Geometric Parameters Influencing Flow in an Axisymmetric IC Engine Inlet Port Assembly: Part II—Parametric Variation of Valve Geometry

The influence of inlet valve geometry on IC engine port flow characteristics was investigated systematically by varying the key valve geometric parameters of fillet radius, cone angle, and seat angle. The analysis of flow through the port was measured for 36 valves having geometries determined by $R/D=0.20-0.30,$ cone angle 0–20 deg and seat angle 30–45 deg. Discharge coefficients were measured to gain an understanding of the general flow performance. These were used in conjunction with heat transfer data to gain a clear understanding of the state of the boundary layer on the valve and port seats for varying lifts and pressure drops. This established the presence or otherwise of the four flow regimes within the valve passage. The results demonstrate that the cone and seat angle have major effects on valve flow performance and enable engine designers to choose more readily the valve characteristics they desire. [S0098-2202(00)00404-1]