Experimental investigation on the R134-a spray cooling characteristics is presented in a closed loop system. A full-cone nozzle was applied to spray onto a heated circular copper plate. The characteristics of the R134-a spray cooling under a series of different volumetric flow rate were obtained. The results shown that volumetric flow rate improves the critical heat flux (CHF). And larger volumetric flow rate prevent the dry-out phenomenon under high heat flux. However, volumetric flow rate bring the adverse condition that reduces the system efficiency. The maximum CHF of 117.2 W cm−2 was achieved with 319 K target surface temperature at 0.356 L min−1. The results indicate that R134-a owns a great cooling characteristics in spray cooling system. Experimental Thermal and Fluid Science, 2014 Diagram of test system. Test system installation. Boiling curves of spray cooling at five flow rates. |