Effect of the injection pressure on the internal flow characteristics for diethyl and dimethyl ether and diesel fuel injectors

Abstract

The spray characteristics of the diesel fuel are greatly affected by the cavitation formed inside the injector due to the high pressure differential across the nozzle. Many researchers are exploring the potential of using diethyl ether and dimethyl ether as an alternate for diesel fuel to meet the strict emission norms. Due to the variation in the fuel properties the internal flow characteristics in injectors for ether fuels are expected to be different from that of the diesel fuel. In this paper the numerical investigation is used to study and compare the internal flow cha-racteristics of diethyl ether, dimethyl ether and diesel fuel. The two phase flow model considering the fuel as a mixture of liquid and vapor is adopted for the si-mulation study. The injection pressure is varied from 100 bar to 400 bar and the flow characteristics of all three fuels are simulated and compared. Results indi-cate that all three fuels have distinct cavitating patterns owing to different prop-erty values. The dimethyl ether is found to be more cavitating than diesel and die-thyl ether fuels as expected. The mass of fuel injected are found to be decreasing for the ether fuels when compared with diesel fuel at all injection pressures.