A new Wankel-type Compressor and Vacuum Pump

Abstract of a Paper presented in London on 13 Sept 2017

When the Wankel principles were first published in the early 1950s most of the initial work was aimed at developing a compressor . At that time many of the characteristics appeared to promise a superior machine than hitherto known. However, all the early designs resulted in a high value for the minimum clearance volume (CV) and this problem was never overcome.

Knowledge now gained from the development and manufacture of the Wankel engine has enabled the evolution of a new compressor concept where the rotor flank, radially very close-fitting over its central area, provides gas sealing with the housing bore. The rotor has an increased radial clearance towards the apices which makes the machine practical to manufacture. The ‘nesting’ of the rotor flank with the housing bore at the end of the exhaust stroke results in an extremely small CV.

This machine promises to possess an exceptional combination of all the attributes which are important in achieving high energy efficiency in positive-displacement compressors and vacuum pumps:

– near-zero CV

– low mechanical friction losses

– low internal gas leakage (assisted via oil flooding)

– high volumetric efficiency.

In addition it is compact, lightweight, vibration-free, consists of few components, and can be built in any chamber size.

The Paper discusses the features and characteristics of the design.