Heat Transfer in Liquid Piston Isothermal Air Compressor/Expander

Abstract

An "open accumulator" high pressure compressed air approach has been proposed for storing excess wind energy locally. This approach does not require special geological sites or additional fossil fuel as in conventional compressed air storage (CAES) approach. It relies on a combined hydraulics and pneumatic approach to attain both high energy density and power density. A critical element in the approach is an isothermal high pressure air compressor/expander. In this regard, research is underway to develop a liquid piston based compressor/expander with improved heat transfer and sealing properties.