Flow Investigation and Simulation of the Air Filter of a SI Engine

The filtering efficiency is affected directly by the pressure drop throughout. In this study, pressure drop and other flow parameters throw the air filter of Peugeot 405 is modeled, numerically. Flow is supposed to be incompressible and turbulent. The k-
turbulent model was used along with first-order upwind scheme for convective terms discretizations. The obtained results show the range of pressure drop between 0.05% and 1.9% depending on the engine speed. This amount of pressure drop is negligible in comparison to the pressure drop in other parts of air feed system. Therefore, one can increase the power of filtering. The numerical results indicate the presence of vortices in the edges of inlet section of filter hose. This vortices leads to decreasing of filtering efficiency. For eliminating the vortices, some changes have been made on the cross section of inlet pipe and its junctin to inlet box. Then the new geometry was analyzed. The results confirm the remove of vortices and a rather small reduction in pressure drop.