JPH0415898B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a device for measuring in real time the amount of dry suit such as carbon particles and soluble organic matter (hereinafter referred to as SOF) contained in the exhaust gas of a diesel engine. be.

Prior Art Conventionally, the concentration of dry suits and SOF in exhaust gas has been measured as follows. First, particulates in the exhaust gas are collected on a filter, the temperature and humidity of this filter are adjusted, and then the particulate concentration is measured by weighing with a chemical balance. Next, SOF is extracted from the particles on the filter using a Soxhlet device, and the concentration of the dry suit and SOF is determined from the weighed results. However, due to this type of processing, it takes time to measure the concentration of dry suits and SOF, and it is impossible to grasp concentrations that change from moment to moment, making it difficult to comply with strict exhaust gas regulations for diesel engines. Have difficulty.

However, the present applicant has already proposed a dry suit and a device for measuring the concentration of SOF in real time in Japanese Patent Application No. 58-203641. This involves diluting and mixing the exhaust gas with a large amount of clean air in a dilution tunnel, and then guiding this diluted mixed gas to the first and second detection means, and the first detection means detects the amount of dry suit in the exhaust gas. The second detection means detects SOF in the exhaust gas, and these detection means measure the concentration of the dry suit and SOF based on the pressure loss across the filter.

Problems to be Solved by the Invention In the proposed device, there is a problem in that when the amount of exhaust gas from the engine fluctuates, the pressure in the dilution tunnel fluctuates, which causes errors in measuring the concentration of the dry suit and SOF.

Means for Solving the Problems The device of the present invention dilutes and mixes the exhaust gas of a natural engine with a large amount of clean air in a dilution tunnel, and then guides this diluted mixed gas to first and second detection means, and This is a particulate emission measurement device for a vehicle in which the detection means detects the amount of dry suit in the exhaust gas, and the second detection means detects soluble organic matter in the exhaust gas. The first detection means includes a first sampling pipe for taking out a part of the diluted mixed gas from the diluted tunnel, a first sampling pump for flowing the diluted mixed gas into the first sampling pipe, and the first sampling pipe. a first filter installed in the middle of the pipe to collect the dry suit;
A first heating means provided upstream of the first sampling pipe from the first filter, a first differential pressure converter for detecting a pressure difference before and after the first filter, and a first differential pressure converter provided downstream of the first filter. a first throttling mechanism that suppresses the amount of fluctuation based on pressure fluctuations in the first sampling pipe, which is provided between the side pressure extraction part and the first differential pressure converter; and a time differential of the signal of the pressure difference. and a first calculation device that calculates the amount of dry suit in the exhaust gas based on the value. 2nd above
The detection means includes a second sampling pipe for taking out a part of the diluted mixed gas from the dilution tunnel, a second sampling pump for causing the diluted mixed gas to flow into the second sampling pipe, and a part of the second sampling pump. a relatively large auxiliary filter that is provided in the auxiliary filter to collect the dry suit; and a second heating means that is provided upstream of the second sampling pipe than the auxiliary filter;
a second filter that is provided downstream of the auxiliary filter to collect soluble organic matter; a second differential pressure converter that detects the pressure difference before and after the second filter;
a second throttling mechanism that is provided between a pressure extraction section on the upstream side of the second filter and the second differential pressure converter and suppresses an amount of fluctuation based on pressure fluctuation in the second sampling pipe; and a second calculation device that calculates the amount of soluble organic matter in the exhaust gas based on the time differential value of the difference signal.

Example The present invention will be explained below based on illustrated embodiments.

FIG. 1 shows a first embodiment of the present invention. In this figure, an exhaust pipe 2 extending from a diesel engine 1 branches into two at a split valve 3, one of which is connected to an exhaust port 4 and the other communicated with a dilution tunnel 5. Therefore, the exhaust gas discharged from the engine 1 is divided at the division valve 3 and discharged from the exhaust port 4, while a portion is supplied into the dilution tunnel 5.

The dilution tunnel 5 mixes the air taken in from the intake port 2 and the exhaust gas taken in from the branch pipe 7 of the intake pipe 2. The diluted mixed gas formed by mixing the exhaust gas and air is passed through a roots blower (not shown). etc., and flows at a constant speed in the direction of arrow A. A thermometer 8 is installed in the middle of the dilution tunnel 5 to detect the temperature inside the tunnel, and first and second sampling pipes 10, 30
The tip of is facing you. These sampling pipes 1
0 and 30 are for taking in the diluted mixed gas and detecting the amount of dry suit and SOF in the exhaust gas, respectively.

