Wet clutches in heavy duty equipment
Wet clutches are widely used in automatic transmissions and limited slip differentials in vehicles today. In automatic transmissions they are used to transfer the torque from the driving engine to the drive train.
A wet clutch consists of one or more friction plates attached to one axle. Each friction plate is situated between two separator plates connected to the second axle which come in contact with the friction plate when the clutch is engaged. The clutch is engaged by putting pressure on the clutch forcing the friction plates and separator plates in contact causing the frictional forces to transfer the torque from the first to the second axle. The friction plates are a composite structure with a friction lining made from some "friction material" attached to a steel core. The clutch is called a wet clutch because it is immersed in a fluid. This fluid is usually an oil enriched with different kinds of additives to obtain desired frictional properties.
My work is focused on such clutches that are operating in heavy duty equipment such as wheel-loaders. In these vehicles the torque transfer is much higher than in the clutches of a passenger car. This results in different wear and torque transfer behaviour than we see in the car application. Another important issue is the energy losses that occurs in the clutch. If these can be reduced a lot will be won in terms of fuel economy.
It is desirable to find a way of dimensioning a cluch in such a way that it is optimized for use in a heavy duty vehicle with regards to the parameters mentioned above and this is one of the goals of this research.