Cascaded SMA-Film Based Elastocaloric Cooling

This paper explores, develops and demonstrates a novel miniature cooling device using the combined elastocaloric effect of three cascaded Ti-Ni-Cu-Co films allowing to double the temperature span of a single film device being 7.6 K to 15 K. Ultra-low fatigue shape memory alloy (SMA) films are arranged in series to investigate in detail the effects of operation conditions and number of cascaded units on the cooling performance. By the new concept, the temperature span of the elastocaloric cooling device can overcome the adiabatic limit of the used elastocaloric material. The specific cooling power of a first-of-its kind demonstrator reaches 17 Wg
^-1
which is in line with performance predictions.