The Development of a Stratified Charge Rotary Engine Apex Seal Material

The rotary engine has evolved into an alternate power source, along with the reciprocating engine and is finding many applications including automotive, industrial, and military. Recent advances in rotary engine technology include development of stratified charge engines with multifuel capability. These engines operate at higher peak pressures than the homogeneous charge type and require higher component mechanical strength properties and improved wear resistance for the sliding surfaces. The apex seal makes line contact with the rotor housing surface and, more than any other seal in the engine, is subjected to high contact loads and sliding surface temperatures which make it susceptible to high rate of wear. Combustion chamber pressure tightness, and thus engine performance, depend to a great extent on the apex seal wear. This requires that the phenomena associated with seal wear be studied carefully before a proper seal material can be selected. The paper presents the design and use of a rig to study the seal wear under approximate engine simulation conditions and describes the development and evaluation of a new seal material made as a result of the rig tests.