A kind of device that can detect particulate filter filtration efficiency and pressure drop
Technical field
The utility model relates to a kind of device that can detect particulate filter filtration efficiency and pressure drop, test diesel engine condition (power, rotating speed, accelerator open degree etc.) is mainly mapped to (extraction flow, temperature, mix ingredients etc.) in exhaust conditions by it, identify the thing of wherein general character, complete the detection to particulate filter filtration efficiency and pressure drop.
Background technology
In exhaust gas from diesel vehicle, the discharge of particle is tens times of gasoline car, and particle seriously contaminated environment harm humans is healthy.Particulate filter controls diesel vehicle the most effective granular material discharged aftertreatment purification plant, and along with the harshness day by day of Abgasgesetz, the emission limit of various pollutant is more and more lower, and this just requires that the detection method of after-treatment device constantly carries out Improvement and perfection.The method that traditional detection particulate filter filtration efficiency and pressure drop use is Full flow dilution sampling, exhaust gas from diesel vehicle is all introduced dilution tunnel, mix with clean air for making tail gas, and the temperature of mixed gas is dropped to less than 50 DEG C, blower fan is caused to be difficult to the air inflow of control system, and space shared by pick-up unit is large, the price of equipment set and use cost are also very high.
Summary of the invention
In order to solve the problem, the utility model inserts stopple coupon in gas outlet, the mixed gas in diesel exhaust gas is carried out sampling and detects, thus save the space shared by equipment on the basis keeping original function.
The technical scheme that the invention for solving the technical problem adopts is: the two ends of mercury differential manometer are connected with outlet downstream with the inlet upstream of particulate filter, stopple coupon is inserted in gas outlet, distribute a part of gas, hydrocooler, pressure vacuum gauge and thermometer are installed before spinner-type flowmeter.Under the effect of vacuum pump, diesel engine vent gas is extracted out from the gas outlet of device through stopple coupon, and when flowing through particle collector, the particle in tail gas is trapped by filter paper.With the flow of sample gas in spinner survey system.Owing to containing water vapor in sample gas, for preventing water vapor from condensing in spinner-type flowmeter, before spinner-type flowmeter, install hydrocooler additional.With the pressure and temperature in pressure vacuum gauge and thermometer measure sample gas, under making that the reading of spinner-type flowmeter is transformed into the status of criterion.The voltage drop value between particulate filter inlet upstream and outlet downstream is measured with mercury differential manometer.With the particle that filter box absorbing particles filtrator does not trap.
The utility model has the advantages that, shared space is little, quality is light, low price, solve that Full flow dilution sampler volume is large, cost is high, by shortcomings such as space constraint.Meanwhile, its handiness, can be applicable to the diesel engine of various discharge capacity, and keeps good correlativity between energy and traditional pick-up unit.
Accompanying drawing explanation
Fig. 1 is a kind of front view that can detect particulate filter filtration efficiency and pressure drop device
1. particulate filters in figure, 2. mercury differential manometer, 3. gas outlet, 4. stopple coupon, 5. particle collector (inner clip glass fiber filter paper), 6. hydrocooler, 7. pressure vacuum gauge, 8. thermometer, 9. spinner-type flowmeter, 10. vacuum pump, 11. filter boxs
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described in further detail:
As shown in Figure 1, can detect a device for particulate filter filtration efficiency and pressure drop, it is made up of particulate filter (1), mercury differential manometer (2), gas outlet (3), stopple coupon (4), particle collector (5), hydrocooler (6), pressure vacuum gauge (7), thermometer (8), spinner-type flowmeter (9).The two ends of mercury differential manometer (2) are connected with outlet downstream with the inlet upstream of particulate filter (1), stopple coupon (4) is inserted in gas outlet (3), installs hydrocooler (6), pressure vacuum gauge (7) and thermometer (8) before spinner-type flowmeter (9).Vacuum pump (10) is utilized to serve as the power of mixed gas sampling, by combination gas from gas outlet (3) sucking-off through stopple coupon (4), when sample air-flow through particle collector (5) time, because inside accompanies glass fiber filter paper, the most of particle in sample gas can by Filter paper filtering.Under the effect of hydrocooler (6), the water vapor cooling in sample gas, prevents water vapor condensation in spinner-type flowmeter (9).Measure the pressure and temperature of sample gas with pressure vacuum gauge (7) and thermometer (8), convert the reading of spinner-type flowmeter (9) to the status of criterion, and record the time of sample gas by spinner-type flowmeter (9).Meanwhile, the difference in height of particulate filter (1) inlet upstream and outlet downstream mercury differential manometer (2) is measured, to be converted into the voltage drop value of particulate filter (1).The particle do not trapped is absorbed with filter box (11).
After off-test, weigh the particle mass on filter paper in particle collector (5), measure the sample gas volume through spinner-type flowmeter (9), calculate the mass concentration of exhaust gas particulate.Use the same method the mass concentration calculating respectively and install particulate filter (1) front and rear row gas particles additional, can draw the filtration efficiency of particulate filter (1).Do several groups of tests more, calculate the weighted mean value of particulate filter (1) filtration efficiency, and draw out the curvilinear motion relation of pressure drop extraction flow.