Spool Compressor Tip Seal Design Considerations and Testing

The simple analysis, design, construction and testing of the spool compressor’s tip seal is presented. Analysis yields key design considerations for seal geometry, preloading and pressure balance. Several seal designs are constructed and tested for leakage. Volumetric efficiency is calculated for three tip seal configurations and presented as a function of pressure ratio. It is determined that a two piece seal that expands axially results in less leakage. Further, it is determined that fluid pressure activation of the tip seal improves performance and eliminates the need for a highly loaded biasing spring. It is concluded that the tip seal performance is acceptable for a production compressor and can be constructed such that it would provide an acceptable service life