described above with reference to FIG. Then, FIG. 6 shows that the measuring device (1) having the above-described structure is mounted on the fluid tank (T), and the fluid (f) in the fluid tank (T) is
Fig. 2 shows an example of a mode for measuring the distribution of each layer (f1) by each detection element (3) mounted on the support (2).
It is possible to know the positions of (f2) and (f3) and the separation layer. Further, the measuring device (1) can be easily mounted by using the mounting portion (4) at the upper end of the support body (2) and screwing it onto the upper surface of the fluid layer (T).

Here, the relationship between the position of the separation surface and the temperature of the detection element (3) will be described with reference to FIGS. 7 and 8 as follows.

That is, FIG. 8 shows a case where a plurality of detecting elements (3A) to (3F) are arranged in a plane arrangement and are arranged as shown in FIG.
When the separation surfaces of the two liquids are I, II, and III, the temperatures of the detection elements (3A) to (3F) are shown.

For example, when the specific heat of the upper fluid is small and the specific heat of the lower fluid is large, if the separation surface is I, the uppermost detection element
Since only the temperature of (3A) is high and the temperatures of the other detection elements (3A) to (3F) are low, it can be seen that there is a separation surface between the detection element (3A) and the detection element (3B). Further, if the separation surface is II, to the detection element (3C) and the detection element (3D), if the separation surface is III, a temperature difference occurs between the detection element (3D) and the detection element (3E),
You can know the existence of the separation plane. Therefore, if the separation surface exists between any of the detection elements, the position of the separation surface can be known from the position of the detection element.

The temperature of each detection element is a material for comparison and determination for knowing in which temperature range the detection element exists, and it is not always necessary to know the temperature itself accurately. Further, as described above, the position of the separation surface can be known based on the temperature, because the transfer state of the heat generated from the heating element (16) built in the detection element varies depending on the fluid. This is because the temperature of the detection element is different if the difference is different.

The above is basically the temperature of the heating element of the square element and the temperature of the fluid in contact with the element are detected to find the temperature of the heating element or the difference between the temperature of the heating element and the temperature of the fluid, and this is compared. It is shown that it is possible to determine the heterogeneity of the fluid with which each element contacts. In the apparatus for measuring a fluid state according to the present invention, in particular, a sheet-like detecting element is used, and a plurality of the sheet-like detecting elements are arranged so as not to cause unevenness on the wall surface of the support, and the temperature of the sheet-like detecting element or the sheet-like detecting element The present invention provides a fluid state measuring device for measuring a temperature difference between a temperature of a fluid and a temperature of a fluid, and comparing a temperature or a temperature difference of each detection element to measure a fluid distribution.

FIG. 9 shows a measuring device (1) according to another embodiment of the present invention, in which the detecting element (3) is formed in a planar shape, and the detecting element (3) is arranged in a rectangular cylindrical support (2). It is shown that the respective side surfaces are arranged in a staggered manner so as not to cause unevenness. A heat transfer plate (20) is embedded on the same surface on each side of the support (2), and a heating element (21) and a temperature measuring element (22) are mounted inside the heat transfer plate (20). Has been done. In addition, as shown in the figure, the heating element (21) and the temperature measuring element (2
Instead of stacking 1), both may be directly attached to the heat transfer plate 20.

As shown in FIG. 11, the heat generating element (21) and the temperature measuring element (22) are covered with an insulating material (23) so as not to leak electric current between them. In addition, the heating element (2
A lead wire (24) is connected to the temperature measuring element (1) and the temperature measuring element (22), and the heating element (21) and the temperature measuring element (21) are controlled by a control device (not shown) provided outside the measuring device (1). A predetermined current is supplied to the body (22), and the temperature can be measured from the voltage value or the like.

The support (2) may be a cylindrical body or a rectangular tube, but if the detecting element on each side face is oriented in a direction different from that of the detecting elements on the other side, the heat transfer direction to the fluid may be different. In other words, it is preferable to minimize the influence of heat generation on the detection element on the other side.

As shown in the figure, the detecting element (3) of this embodiment has an inverted triangular shape, but the detecting element (3) may have a crescent shape as shown in FIG. It is possible to adopt any shape such as. However, as shown in FIG. 9 and FIG. 12, it is possible to improve the detection accuracy with high accuracy by making the upper part wide and the lower part small.

Further, as in this embodiment, by arranging so that the detection elements (3) on the adjacent side surfaces have an overlapping area at the same height position of the support (2), an accurate position of the separation surface can be obtained. It becomes possible to detect.

