An Investigation into Power Losses of Manual Transmission System Using Different Viscosity Oils

Abstract

In this study, experiments are carried out to investigate the influence of several operating conditions on the power losses and efficiency of an automotive manual transmission. With all the operating parameters controlled tightly, power losses are measured for different loaded and unloaded conditions in a five-speed manual transmission system. Various experimental studies have been conducted to see the influence of parameters such as input speed, load, oil temperature and oil volume on load-dependent and load–independent power losses of the transmission. The effect of viscosity on the power losses are found by using four different oils (75W90, 80W90, 20W50 and 85W140) having different viscosities (0.075, 0.0844, 0.0919 and 0.3399 Pa-s) in the gearbox. It is found that all these parameters play a very significant role in the transmission power losses. Other than oils, nanofluids are also used to check the power losses by dispersing alumina nanoparticles in gear oil (75W90). It is reported that power losses are not affected too much on addition of nanoparticles but the rise in temperature is minimized. In order to increase the overall transmission efficiency, several conclusions are drawn.