ON THE STRUCTURE OF STEADY FLOW-THROUGH DUAL-INTAKE ENGINE PORTS

The influence of intake port design on the flow field in a dual-intake valve engine was investigated using computational fluid dynamics, in order to study the effect of inlet port design on the in-cylinder flow . A detailed 3D computational grid incorporating all the features of t he Ford Zetec production engine inlet ports, valves and cylinder head was initially created and the flow structure modelled at 5 and 10 mm v alve lifts under steady flow conditions. Comparisons of computational results with experimental data obtained by laser Doppler anemometry in dicate that the flow characteristics have been predicted well in most regions. Flow generated by different intake port designs was also simu lated by introducing air into the cylinder at different directions to the inlet valve axes and the effects of port deactivation, throttling and exhaust gas recirculation were examined. The implications of the r esults for intake port design are discussed.