흡기계내 역류현상에 대한 해석

Abstract

Reverse flow, where the flowrate is measured, should be avoided to measure the incoming air flowrate to cylinder with a flowmeter which cannot distinguish the direction of the flow. Furthermore, the intake flow in single-cylinder engine test is needed to simulate the realistic flow in the multi-cylinder engines. In this paper, the minimum volume of surge tank to be installed in front of intake manifold for the experiments of single cylinder, is obtained. And, the different origins of reverse flow, are identified for single- and multi-cylinder engine. In the case of single cylinder engine, the volume of surge tank played the dominant role to prehibit reverse flow. Under the condition of 1000 RPM fill load, about 500-1000 times the volume of displacement volume of a cylinder is required to settle it down. For multi-cylinder engine, as the engine speed decreases and the load increases, the reversing flow is apt to occur, and the frequency of intake stroke of cylinders was the major factor which determines the occurance of reversing flow.