Research On Simulation Of Dimethyl Ether (DME) Engine Based On GT-Power

The development of China's automobile industry is facing dual pressure on energy supply and environmental protection. To develop of new clean energy, specially in line with the characteristics of energy resources in China is urgent. Dimethyl ether (DME) is a new, clean alternative fuel of diesel. As the special physical and chemical characteristics of dimethyl ether, it can achieve high efficiency and low-pollution combustion, and also can improve China's structure of energy.DME is paid more and more attention in recent years. Using engine burning DME on the city buses is beneficial not only to saitisfy the bus characteristics of stop-need and good low-speed torque, but also can achieve a clean and Soot-zero combustion. Prospects of Dimethyl ether (DME) is becoming clear, but the technology is not mature yet. The current DME in a diesel engine is still in the promotion of applied research and experimental. Studying the combustion characteristics of dimethyl ether by using numerical simulation method for performance simulation can predict performance of combustion engines well, be instead of part of the engine test, shorten the development cycle, save funds for the development and give guidance on optimization of DME engine.In this paper, simulation software of GT-Power created a engine simulation model burning DME. Added the dimethyl ether (DME) fuel depot in the software, improved the original engine's fuel supply and injection system model according to the special physical and chemical properties of DME,the article build a simulation andanalysis platform of dimethyl ether engine. By Using the platform, the article analyzed the parameters of engine including fuel injection timing, nozzle number and diameter of the engine, including technical,and also analyzed the effects on the engine performance of power and emission when methanol components in dimethyl ether is different.The research found that improved the parameters of engine fuel supply and injection system,comparing the diesel, the engine fueled with dimethyl ether, the low-speed torque is similar, but the middle-speed at high-speed torque is about 30% higher, power increase about 20%; fueled with dimethyl ether the maximum broke out pressure, maximum pressure rise rate is lower than diesel, the same time, NOX emissions decreased significantly, more than 35% decline, HC emissions decreased, but CO emissions increased slightly, particularly dimethyl ether engine operating condition in all the soot emissions is zero. In addition, the DME fuel content of methanol in fuel consumption and NOX emissions have some impact. Comparing 5% methanol content 20% methanol content of the fuel has consumption increased by about 10%, while NOX emissions decreased by about 15%. The results show that the engine fueled with dimethyl ether could reach the standard of the original machine in the power performance. And for the main pollutants for the diesel engine NOX and soot the engine fueled with dimethyl ether decreased significantly, compared with the original machine. Therefore, it has a wide application prospect to research and develop of DME engine, simulation platform building in this paper for DME engine has an important role on development rapid of the DME engine.