The Influence Research Of Engine Performance For5W30/5W20Oil Characteristics

In order to help the customers choose the appropriate engine lubricating oil, basing on the actual car driving conditions the effects of using different lubricating oil on engine performance were studied.In this paper, after analyzing the engine lubrication system and the engine oil classification, the physical characteristics of5W30,5W20were studied. Then analyzed the effects on engine lubrication (oil pressure, oil flow rate) of5W30,5W20by using both simulation and empirical formula calculate.The study contents and results of this paper include:(1) Analyzed the engine lubricating oil(including viscosity, viscosity-temperature characteristics, and density), found that at a certain working temperature engine lubricating oil viscosity has a great influence on the engine lubrication system.(2)Analyzed the physical and chemical characteristics of the commonly used engine lubricating oil (5W30,5W20) in the current market, found that the viscosity of5W30is greater than5W20’s in the temperature range20℃to180℃, the viscosity-temperature characteristics of5W30is greater than5W20’s in the temperature range-30℃to120℃, the density of5W30is greater than5W20’s in the temperature range40℃to160℃.(3) Created one gasoline engine lubrication system model using Flowmaster, then calibrated the pressure and the flow rate of the lubrication system, the error was acceptable and reached calculation requirement.(4) Calculated the different lubricating oil’s(5W30and5W20) effects on engine performance by using the lubrication model in Flowmaster. Then found that compared to5W30using5W20could enlarge the flow rate by4.1%on average, the pressure of the main gallery decrease by3%on average, and the power consumption of oil pump could decrease by3.05%on average. Using5W20is beneficial to the engine performance.(5)Calculated the oil flow rate of the engine lubricating parts(main bearing, connecting rod bearing, camshaft bearing) using empirical formula. Then compared5W30and5W20, found that both the oil could reach the flow rate requirement. In conclusion, found that choosing appropriate engine lubricating oil according to the different places could not only reach the engine lubrication requirement but also reduce the power consumption and enhance the engine efficiency.