1D and 3D Modeling of Modern Automotive Exhaust Manifold

Abstract

This paper presents the simulation of the multi-cylinder 4-stroke cycle spark-ignition engine using a commercial simulation tool, AVL BOOST and Fire. Various models were examined to select the appropriate models that would best serve to analyze the main components of the exhaust systems: the plenum chamber, the muffler and the exhaust manifold branch junction. For the plenum chamber and the muffler, the whole duct model was tested. In order to analyze the exhaust manifold branch junction, a complicated model which reflects the actual shape and involves pressure drops, velocity magnitude and sound pressure was compared to a simplified one. However, the results from 1D and 3D model calculations compared with Honda K20B Engine experimental data also show that both models are applicable with satisfying accuracy for exhaust manifold branch junction. The simplified 1D model is recommended in regard to convenience in modeling and efficiency in calculation.