Abstract
In order to meet the accuracy requirements in the vehicle development process, it is essential to consider transient effects in the calculation of vehicle performance and fuel consumption. Besides trend prediction based on stationary input data, state-of-the-art simulation tools for special vehicle parts contain accurate models for the analysis of transient effects. The coupling of original independent simulation programs makes the simulation of transient effects of the entire system engine, drive train and vehicle possible. A decisive quality improvement of the performance calculation including dynamic power train states can be achieved by linking the programs AVL CRUISE (vehicle simulation) and AVL BOOST (engine cycle simulation). Furthermore, the coupling with the one-dimensional fluid flow code FLOWMASTER enables the consideration of transient thermal engine conditions by means of a thermal network using the lumped-capacity method. Templates of thermal networks of the engine structure with several discretization levels have been developed. The parameters of the network elements are determined a short list of key data.