20.500.12556/RUL-125551 Thermo-hydraulic evaluation of oscillating-flow shell-and-tube-like regenerators for (elasto)caloric cooling The development of novel regenerators for caloric cooling applications requires a detailed evaluation of their thermo-hydraulic properties. Structures similar to shell-and-tube heat exchangers are one of the most promising geometries for elastocaloric technology since they exhibit high thermal performance and can be applied under compressive loading to overcome the limited fatigue life of elastocaloric materials normally experienced in tension. However, thermo-hydraulic properties of shell-and-tube-like structures at the conditions relevant for caloric cooling applications (oscillating counter-flow regime at low Reynolds numbers (<2000) and water as a heat transfer fluid) have not yet been characterized. In this paper, comprehensive oscillating-flow passive experimental characterization and numerical modeling were used to determine their thermo-hydraulic performance. By varying the tube wall thickness, the tube/rod diameter, the spacing between the tubes/rods, and the channel height (baffle distance), nine different regenerators were assembled and analyzed for their thermal effectiveness, convective heat transfer and friction losses. New Nusselt number and friction factor empirical correlations were developed and compared with packed beds and parallel plate regenerators (as two most widely applied regenerator geometries in caloric cooling). We show that shell-and-tube(rod)-like regenerators can reach relatively high effectiveness (up to 0.92) and can present an excellent compromise between heat transfer and pressure drop properties. The shell-and-tube-like geometry can serve as a highly efficient (elasto)caloric regenerator, but dense packing with a small(er) hydraulic diameter is required to further increase the convective heat transfer coefficients and the NTU values. The obtained results should serve as guidelines for overall optimization of compression-loaded shell-and-tube-like elastocaloric regenerator. heat regenerator shell-and-tube heat exchanger elastocaloric cooling thermal effectiveness Nusselt number friction factor regenerator toplote kotelni prenosnik toplote elastokalorično hlajenje učinkovitost Nusseltovo število faktor trenja true false true Angleški jezik Slovenski jezik Članek v reviji 2021-03-24 12:23:20 2021-03-24 12:23:26 2022-09-05 03:51:19 0000-00-00 00:00:00 2021 0 0 15 str. Vol. 190, art. 116842 May 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 519.876.5:621.57(045) 1359-4311 10.1016/j.applthermaleng.2021.116842 57027843 1861910 RAZ_Ahcin_Ziga_2021.pdf RAZ_Ahcin_Ziga_2021.pdf 1 B9EB4035B9F74A35B60BEDE35DB5C3F3 638140d0ef02007336f32acbe8faf11df97b3c92e12f89a9777f63d4e3e900ff bb76c005-a1bb-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=141309 https://www.sciencedirect.com/science/article/pii/S135943112100291X 1 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=141308 Fakulteta za strojništvo 0 0 0