Development and comparison of design concepts for elastocaloric cooling and heating devices

In the past years elastocaloric cooling gained considerable interest as an eco-friendly and more efficient alternative to the prevalent vapor compression-based cooling processes. Numerous international research projects have addressed material optimization, extensive process investigation as well as the development of first elastocaloric cooling devices. As the worldwide first continuously operating cooling demonstrator based on SMA wire bundles with air as heat transferring medium, the device developed by Kirsch et. al. from Saarland University deserves special mention.

To ensure successful introduction of the technology, the development of future elastocaloric cooling and heating devices needs to address varying industrial requirements and application-oriented design. Research topics include the optimization of installation space as well as adaptable thermal power and special demanded heat transferring media. Therefore, a new systematic approach to develop and design elastocaloric cooling and heating devices is presented in this contribution.

The presented approach includes a morphological box, which identifies basic characteristics for the description of most conceivable devices. The morphology allows the creation of completely new device concepts or vary and adapt special requirements on existing configurations. In addition to this, four fundamental criteria were defined to categorize different types of device concepts, which are movement of SMA material (rotatory, translatory), direct or indirect heat exchange, transfer medium (fluid, gas) and medium flow direction in relation to the SMA elements. Based on the first demonstrator, the elaboration of three new device concepts will be presented by using the systematic approach. Furthermore, the concepts will be compared according to objective criteria.