The closed cycle diesel engine provides an economic solution to fill the strongly needed energy gap for naval submarine between the low performance conventional diesel electric system and the high performance nuclear reactor plant. The interrelationships between the non-air oxidants with moderate gases for synthetic atmosphere and engine performance, are either not well documented or understood. A theoretical model based on fuel/synthetic atmosphere cycle approximation for the diesel engine, is developed. Model results show direct reflection of the intake gas mixture constituents effects without the uncertainties associated with the combustion process for actual cycle modeling under synthetic atmosphere. This necessitates the generation of temperature entropy charts for both synthetic atmosphere and corresponding combustion gases. The charts and engine cycles presentation are progranuned for PC with sufficient generality to represent any synthetic atmosphere constituents and under different excess synthetic atmosphere factors.
An experimental rig, including single cylinder diesel engine, gas metering apparatus and instruments, is designed, constructed and employed to provide results for comparison. The performance deteriorating effects due to CO2 % increase by volume and the beneficial effects due to 02% increase by volume, in the engine inlet mixture, are analyzed. The theoretical model results, show satisfactory correlation with the experimental results and/or previous works.