That is, the crescent-shaped detecting element (3A) as shown in FIG.
When (3F) is arranged on each side surface of the support (2) so that adjacent detection elements have an overlapping area, for example, the specific heat of the upper fluid is small and the specific heat of the lower fluid is When the separation surface is at the position I when the temperature is large, the temperature of the uppermost detection element (3A) becomes high, and the second detection element (3A) becomes
The temperature of (B) is close to the temperature of the detection element (3A), but it becomes a little lower than that, and the other detection elements (3D) (3E)
(3F) becomes a completely low temperature. Also, if the separation surface is at the position II, the temperature of the first and second detection elements (3A) (3B) will be higher, the temperature of the third detection element (3C) will be lower, and The sensing elements (3D) (3E) (3F) are completely cold. Also, if the separation surface is at position III, the temperature of the first and third detection elements (3A) ~ (3C) is high, the temperature of the fourth detection element (3D) is slightly lower than that, The temperature of the fifth detecting element (3E) is almost low, and the temperature of the lowermost detecting element (3F) is completely low. The relationship between the temperatures of the respective detecting elements (3A) to (3F) as described above is shown in FIG. 13, and the accurate position of the separation plane can be known by the lines I, II and III.

The correlation between the temperature of each of the detection elements and the position of the separation surface shows the same relationship for the same fluid,
When the composition, physical properties, viscosity, etc. of the fluid to be measured change, it is necessary to understand the relationship by conducting preliminary experiments in advance, but in any case, it is detected by each detection element. From the determined temperature gradient, it is possible to know the exact position of the separation plane based on the correlation. The detection elements may be inaccurately detected unless they are thermally defective conductors.

In the device of the present invention as described above, the support body (2) has a cylindrical body as shown in the figure,
The wall surface of the fluid tank (T) can also be used as a support. Further, the detecting element (3) can be arranged not on the cylindrical body but on a flat body. However, whichever method is adopted, in order to improve the detection accuracy, it is necessary to prevent the heat generation effects of the detection elements from affecting each other.

Further, the measuring apparatus of the present invention can measure each interface even when a plurality of fluid interfaces are generated, and can detect the liquid level in the liquid tank. is there. In that case, the fluid is the first fluid, and the gas in the upper space is the second fluid. Further, even when the liquid produces bubbles, the liquid surface and the interface between the bubbles and the gas can be detected. Further, for example, when it is desired to separate the slurry or the like and the liquid and detect the amount thereof,
It is also possible to arrange the measuring device of the present invention in a stationary system and detect the interface between the slurry and the liquid to calculate the amount of the slurry. Further, the culture tank and the like are airtight and easily generate bubbles such as medium, but by disposing the measuring device of the present invention in the culture tank, the medium and bubbles can be detected separately, and aseptic supply control Will be possible. As described above, the present invention can detect the state of fluid classification and distribution in all fields.

(Effects of the Invention) Therefore, the following effects can be achieved in the present invention.

Interfaces and boundary layers can be detected in a system in which multiple types of fluid exist separately, which is automatic compared to visual measurement using a glass tube, and output signals to other control devices can be detected. .

When arranging a plurality of detection elements, the cost is enormous, and the wiring and the control system are complicated, but according to the present invention, this can be made inexpensive and simple, and the versatility is increased. .

Since it is easy to clean and it is not necessary to branch the measurement system, the problem of bacterial contamination can be solved.

It is possible to accurately grasp the liquid level of the liquid in which bubbles are present, and prevent malfunction in the liquid tank or the like.

Detecting the distribution of the existence of multiple fluids using a conventional sensor with a built-in heating element will cause an erroneous detection under the influence of other fluids when multiple fluids are present. Detects each position,
The influence from others can be eliminated.

In addition to the above, the present invention has the following effects.

That is, the temperature of the planar detection element itself varies depending on the contact area with the fluid, and the fluid distribution can be measured more finely than the rod-shaped detection element.

When the fluid is a liquid, etc., it is possible to make detailed measurements especially for the interface measurement.

Further, in the planar detection element of the present invention, the arrangement of the detection elements can be continuously performed to perform the whole measurement, and the range of the measurement portion can be expanded and continuously performed.

[Brief description of drawings]

1 and 2 are front and bottom views of the measuring device, FIG. 3 is a longitudinal sectional view of a support, FIG. 4 is a sectional view of a detecting element, FIG. 5 is a sectional view of a heat-generating / temperature-measuring body, and FIG. FIG. 6 is a sectional view of the fluid tank, FIG. 7 is an explanatory view of the arrangement position of the detection element, FIG. 8 is a graph showing the relationship between the liquid separation surface and the temperature of each detection element, and FIGS. 11 is a front view and a bottom view of the measuring device according to the present invention, FIG. 11 is a perspective view of a heating element (temperature measuring element), FIG. 12 is an explanatory view of the arrangement position of the detection element, and FIG. 13 is a liquid separation surface and each detection element. It is a graph showing the relationship of the temperature of. 1 ... Measuring device, 2 ... Support, 3 ... Detection element, 10
...... Detecting element body, 16, 21 …… Heating element, 17, 22
...... Temperature detector,

Claims (1)

[Claims] 1. A plurality of sheet-like detecting elements having a built-in heating element for detecting the temperature of the heating element and / or the temperature of a fluid are arranged on the wall surface of the support so as not to cause unevenness. Or the temperature difference between the temperature of the planar detection element and the temperature of the fluid is measured, and the planar detection element is connected to a control device capable of measuring the distribution of the fluid by comparing the temperature of each detection element or the temperature difference. A device for measuring the state of a fluid.