Abstract
The unstable operation of the engine is found, when the pressue in the injection pipe of the DME(CH3OCH3) engine is lower than the saturation pressure of DME. This fact means that the flow of DME is choked by the bubbles which are generated by the cavitations and the injection rate of DME to the combustion chamber is too small to run the engine smoothly. In order to prevent the unstable operation of the engine, the pressure of DME in the injection pipe is always over its saturation pressure. The flow generated by the rapid moement of the solenoid valve simulates the injection system of DME fueled diesel engine. Experimental results conducted that the instantaneous pressure in the pipe depends on the wave propagation and the vibration of solenoid valve. The measured pressure in the pipe agrees with the calculated value by the one-dimensional unsteady DME flow model.
