Influence of Intake Valve Lift on Flow Capacity of Intake Port 2019-01-0223
A three-dimensional model of a diesel engine intake port was created and the model was validated. The modeling method was validated from three aspects of mass flow, velocity field and pressure field by steady-flow test, PIV velocity field test and pressure field test. The actual model created based on the modeling method was validated by the steady-flow test. Based on this model, the influence of intake valve lift on the flow capacity of intake port was studied. The results show that, under different intake pressure and relative pressure difference, the discharge coefficient increases first and then converges with the increase of valve lift. Under the same valve lift condition, the discharge coefficient is almost the same at the same relative pressure difference and different intake pressure. Meanwhile, the discharge coefficient decreases slightly with the increase of relative pressure difference at subsonic velocity condition, and decreases sharply after supersonic velocity condition, but the mass flow is still increasing slightly. The optimum ratio of valve lift and valve seat diameter is related to the relative pressure difference, it increases first and then converges to 0.34 with the increase of relative pressure difference.
Yang Xu, Fushui Liu, Yang Hua, Jingmin Rui, Yikai Li
Beijing Institute of Technology, Beijing Polytechnic