Abstract：To develop particulate filter with high filtering efficiency, a comprehensive mathematical model of trap capture efficiency was established based on the capture theory of packed bed, and the established model was validated by Matlab. The results show that in the whole process of particulate trapping, Brownian diffusion plays a dominant role. The reduced exhaust flow rate and the improved exhaust temperature can improve the diffusion coefficient and the capture Brownian integrated capture coefficiency, while the exhaust flow rate and the exhaust temperature have slight effect on the straight intercept capture mechanism. When the particle size is less than 100 nm, the integrated capture coefficient increases rapidly with the decreasing of particle size， and the number has little difference with the Brownian diffusion coefficient. When particle size is greater than 100 nm, the straight intercept capture mechanism is enhanced, and the comprehensive capture coefficient decreases slowly with the increasing of particle size. When the particle size is from 100 nm to 500 nm, the capture mechanisms compete each other to obtain the minimum value of comprehensive capture coefficient.
2016, Vol. 37 