A first sampling pump 11 is installed on the downstream side of the first sampling pipe 10 to suck the diluted mixed gas at a constant flow rate, and inside this pump 11 are a buffer tank for absorbing pulsation, a flow meter, and a computing unit. Equipment such as these will be installed. The first sampling pipe 10 is provided with a valve 12 in a portion close to the dilution tunnel 5, a coil heater 13 immediately downstream of the valve 12, a first filter 14 downstream of the coil heater 13, and a first filter 14 immediately upstream of the first filter 14. A temperature sensor 15 is attached to the side. A front pressure detector 16 is located upstream of the first filter 14.
However, a rear pressure detector 17 is also provided on the downstream side. The front pressure detector 16 is connected to a filter case 52 via a hose 51. The filter case 52 accommodates a control filter 53 and has a portion open to the atmosphere. The filter case 52 also communicates with one end of the capillary tube 54,
The other end of the capillary tube 54 is connected to the first differential pressure transducer 18 . On the other hand, the rear pressure detector 17 is directly connected to the first differential pressure converter 18 via a hose 55. Thus, the first differential pressure converter 18 converts the differential pressure across the filter 14 into a predetermined signal, and outputs this to the first calculator 19. This computing unit 19
A temperature detector 15 and a first sampling pump 11 are also connected to. The first filter 14 collects the dry suit, and the amount of dry suit collected is determined based on the pressure difference before and after the filter 14, as will be described later. Note that the electric power supplied to the coil heater 13 is adjusted by the slider 20.

A mechanism similar to that of the first sampling pipe 10 is provided on the downstream side of the second sampling pipe 30 as well. That is, a second sampling pump 31 similar to the first sampling pump 11 is provided at the most downstream side, and a valve 32 is installed at a portion near the dilution tunnel 5. Also valve 3
A coil heater 33 is provided immediately downstream of the coil heater 33, a second filter 34 is provided downstream of the coil heater 33, and a temperature detector 35 is provided immediately upstream of the second filter 34. A front pressure detector 36 is provided on the upstream side of the second filter 34, and a rear pressure detector 37 is provided on the downstream side of the second filter 34.
is provided. The front pressure detector 36 is connected to the hose 61
It is connected to a filter case 62 via a filter case 62, which accommodates a control filter 63 and partially opens to the atmosphere.
Also, the filter case 62 is the capillary tube 6.
4, and the other end of the capillary tube 64 is connected to the second differential pressure converter 38. On the other hand, the rear pressure detector 37 is directly connected to the second
It is connected to a differential pressure converter 38. This second differential pressure converter 38 , second sampling pump 31 , and temperature detector 35 are connected to a second computing unit 39 .
Further, a slider 40 is connected to the coil heater 33.

The functions of these mechanisms are basically the same as those provided downstream of the first sampling pipe 10, but the second filter 34 is the same as the one provided downstream of the first sampling pipe 10.
Unlike 4, it collects SOF. Second filter 34
In order to collect only SOF, an auxiliary filter 41 for collecting dry suit is installed upstream of the second filter 34 and immediately downstream of the coil heater 33. This auxiliary filter 41 has the same material and composition as the first filter 14, but its diameter is several times larger than that of the first filter 14. Note that the auxiliary filter 41 and the second filter 3
4, a relatively long cooling pipe 42 is provided.

Next, we will explain that by heating the exhaust gas, particles in the exhaust gas can be separated into dry suits and SOF. FIG. 2 shows an experimental apparatus for determining the relationship between the collected matter on the filter and the temperature in front of the filter.A filter 72 is located downstream of a sampling pipe 71, and a temperature detector 73 is immediately upstream of this filter 72. , coil heaters 74 are provided upstream of the temperature detectors 73, and the coil heaters 74 are supplied with electric power by a variable DC power source 75. Exhaust gas is sucked into the sampling pipe 71 in the direction of arrow B, and is discharged through the filter 72. Here, the temperature in front of the filter 72 is changed by adjusting the variable DC power supply 75.

