Semin : An Investigation of Valve Lift Effect on Air Flow and CD of Four Stroke Engines Based on Experiment
The coefficient of discharge (CD) is defined as the ratio of actual discharge to idealdischarge. In an engine environment, ideal discharge considers an ideal gas and the process to be freefrom friction, surface tension, etc. Coefficients of discharge are widely used to monitor the flowefficiency through various engine components and are quite useful in improving the performance ofthese components. The flow through engines it is equally important to have accurate values forcoefficients of discharge through the combinations of valves, ports and ducts. In this experimentinvestigation of air flow and coefficient of discharge are desirable for inflow (reverse flow) through theexhaust port using SuperFlow Flowbench. The coefficients of discharge the diesel engines can be quitemeasured under steady flow conditions for a range of pressures and flows. This paper presentsexperimental results for air flow and coefficient of discharge investigating the intake and exhaust flowof four stroke direct injection diesel engines. The CD measurements are shown for various pressures,valve lift per diameters (L/D) ratio conditions at the intake port pipe to cylinder and cylinder to exhaustport pipe geometries.