Advanced Regenerators for Cryocoolers Operating at 10-100 Kelvin

The performance of high speed cryocoolers is highly dependent on an effective regenerator which has high heat capacity, large surface area, and low pressure drop. These factors can increase refrigeration capacity, lower operating temperatures and improveefficency. Parallel plate regenerators have been shown to be the most effective geometry possessing most of these characteristics. However, implementing a parallel plate configuration in a compact cryocooler is difficult. The proposed work makes use of anembossed metal ribbon which produces a controlled gap between layers when spirally wound and stacked in a cylinder to form the regenerator which approximates the parallel plate geometry. Such an arrangement allows complete control over the ribbon material,the gap width, and the ribbon or plate thickness. These characteristics can be optimized for any temperature, cycle speed, or refrigeration capacity. a regenerator design and model will be developed for a class of cryocoolers and an embossed ribbon willbe produced based on this work.The proposed regenerator configuration is applicable to all commerically available cryocoolers using regenerative type heat exchangers. In a retrofit or new product, the efficiency would improve by up to 50% allowing for anequal reduction in input power. The cost of these regenerators is expected to be comparable with presently available regenerators in their respective temperature ranges.