Sensible Heating and Boiling Incipience in Free-Falling Dielectric Liquid Films
نویسندگان
چکیده
Controlling boiling incipience is of paramount importance for reliable operation of liquid-cooled microelectronic heat sources during power transients. This study focuses on heat transfer from a simulated multichip module to a falling film. Experiments have been performed to develop an understanding of the influence of surface tension and wetting characteristics on sensible heat transfer and boiling incipience in free-falling dielectric (FC-72) liquid films. The boiling results reveal that the vanishingly small contact angle of FC-72 precludes the application of correlations currently employed to predict incipience. Also, the temperature excursion commonly encountered upon boiling incipience in wetting fluids was nonexistent in all the experimental runs.
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Predicting the onset of nucleate boiling in wavy free-fabling turbulent liquid films
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REFERENCES 4. S. M. Yih and C. H. Chen, Heat transfer in the thermal entrance region of a turbulent falling liquid film underV. N. Murthy and P. K. Sarma, Heat transfer to nongoing heating or evaporation, Proc. 7th Int. Heat TransNewtonian laminar falling liquid films with smooth wave fir Conference, Munich, Vol. 3, pp. 125-130 (1982). free gas-liquid interface, Int. J. Multiphase Flow 4, 4135....
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