A Finite-Difference Approach for Solving the Gas Dynamics in an Engine Exhaust

Abstract

Finite-difference schemes have been considered for solving the unsteady, compressible gas flow in the exhaust pipe of a turbocharged diesel engine. The most promising scheme, based on centred differencing, was developed to incorporate the boundary conditions applicable to the exhaust problem. Good comparisons were obtained with results for pipe pressure from characteristics programmes at intermediate and final stages of the development. Recommendations are made for reducing the computation time of the centred-difference programme.

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