Search Results

The incorporation of a detailed engine process calculation that takes into account thermal behavior of the engine and exhaust system is essential for a realistic simulation of transient vehicle operation. This is the only possible way to have a precise preliminary calculation of fuel consumption and emissions. Therefore, a comprehensive thermal network of the engine based on the lumped capacity method has been developed. The model allows the computation of component temperatures in steady state operation as well as in transient engine studies, e.g. investigations of engine warm-up. The model is integrated in a co-simulation environment consisting of a detailed vehicle and engine cycle simulation code. The paper describes the procedure of the co-simulation and presents several examples of warm-up simulations.

Due to its high number of free parameters, the new generation of gasoline engines with direct injection require an efficient calibration process to handle the system complexity and to avoid a dramatic increase in calibration costs. This paper presents a concept of specific toolboxes within a standardized and automated calibration environment, supporting the complexity of GDI engines and establishing standard procedures for distributed development. The basic idea is the combination of a new and more efficient online DoE approach with the automatic and adaptive identification of the region of interest in the high dimensional parameter space. This guarantees efficient experimental designs even for highly non-linear systems with often irregularly shaped valid regions. As the main advantage for the calibration engineer, the new approach requires almost no pre-investigations and no specific statistical knowledge.