Gas Flow Velocity in Inlet Pipe, Exhaust Pipe and Cylinder of Two-Stroke Cycle Engine

Abstract

The velocities of the inlet air, the exhaust gas and the air flow in the cylinder of crankcase scavenged two-stroke cycle engines were measured successfully by the method utilizing the property of electric discharge. The test results are as follows: The inlet air velocity varies mainly due to the natural oscillation in the system consisting of inlet pipe and crankcase, and it is influenced by the compressibility of the air. It is also recognized that the maximum charge is obtained by making the port opening period equal to 3/4 of period of the natural oscillation. The velocities in the transfer passage and the exhaust pipe during the scavenging process are influenced by the oscillation system consisting of crankcase, transfer passage, cylinder and exhaust pipe and are also influenced remarkable by the air column oscillation in the exhaust pipe when the engine speed is high.