Some Results of 3-d Combustion Simulation of the Z combustion System

The simulation was carried out in The Helsinki University of Technology in the Internal Combustion Engine Laboratory. The flow field of the combustion simulation has been received from a 3-d flow simulation of the engine.

The calculated combustion chamber geometry is a groove in the piston. The geometry was not optimized for these calculations.

The intake valves are designed to make supersonic flow possible. The valves work as nozzles and direct flow tangentially to the cylinder.

The results from the simulation:

	(10° BTDC) The situation just before fuel injection. The temperature difference comes from a pressure wave. The flow field has been got from a 3d-flow simulation program.
	(9° BTDC) The fuel injection has just begun.
	(7° BTDC) The fuel vaporizes before ignition.
	(5.4° BTDC)
	(3.2° ATDC)
	(9.7° ATDC)
	(14.8° ATDC) The fuel injection has been cut down just before the burned fuel/air has gone around the combustion chamber.
	(15.3° ATDC) As the piston goes down the view plane of the simulation moves over the combustion chamber.
	(18.4° ATDC)
	(22.9° ATDC)
	(25.9° ATDC)
	(30° ATDC) Situation at the end of the simulation.