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An array of engine bearing analysis methods has been developed at General Motors over the years. All of these analyses consider wedge and squeeze effects, finite-length bearing, variation of load with crank angle, and cavitation effects. The simplest among them utilizes the so-called mobility method for solving the governing Reynolds equation. Others include finite-element solution for bearings with arbitrary geometry and grooving, finite-element solution for elastohydrodynamic lubrication, mass-conserving finite-volume solution, non-Newtonian lubricant analysis, and thermohydrodynamic analysis. This paper reviews these methods, describes when and how these methods are used, compares results and describes some applications.

A method for determining the optimum location of oil-feed holes in crankshaft journals is described. The method is applied to the 92 series Detroit Diesel Allison Division (DDAD) engines. On an average, the minimum oil-film thickness of the main bearings was increased 83% by relocating the oil holes. A qualitative verification of the results was obtained by a coolant-contamination test. The revised crankshaft was used in the MY1985 production of the engine.