Three-dimensional computer analysis of flow and combustion in automotive internal combustion engines

The paper presents a method for calculating the three-dimensional flow-fields in reciprocating internal combustion engines, as a function of space and time, throughout the complete four-stroke cycle. The method is based on a computational procedure which solves the governing elliptic partial-differential equations on a finite-difference grid which expands and contracts with the motion of the piston, using a fully-implicit, iterative, finite-difference scheme. Results are presented for typical engines, under engine-motoring and spark-ignited conditions. It is concluded that careful physical experiments should now be conducted in parallel with the computer experiments to validate the predictions, before the model can be used directly in assisting engine design; but also that it is now practical, for the first time, to perform fully three-dimensional calculations of the flow within the engine.