Abstract
A method for industrial application of an engine run-up simulation is presented. The method is demonstrated for the new Audi V8 4,2 liter Otto engine. The run-up simulation is performed for the whole operating range of engine speeds. The analysis procedure bases on a modal frequency response solution for small steps of increasing engine speeds. To facilitate the update of the excitation data, the excitation is formulated in terms of power spectra and cross spectra. Local damping is introduced for the most important damping mechanisms of the engine, i.e. for joints, different materials and surfaces with fluid contact. This leads to a high quality of the simulated response and an information density which can be directly compared to Campbell diagrams of measured run-ups.