Simple theory of a Malone engine

Practical liquid engines called Malone engines use a regenerative or recuperative cycle, like the Stirling cycle. A theoretical model of the Malone engine that is realistic enough for comparison to experiment, yet still simple enough for intuitive grasp of the engine´s features, is presented. The principal results obtained with the model are the time-averaged heat and work resulting from each of the most important effects taking place in the engine. It is shown that Rankine heat pumps and Malone heat pumps with equal heat-pumping capabilities require compressors of comparable volumetric flow rates and hence of comparable complexity and size, but the heat exchangers for the Malone heat pump are expected to be orders of magnitude smaller than those for the Rankine-cycle heat pump