| High attention is paid to the research on the problem of diesel particles emission at home and abroad, but diesel particle reentraiment in exhaust pipe and the influence factors what we know are very limited. As one of the important phenomena in controlling of the diesel engine's particles and paticle sampled, analysing particle reentrainment's influence factors, regulary and summarising the way of controllong particle reentrainment become very meanful.According to contact radius and werkstoffart, analysing and choosing contact models, the DMT model was chosed as the foundation of aggregate reentrainment model. On that base, analsing reentrainment mechanism models, present the model to clarify the reentrainment mechanism of spherical aggregates. Then, present the model to clarify the reentrainment mechanism of ellipsoidal aggregates, basing on the model of spherical aggregates and configuration of ellipsoidal aggregates. Especially, derive the expression of drag force to consummate the model.The reentrainment of spherical and ellipsoidal deposited aggreagets in turbulent aerosol flow has been studied theoretically. The forces, i.e., gravitational force, adhesive force, collision force, aerodynamic drag force and lift force, especially the forces change with aggregate figuration are studied. The moment of forces, i.e., gravity, particle adhesion, aerosol collision and aerodynamic drag, especially the moment of forces change with aggregate figuration are studied. Then, analsing the adhesion angle, the tube diameter and the average flow velocity acting on aggregates, the relationship between the moment of forces and the figuration of aggregate, and the way of motion status changing with the moment of forces.In this paper, analyse the forces and the moment of forces changing regularity, the way of controlling particle reentrainment. Theoretical basis and research foundation of diesel particle reentrainment regularity in turbulent pipe exhaust system are supplied by the research results.
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