Figure 3 shows the temperature in front of the filter 72 and the filter 7.
2 shows the relationship with the accumulated weight of the collected material on 2. In the figure,
The shaded area indicates the weight of the deposit after Soxhlet extraction of the filter 72 with dichloromethane without heating, that is, when only dry suit is collected on the filter 72. Other items that are not shaded indicate the weight of deposits without Soxhlet extraction. From this figure, the deposited weight is the highest when not heated by the coil heater 74, and as the temperature increases, the deposited weight decreases, and becomes approximately constant at 200°C or higher, which is the same as in the case of Soxhlet extraction. It can be seen that the temperature in front of the filter 72 is 200℃
In this case, only the dry suit is collected on the filter 72, and the SOF passes through the filter 72, and the particulates in the exhaust gas are separated into the dry suit and the SOF.

This SOF can be cooled and condensed in a suitably extended sampling pipe and collected by a filter installed in the middle of this pipe, and in the embodiment shown in FIG. A cooling pipe 42 is provided.

Next, the dry suit and
The relationship between the accumulated weight of SOF and the differential pressure before and after the filter will be explained. Generally, it can be easily estimated that the ventilation resistance of the filter will increase as the amount of particles deposited on the filter increases, but the present invention will not work unless there is a quantitative relationship between the two. Also, when fine particles of the same weight are deposited,
It is thought that the ventilation resistance will differ if the properties of the particles differ, and the properties of the dry suits and SOF discharged from diesel engines may also change depending on the operating conditions. Figures 4 and 5 show the experimentally determined dry suit and
Collection amount of SOF and pressure loss in the filter △
It is a graph showing the relationship between P. A, A', and B in the diagram
, B', C, and C' respectively show the relationship between the amount of collected particulates and the pressure loss ΔP under engine operating conditions of 1000 revolutions and low load, 2000 revolutions and medium load, and 3000 revolutions and high load. Furthermore, the portions indicated by D and D' indicate the ventilation resistance of the filter itself. As is clear from Figures 4 and 5, the pressure loss △P of the auxiliary filter has a very good proportional relationship with the amount of dry suit and SOF collected, and it can be seen that it is not affected much by the engine operating conditions. .

In addition, the temperature before the filter in Figure 4 is 255℃,
The temperature before the filter in FIG. 5 is 45°C.
The sampling gas flow rate is 20°C at 25°C.
/minute.

Using the pressure loss characteristics of the filter described above, the dry suit and the
To know the SOF emission status, that is, the ever-changing dry suit and SOF emission amount per unit time, you can do the following. Calculate the weight of dry suit or SOF particles emitted per unit time.
If W′, W′ is expressed by the following equation (2).

W'=m×(Q+q)...(2) where W': Amount of particulate emissions per unit time (mg/sec, etc.) m: Weight of particulates in unit volume of sampling gas (mg/sec, etc.) Q: Dilution Mixed gas blower flow rate (m ³ /sec, etc.) q; Sampling gas flow rate (m ³ /sec, etc.) Among the large amounts included in (2) above, the particle weight m in the unit volume of sampling gas during sampling is determined by the conventional method. However, considering the pressure loss characteristics of the filters 14 and 34 described above, it can be determined as follows. filter 14,
Since the pressure loss of 34 is proportional to the amount of particles collected and proportional to the flow rate, the increase in pressure loss d(△P) of the filter during the minute time dt is as follows: d(△P) = K・m・q・dt・q...(3) △P: Pressure loss (Kg/m2 ^{, etc.} ) K: Constant determined by filter diameter and other factors m・q・dt: Weight of fine particles collected by the filter during dt (mg, etc.) ). From equation (3), m can be found using equation (4) below.

m=1/K・q ²・d(△P)/dt...(4) K: Constant determined by filter diameter, etc. d(△P)/dt: Time differential value of filter pressure loss Sampled using equation (4) By determining the weight m of particulates in a unit volume of gas, the amount of particulates emitted moment by moment during mode driving can be determined using the above-mentioned equation (2). Note that the blower flow rate Q of the diluted mixed gas and the sampling gas flow rate q included in equation (2) take approximately constant values during the test, so they can be treated as constants.

To summarize the above, by determining the time differential value of the pressure loss of the filters 14 and 34, which has the characteristics of being proportional to the amount of collected particles and proportional to the sampling gas flow rate, the dry suit in the unit volume of the sampling gas is You can know the weight of the dry suit and SOF, and ultimately the amount of emissions of the dry suit and SOF while driving in the mode.

Next, the operation of the above embodiment will be explained.

