Design and Analysis of Engine Lubrication Systems

Methods for the design and analysis of engine lubrication systems have been developed and illustrated in a case study - a four cylinder high speed direct injection (HSDI) diesel engine for passenger car applications. The paper gives design methods and strategies for pump sizing and flow balance, including allowance for the worn engine applicable to a variety of engine classes. In addition the paper gives mathematical models for oil flows through piston cooling jets and plain journal bearings - fully grooved, partially grooved and plain bearings with a single oil hole feed. Methods presented can be used to design lubrication systems for optimum and practical specification of oil pump size, pressure relief valves, by-pass filtration, gallery sizes, oil flow through bearings in the cylinder head and cylinder block and piston cooling jets as well as calculating parasitic losses in the engine due to hydrodynamic pumping.