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Open clutch spin loss computation is of interest for new clutch designs. It is desirable to minimize open clutch spin loss. Spin loss in automatic transmission clutches is mainly due to the viscous shear of the transmission fluid. Depending on the relative rotational speed of the plates the spin loss varies. At low rotational speeds the gap between the plates is filled with ATF (Automatic Transmission Fluid) and spin loss increases linearly with the rotational speed. At higher speeds the ATF layer, which is held together primarily by surface tension, begins to breakdown due to higher centrifugal forces and air pockets form at outward radial locations of the clutch plates. This results in a decrease in spin loss for the open clutch. CFD (computational fluid dynamics) modeling is an attractive option in calculating the spin loss for an open clutch.

It has been found during the transmission level test that oil pan is a major contributor of noise to the overall noise emanating from transmission. Oil pan being thin and having substantial surface area becomes a significant noise source. Keeping this in view it is very important to study the acoustic behavior of the oil pan. Several computational techniques are available to study the noise characteristics of such structures. Indirect techniques that compute normalized velocity distributions on the surface from frequency response analysis give a quick assessment of sound power of the structure but can't give the Sound Pressure Level (SPL) at microphone locations. Technique such as Boundary Element Method (BEM) can calculate the SPL but are computationally intensive as the size of the model increases. Infinite Element techniques overcome these shortcomings from the way they are formulated.