First, at the start of mode driving, valves 12 and 3
2 is opened, the diluted mixed gas is drawn into the first and second sampling pipes 10, 30, and heated to 200° C. or higher by the coil heaters 13, 33.
The heated gas passes through the first filter 14 and the auxiliary filter 44, which collect the dry suit. On the other hand, SOF passes through filters 14 and 44,
The SOF that has passed through the first filter 14 is collected by a filter (not shown) in the sampling pump 11, and the SOF that has passed through the auxiliary filter 41 is collected by the second filter 34 after passing through the cooling pipe 42.

The pressure on the upstream side of each of the first and second filters 14, 34 is determined by the hose 5, as described later.
1, 61, control filters 53, 63, and capillary tubes 54, 64, fluctuating components are removed, and the pressure on the downstream side of each of the first and second filters 14, 34 is transferred to the hose 55, 65, the fluctuation components are removed. Thus, the differential pressure across the first filter 14 is input to the first differential pressure converter 18, converted into a corresponding signal, and input to the first calculator 19. Similarly, the differential pressure across the second filter 34 is input to the second differential pressure converter 38, where it is converted into a corresponding signal and the second
It is input to the computing unit 39. These computing units 19,
39 further receives signals from the temperature detectors 15, 35 and signals indicating sampling flow rates from the sampling pipes 11, 31. In this way, the temperature in front of the filters 14, 34 is calculated by the calculator 19,
The purpose of inputting each value into 39 is to correct the increase in differential pressure based on this temperature, since the volume and viscosity of the gas increase as the gas temperature increases, and the differential pressure across the filter increases. The relationship between this temperature and the increase in differential pressure based on temperature is △P=aT+b under the condition of constant mass flow rate, and this △P is subtracted from the differential pressure determined by the differential pressure converters 18 and 38. Perform temperature correction. However, T is the absolute temperature,
a and b are constants determined by the sampling flow rate and the type of filter.

The first and second computing units 19 and 39 receive the above-mentioned signals and calculate the dry suit and
By determining the weight of the SOF and reading it, it is possible to know in real time the amount of dry suit and SOF discharged while the vehicle is running.

Here, the functions of the control filters 53, 63 and the capillary tubes 54, 64 will be explained.

FIG. 6 shows an electric circuit equivalent to the acoustic circuit including the vicinity of the first filter 14 and the first differential pressure converter 18 and the first sampling pump 11 of the embodiment shown in FIG. In this FIG. 6, the constant voltage source 81 is equivalent to the sampling pump 11,
Resistors 82, 83, and 84 are connected to the first filter 1, respectively.
4 corresponds to the control filter 53 and the capillary tube 54, and the resistors 85 and 86 correspond to the hoses 51 and 55, respectively. On the other hand, the constant voltage source 87 corresponds to the filter case 52 being opened to the atmosphere, and the capacitors 88 and 89 correspond to the differential pressure converter 1.
It has a capacity corresponding to the hoses 51 and 55 connected to 8. R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ indicate the resistance values of resistors 82, 83, 84, 85, and 86, respectively, and i ₂ , i ₃ , i ₄ , i ₅ , and i ₆ Resistor 82, respectively.
The magnitude of the current flowing through 83, 84, 85, and 86 is shown. Pt is the upstream pressure of the first filter 14 in the sampling pipe 10, and since this is approximately equal to the pressure in the dilution tunnel 5, it will be treated as the pressure in the dilution tunnel hereinafter. Pp and Pr are the pressures in front and behind the differential pressure transducer 18. Note that the sampling pump 11 has a constant flow rate in a steady state, so a constant current source is used, but if the dilution tunnel internal pressure Pt changes suddenly,
Since the capacity of the pump cannot be changed rapidly, a constant voltage source is considered suitable here.

First, consider the state of Pt=Pp. This state is a state in which there are no resistors 83 and 84, that is, a state in which this state control filter 53 and capillary tube 54 are not attached. If the engine is stopped and the flow rate of the Roots blower is changed to cause pressure fluctuations in the dilution tunnel 5, as occurs during mode driving, Pp will fluctuate finely as shown in Figure 7. On the other hand, Pr does not fluctuate minutely, and the differential pressure (Pr-Pp) cannot be kept constant. This is Pr is resistance 8
2, 86, and the capacitor 89 to remove and smooth the fluctuation components, and even though fine particles are not deposited on the first filter 14,
The calculation unit 19 calculates the amount as if it were deposited. In other words, if there is pressure fluctuation in the dilution tunnel due to mode driving, a measurement error will occur.

