Model of heat transfer in the stagnation point of rapidly evaporating microjet
The paper presents investigation into the single water microjet surface cooling producing evaporating film. Reported tests were conducted under steady state conditions. Experiments were conducted using the nozzle size of 70 and 100 μm respectively. In the course of investigations obtained were experimental relations between heat flux and wall superheating. It was proved that the phenomenon is similar to that of pool boiling but the boiling curves are showing a smaller value of critical heat flux (CHF) that the stagnant pool boiling. Values of CHF are also reduced with decreasing liquid subcooling. Theoretical model of surface cooling by evaporating microjet impingement in the stagnation point was described theoreticaly. Results of experiments were compared with predictions by the model showing a good consistency.
Garimella S. V., Rice R. A.: Confined and submerged liquid jet impingement heat-transfer. JHT 117(1995), 871-877.
Mikielewicz D., Muszynski T.: Experimental study of heat transfer intensification using microjets. In: Proc. Int. Symp. on Convective Heat and Mass Transfer in Sustainable Energy, Hammamet 2009, Tunisia.
Goldstein R. J., Timmers J. F.: Visualisation of heat transfer from arrays of impinging jets. Int. J. Heat Mass Transfer 25(????) 1857-1868.
Meyer M. T., Mudawar I.: Single-phase and two-phase cooling with an array of rectangular jets. Int. J. Heat Mass Transfer 49(2006), 17-29.
Sung M. K., Mudawar I.: Single-phase and two-phase heat transfer characteristics of low temperature hybrid micro-channel/micro-jet impingement cooling module, Int. J. Heat Mass Transfer 51(2008), 3882-3895.
San J., Lai M.: Optimum jet-to-jet spacing of heat transfer for staggered arrays of impinging air jets. Int. J. Heat Mass Transfer 44(2001), 3997-4007.
Liu Z.-H., Zhu Q.-Z.: Prediction of critical heat flux for convective boiling of saturated water jet impinging on the stagnation zone. J. Heat Transfer 124(2002), 1125-1130.
Omar A. M. T., Hamed M. S., Shoukri M.: Modeling of nucleate boiling heat transfer under an impinging free jet. Int. J. Heat Mass Transfer 52(2009), 5557-5566.