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During a vehicle drive cycle, the oil in the engine oil pan sloshes very vigorously due to the acceleration of the vehicle. This can cause the pickup tube in the engine oil pan to become uncovered from oil and exposed to air, which affects the lubrication pump performance. Engine oil pan sloshing is inherently a 3D problem as the free oil surface is constantly changing. Multi-dimensional Computational Fluid Dynamics (CFD) methods are very useful to simulate such problems with high detail and accuracy but are computationally very expensive. Part of the engine lubrication system, such as the pump, can be modelled in 1D which can predict accurate results at relatively high computational speeds. By utilizing the advantages of both 1D and 3D CFD models, a coupled 1D-3D simulation approach has been developed to capture the detailed oil sloshing phenomenon in SimericsMP+ and the system level simulation is conducted in GT-SUITE where 3D spatial data is not required.

A multi-purpose valvetrain analysis tool has been developed, which is aimed at addressing all design issues arising in various stages of valvetrain development. Its capabilities include polynomial cam design, valvetrain mechanism kinematics, quasi-dynamic analysis, spring design/selection, multi-body elastic analysis of a single valvetrain with cam-follower and bearing tribology, and multi-valvetrain dynamics with camshaft torsional vibrations. The basic architecture of this tool is object-oriented. Its underlying basis is a library of cam design methods, kinematics operators, and dynamics/hydraulics/tribology primitives (masses, dampers, springs, etc.). On top of this basic system lies a higher-level library of valvetrain compound objects, which are pre-programmed sub-assemblies of valvetrain components built from the primitives. These high level objects minimize modeling effort and may be mixed with primitives, allowing construction of models for virtually any valvetrain.