By preventing such measurement errors, even if the dilution tunnel pressure Pt fluctuates, the differential pressure across the differential pressure converter (Pr−
Pp) must have the same value as the differential pressure caused by the accumulation of particles on the first filter 14, that is, the potential difference R ₂ ·i ₂ across the resistor 82. As mentioned above, the resistors 83 and 84 act to approximately show the relationship Pr−Pp=R ₂ · i ₂ .
Constant voltage source 87 and capacitor 88, that is, control filter 53 and capillary tube 5
It is 4. In other words, the dilution tunnel internal pressure Pt fluctuates as the sum of an AC component and a DC component. Adjustment is made by the action of the constant voltage source 87 and resistor 83 of the open control filter 53.

In other words, among the fluctuation components of the dilution tunnel pressure Pt, the alternating current component is smoothed by the resistors 82 and 86 and the capacitor 89 in FIG. 6, and becomes the pressure after the differential pressure converter.
Similarly, resistances 84 and 85 affect Pr.
is smoothed by the capacitor 88 and influences the differential pressure converter front pressure Pp, and these influences are caused by the resistance R ₄ ,
By selecting the size of _R5 , it is possible to make them approximately the same. Also, the internal pressure of the dilution tunnel
Considering the case where the DC component △Pt of Pt suddenly decreases, the current i ₂ passing through the resistor 82 will decrease accordingly △i ₂
, and the pressure Pr after the differential pressure converter becomes (△Pt＋R ₂・
△i ₂ ), and the differential pressure converter front pressure Pp is reduced by the resistance 85, 84 and the capacitor 88.
If only ΔPt is provided, only ΔPt will decrease, and the differential pressure between the two (Pr−Pp) cannot be kept constant. However, in this embodiment, by adding the constant voltage source 87 and the resistor 83,
Resistance 83 as the pressure inside the dilution tunnel decreases Pt
By increasing the current i ₃ passing through by △i ₃ , R ₃・△
The pressure Pp in front of the differential pressure converter is lowered by i ₃ so that this value becomes almost the same as the value of R ₂ ·Δi ₂ to keep the differential pressure (Pr−Pp) constant. In other words, when the DC component of the dilution tunnel pressure Pt decreases by △Pt, the decreases in the pressures Pp and Pr before and after the differential pressure converter are (△Pt + R ₂ · △i ₂ ) and (△Pt +
R ₃・△i ₃ ), where R ₂・△i ₂ ≒R ₃・△i ₃
Therefore, the differential pressure (Pr-Pp) can be kept constant.

According to experiments conducted by the inventors, the relationship between the currents i ₃ and i ₂ , that is, the flow rate of air flowing in from the air-opened end of the filter case 52 and the flow rate in the sampling pipe 10, is that the former is at most 2% of the latter. It's like a degree. Therefore, the flow rate of the sampling pump 11 may be increased by about 2% in advance. Furthermore, since the resistance R ₂ of the filter 14 increases with the accumulation of particles, it is not possible to cancel out the fluctuations in the alternating current and direct current components of the dilution tunnel internal pressure Pt throughout the mode running, so the resistance R ₂ during the mode running increases. It is preferable to select the resistance value of the control filter 53 and the resistance value of the capillary tube with respect to the average value of .

Although the differential pressure across the first filter 14 has been described above, the same applies to the differential pressure across the second filter 43.

By the way, if the first filter 14 and pressure detectors 16 and 17 are provided at the auxiliary filter 41, it is possible to measure the dry suit and SOF with one sampling pipe. However, if a small first filter 14 with high differential pressure sensitivity is provided at the auxiliary filter 41, the pressure in the cooling pipe 42 will be greatly reduced, and the flow rate will increase. This increases the differential pressure across the two filters 34. The tendency for this differential pressure to increase varies by about 20 to 30% from filter to filter, and cannot be sufficiently corrected by the calculators 19 and 39. Therefore, as in the above embodiment, two sampling pipes were provided to measure the dry suit and SOF separately. Note that when the filter diameter is increased by x times, the differential pressure sensitivity per deposition decreases to 1/x ⁴ .

