Small-scale rotary engine power system development status

The liquid fueled miniature Wankel engine project is directed toward the development of a practical small-scale power generator. This power generation system is based upon an engine that has a displacement of approximately 350mm and a designed power output of approximately 50W. Recently, the project has seen some encouraging results through design improvements in many of the system components, most notably sealing. Seal efficiency has improved from below 10% to 50%, comparable to commercially available engines. This improvement has resulted in naturally aspirated operation with high volumetric efficiency and operation on liquid fuels. These improvements have been confirmed by an increase in compression ratio and a commensurate increase in power output. In a product such as this, the unit cost is an important factor in its overall viability and the engine design reflect the need for reduced production cost to make the unit competitive with devices of similar power output. This work summarizes the development status of the program and indicates future directions with the expectation of a fully operational prototype system in place by the end of 2004.