The purpose of regenerative heat exchangers is to transfer the heat from one step or process of a cycle or system to an earlier step or process in the cycle or system such that the transferred heat is usefully absorbed rather than being discarded. The gas being heated is moved in a counter flow relative...http://www.google.ca/patents/US5533566?utm_source=gb-gplus-sharePatent US5533566 - Constant volume regenerative heat exchanger
