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The development of thermal regenerator theory from 1931 to the present

The representation of the resistance to heat-transfer in regenerators, due to the finite thermal conductivity and a significant thickness of the heat-storing packing, has been a continuing theoretical problem. The paper discusses the evolution of this theory from its early beginnings in the 1920s. In particular, the development of the pseudo-recuperator model in the first Melchett lecture by Kurt Rummel is discussed. The use of this early theory within modern modelling techniques for regenerators is outlined