Study of the influence of methanol/F-T diesel combustion particle materiality parameters on the deposition process in diesel particulate filter trap units

Abstract

The use of different fuels will change the structural characteristics of the diesel engine exhaust particulates. This paper studies the impact of the particle physical and structural properties on DPF capture, and proposes to measure the particle deposition by particle chain length and particle layer thickness. This study builds a test bench based on a four-cylinder diesel engine, using F-T diesel fuel with 0%, 5%, and 15% methanol mixing ratio to collect particles after running for half an hour under the calibration condition. The physical properties of particles were analyzed by synchrotron radiation small angle scattering. The particle formation rate, friction between particles, particle size, and other parameters of mixed fuel combustion particles were then confirmed. The particle model was developed in EDEM based on the experimental data, and the creation of particle chains was studied. In addition, the impact of collision bounce on the particle deposition was taken into consideration to mimic the process of particle collision deposition on the filter wall. The results show that when the methanol mixing ratio increases, the Particles Number (PN) value of methanol F-T diesel combustion particles increases, the inter-particle friction increases, and the average particle size decreases. During the deposition process, the amount of deposition on the non-windward side of the DPF trap unit sharply increases, and the particle deposition efficiency increases with the increase of the deposition time. The particle deposition increases with the deposition time, and the thickness and length of the particle layer and chain increase with the increase of the particle number, friction, and size.