Development of a rapid compression-expansion machine simulating diesel combustion

Abstract

A rapid compression-expansion machine machine was developed, which can simulate intake, compression, expansion and exhaust strokes in a single Diesel cycle by an electrically controlled and hydraulically actuated driving system. The machine features, (1) accurate control of piston position at TDC, (2) no effect of lubricant on HC emission due to the use of dry piston rings, (3) independent control of wall temperatures, and (4) high power output. The single-cycle operation permits Diesel combustion experiments under a wide range of operating conditions, easy access of optical diagnostics, and minimal amount of test fuel. The performance test showed that the machine can drive a D.I. Diesel piston with a 100 mm bore at a maximum frequency of 16.7 Hz at a maximum compression pressure of 15 MPa.