EXPERIMENTAL STUDY OF EXIT VELOCITY EFFECT O N HEAT TRANSFER WITH IMPINGING SUBMERGED CIRCULAR JETS AT STAGNATIO N POINT
Experimental study was performed systematically to investigate heat transfer characteristics at the stagnation point from a simulated microelectronic chip of 5?mm×5?mm with impinging submerged circular jet, using R113 as the working fluid.Included are single-phase convective heat transfer,incipient boiling superheating, nucleate boiling heat transfer and burnout.The results showed that exit velocity had no influence on incipient boiling point and fully-developed nucleate boiling heat transfer curves, and that single-phase convective heat transfer coefficient and critical heat flux increased with enhanced jet exit velocity,while temperature overshoot decreased.While exit velocity was beyond 10?m·s -1 ,the high heat flux portions of impingement boiling curves needed to be corrected in order to align with pool boiling curves at the same fluid subcooling.