Simulation Study on the Effect of Uneven Fuel Injection of Each Hole on the Combustion Process of Ethanol-Diesel Blend Fuel

Abstract

The small diesel generator has been widely used. When compared with vehicle diesel engine, it has stable working speed, small load variation range and lower requirements for fuel performance, so the fuel ethanol can be more easily applied for the diesel generator. The blend fuel containing 5% ethanol and 95% diesel (E5D95) is tested on a generator powered by F186. A 3D combustion model based on the injection position and angle of each hole of the diesel engine is established and verified by using the test data. Based on the measured injection rate of each hole of the 4-hole diesel injector, the even injection rate of each hole and the measured uneven injection rate of each hole are made as the injection settings for the combustion simulation. The effect of the uneven injection rate of each hole on the combustion process of ethanol-diesel blend fuel is comparatively analyzed. Due to the uneven injection of each hole, the ignition starting point is moved forwards, the maximum pressure and temperature in the cylinder are higher, NO generation is larger, soot generation is slightly smaller, and the emission of HC and CO is higher.