Diagnostics of coolers with oscillating fluid motion: Part II. Entropy generation Original Research Article

Instruments dedicated to entropy generation (Sgen) measurements are not readily available. In order to determine Sgen we distinguish two types of transport rate diagnostics: one special low temperature opportunity is the rate measurements in superfluid liquid helium; another type is the measurement of entropy generation in cryocooler components (e.g. contact domain resistance) and in the entire cooler. We focus on the coolerʹs total entropy generation rate with access via power input. Two categories of stage arrangements of a two-stage cooler result in different optimum stage parameters.