润滑油对NEDC工况变速器传动效率的影响分析

Analysis of the Influence of Lubricant on Transmission Efficiency of Transmission Under NEDC Operating Condition

变速器作为传动系关键的零部件之一,直接影响整车的NEDC油耗。为了提升某MPV车型的NEDC综合油耗,提出了一种基于NEDC工况的变速器效率测试方法,并利用该方法对比了不同润滑油的黏度、温度、添加剂等因素对变速箱传动效率的影响。试验表明,该测试方法能更准确地反映变速器NEDC工况下的综合效率;润滑油黏度相对越低,变速器的传动效率越高;油温升高引起的油膜厚度的减少对变速器效率的影响大于因转速升高引起的油膜厚度的增加对变速器效率的影响,且有利于提高变速器的传动效率;润滑油增黏剂有利于提升油品的黏温特性,且在一定温度范围内,随着温度的升高,润滑油黏温特性对于变速器传动效率的影响大于润滑油黏度对变速器传动效率的影响。

The transmission is a key part of the drive train,and it has a direct impact on the vehicle NEDC fuel consumption. In order to improve the NEDC integrated fuel consumption of a MPV model,a test method of transmission efficiency based on NEDC is proposed. The influence of different lubricating oil viscosity,temperature,additive and other factors on gearbox transmission efficiency is compared. The results show that the viscosity of lubricating oil is lower under NEDC,the transmission efficiency of transmission is higher.The decrease of the oil film thickness caused by the increase of oil temperature has greater influence on the transmission efficiency than that caused by the increase of the oil film thickness due to the increase of the rotation speed and the transmission efficiency of the transmission. The viscosity-temperature characteristic of lubricating oil viscosity enhances the viscosity-temperature characteristic of oil,The influence of transmission efficiency is greater than that of lubricating oil viscosity on transmission efficiency.