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In this work, the design and testing of a silicon-nitride (Si3N4) piston-cup for a Petter AV1 laboratory diesel engine is presented. A preliminary design was first prepared and tested for thermal shock. The tests showed that non uniform displacements occurred between the ceramic plate and the piston. An improved design was then prepared, which allowed control of the characteristics of the gasket mounted between the ceramic plate and the piston. This second design was evaluated by thermal shock and exposure to cyclic pressure variation, followed by engine tests. A short description is given of the experimental set-up used for investigating the ceramic materials which are candidates for the moving parts exposed to thermal and dynamic shock in internal combustion engines. Finally two pistons with ceramic top plates were introduced in the engine with thermocouples mounted at different points of the liner and exhaust valve.

At present the market of Wankel engines is limited to some special applications. This fact explains absence of commercial software products specially developed for this engine simulation and prediction of its performance. Conversely, there are available and widely used software products for simulation of reciprocating-piston engines performance. Some attempts are known in using this software for prediction of Wankel engine performance. This paper details an approach used in these attempts. Main differences between both types of engines are summarized and principles of a virtual reciprocating-piston engine compilation are developed. A method of virtual blowing was developed for assessment of discharge coefficients for intake and exhaust ports. Comparison of simulation results with the measured performance of two UAV Wankel engines showed sufficient accuracy of the suggested approach.