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The target for future cooling systems is to control the fluid temperatures and flows through a demand oriented control of the engine cooling to minimize energy demand and to achieve comfort, emissions, or service life advantages. The scope of this work is to create a complete engine thermal model (including both cooling and lubrication circuits) able to reproduce engine warm up along the New European Driving Cycle in order to assess the impact of different thermal management concepts on fuel consumption. The engine cylinder structure was modeled through a finite element representation of cylinder liner, piston and head in order to simulate the cylinder heat exchange to coolant or oil flow circuits and to predict heat distribution during transient conditions. Heat exchanges with other components (EGR cooler, turbo cooler, oil cooler) were also taken into account.

The predictive capabilities of an innovative multizone combustion model DIPulse, developed by Gamma Technologies, were assessed in this work for a last generation common rail automotive diesel engine. A detailed validation process, based on an extensive experimental data set, was carried out concerning the predicted heat release rate, the in-cylinder pressure trace, as well as NOx and soot emissions for several operating points including both part load and full load points. After a preliminary calibration of the model, the combustion model parameters were then optimized through a Latin Hypercube Design of Experiment (DoE), with the aim of minimizing the RMS error between the predicted and experimental burn rate of several engine operating points, thus achieving a satisfactory agreement between simulation and experimental engine combustion and emissions parameters.

In the automotive industry, CAE methods are now widely used to predict several functional characteristics and to develop designs that are first-time-capable to meet programs targets. The N&V area is one of the increasing key factors for a product differentiation; costumers expect not only more powerful and more fuel efficient but also less noisy engines. The oil pan is one of the bigger contributors to engine radiated noise and to diesel knocking, so that great attention is paid within GM to optimize oil pans of Diesel engines by following a CAE-based approach to achieve a “first-time-capable” design for this component. This allows focusing the subsequent N&V testing activities to pinpoint modifications mainly on those components with shorter lead time. This paper describes the key-steps that are executed to optimize the oil pan design by using CAE methods with the main intent of reducing its noise radiation.