In the above embodiment, the sampling gas was heated using the coil heaters 13 and 33, but instead of this,
Heating may be performed by wrapping a ribbon heater around the outer periphery of the sampling pipe, or heating may be performed using a burner or the like.

Moreover, when heating the sampling gas with a coil heater, a heat insulating material or the like may be provided on the outer diameter of the pipe.

Furthermore, as shown in FIG. 8, the pipe on the upstream side of the auxiliary filter 41 may be formed to have substantially the same outer diameter as the filter 41, and the coil heater 33 having a large diameter may be provided in this pipe.

It goes without saying that the control filter 53 and the capillary tube 54 may be any aperture elements, and are not limited to their shapes. Furthermore, one of these throttling elements can be omitted depending on the nature of pressure fluctuations within the dilution tunnel 5. For example, if the amount of variation in the DC component of the pressure variation can be ignored, the control filter 53 can be omitted.

Effects of the Invention As described above, according to the present invention, it is possible to measure dry suits and SOF in exhaust gas in real time, and the measurement can be performed with high precision.

[Brief explanation of drawings]

Fig. 1 shows an embodiment of the present invention, and Fig. 2 is a partial cross-sectional system diagram, and Fig. 2 is a sectional view showing an experimental apparatus for determining the relationship between the collected matter on the filter and the temperature in front of the filter. , Figure 3 is a graph showing the relationship between the collected matter on the filter and the temperature in front of the filter, Figure 4 is a graph showing the relationship between the amount of dry suit collection and filter pressure loss, and Figure 5 is the graph showing the amount of SOF collected. Fig. 6 is an equivalent electrical circuit diagram showing the operation of the control filter and capillary tube, Fig. 7 is a graph showing the relation between the pressure before and after the differential pressure converter, and Fig. 8 is a graph showing the relationship between pressure loss and filter pressure loss. FIG. 7 is a sectional view showing another embodiment of the pipe and coil heater on the upstream side of the auxiliary filter. 5... Dilution tunnel, 10... First sampling pipe, 11... First sampling pump, 1
3... Coil heater (first heating means), 14...
First filter, 18...First differential pressure converter, 30...
...Second sampling pipe, 31...Second sampling pump, 33...Coil heater (second heating means), 34...Second filter, 38...Second differential pressure converter, 41...Auxiliary filter, 52 ...Control filter (first aperture mechanism), 54... Capillary tube (first aperture mechanism), 63... Control filter (second aperture mechanism), 64...
Capillary tube (second aperture mechanism).

Claims (1)

[Claims] 1 After diluting and mixing the exhaust gas of the internal engine with a large amount of clean air in a dilution tunnel, the diluted mixed gas is guided to first and second detection means, and the first detection means detects the amount of dry suit in the exhaust gas. The second detection means detects soluble organic matter in exhaust gas, and the first detection means includes a first detection means for extracting a part of the diluted mixed gas from the dilution tunnel. a sampling pipe, a first sampling pump for flowing diluted mixed gas into the first sampling pipe, a first filter provided in the middle of the first sampling pipe to collect dry suit, and a first filter for collecting dry suit from the first filter. a first heating means provided upstream of the first sampling pipe; a first differential pressure converter that detects a pressure difference before and after the first filter;
a first throttling mechanism that suppresses the amount of fluctuation based on pressure fluctuations in the first sampling pipe, which is provided between the pressure extraction part on the upstream side of the first filter and the first differential pressure converter; a first calculation device that calculates the amount of dry suit in the exhaust gas based on the time differential value of the difference signal;
A second sampling pipe for taking out a portion of the diluted mixed gas from the dilution tunnel, a second sampling pump for flowing the diluted mixed gas into the second sampling pipe, and a second sampling pump provided in the middle of the second sampling pipe. a relatively large auxiliary filter for collecting dry suit; a second heating means provided upstream of the second sampling pipe from the auxiliary filter; and a second heating means provided downstream of the auxiliary filter for removing soluble organic matter. A second filter for collecting the air, a second differential pressure converter for detecting the pressure difference before and after the second filter, and a pressure outlet on the upstream side of the second filter and the second differential pressure converter. a second throttling mechanism installed in the second sampling pipe for suppressing the amount of fluctuation based on the pressure fluctuation in the second sampling pipe; and a second throttle mechanism for calculating the amount of soluble organic matter in the exhaust gas based on the time differential value of the pressure difference signal. 1. A vehicular particulate emission measuring device, comprising: a computing device.