Simulation and experimental research on oil flow loss of diesel engine at plateau

For low oil pressure in diesel engine at plateau, the lubrication system of the diesel engine is researched through experimental test, theoretical analysis and CFD simulation. The results show that the ambient pressure affects the basic pressure in the whole oil passage. The inlet pressure of the oil pump equivalently decreases with the increase in altitude, resulting in lower ambient pressure. In this condition, asuction appears in the pump, which may reduce the main oil pressure significantly. As the flow rate keeps constant, the pipe flow loss decreases gradually with the increase in pipe diameter. Though the flow loss rate becomes smaller, the right angle junction has great influence on the flow loss, and for r/R≥1.5, the change of flow loss tends to be stabile. The plateau test results show that the engine oil pressure of the improved scheme is increased by about 30% at low rotating speed, and the oil pressure is increased by more than 50% at medium and high rotating speeds.