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The theoretical analysis and experimental results of tests on burning of deeply stratified charge in the bi-modal combustion chamber is presented. Tests were performed in a constant volume modeling chamber and in a car's engine. Constant volume combustion modeling allows evaluating optimum parameters for effective combustion of deeply stratified charge in the bi-modal combustion chamber. Theoretical calculations of the variation of some thermodynamical parameters under engine conditions for the homogenous and stratified charge are presented, showing adventures of stratified charge combustion. Investigation shows that elaborated method of organization of the combustion process of the stratified charge allows essential improving the technical, economical and ecological performances of the engine.

The performance of classical spark ignition system and PJC ignition system developed by A.K. Oppenheim, has been tested in IC piston engine operating at full and partial load. Tests were conducted in the four stroke two cylinder engine. Differences in efficiency and emission for both ignition systems were tested for the power range from half load to full load. It was found that with the PJC system the engine operates more economically at the partial load and emission of hydrocarbons and CO was decreased at partial load. This was basically due to improvement of lean mixture combustion. However, the emission of NO was always higher for PJC than for conventional spark ignition.

Research of combustion process was made in a specially designed research engine in which simultaneous pressure measurement and Schlieren visualization of the combustion process were possible. Pressure as well as the timing of each picture was recorded by the data acquisition computer system. The whole operation of the experimental apparatus is also controlled by PC computer connected to a special control unit. Combustion studies were focused on the comparison of classical spark ignition system to the jet ignition, initiated by a specially produced Pulsed Jet Combustion (PJC). Comparison of the flame propagation velocity and variation of the pressure in the chamber for different ignition systems and different equivalence ratio of combustible mixtures were made. It was found that under all experimental conditions jet ignition is superior over conventional spark ignition system. Comparison of pollutants emission was also made.

A comprehensive multizone zero-dimensional diagnostic model is presented for a spark ignition engine cycle. It considers the charge to be made up of two zones, burnt products and unburnt reactants, both under the same, time varying pressure. For each crank angle increment during combustion, a new distinct zone of burnt products is created. It does not exchange mass and heat with the rest of the charge and undergoes a series of continuously varying, yet distinctly different thermochernical processes. The model computes the rate of heat release and other thermochemical properties of all the zones from measured pressure crank angle data obtained from an instrumented engine. A thermochemical sub-model which predicts the properties of the unburnt and burnt gases during the combustion and expansion, as well as the chemical energy release during exothermic process, was developed.