Pool boiling enhanced heat transfer

The pool boiling heal transfer relations given above apply to smooth surfaces Helow we discuss some methods to enhance heat transfer in pool boiling. 

FIGURE 1L5 Pool boiling from smooth and structured surfaces on the same apparatus [40]. (a) sketch of cross sections of three enhanced heat transfer surfaces tested (b) boiling curves for three enhanced tubes and smooth tube. 

M. Fujii, E. Nishiyama, and G. Yamanaka, Nucleate Pool Boiling Heat Transfer from Micro-Porous Heating Surfaces, in Advances in Enhanced Heat Transfer, J. M. Chenoweth, J. Kaellis, J. W. Michel, and S. Shenkman eds., pp. 45-51, ASME, New York, 1979. 

Nucleate pool boiling has been very widely studied, and it would be impossible in the present context to give a detailed review of the vast amount of work done. Rather, some of the more salient points are addressed. The effect of various system parameters on pool boiling is first discussed, and then the mechanisms of nucleate pool boiling are reviewed with emphasis on recent findings. A number of the most widely used correlations for pool heat transfer are presented, and predictive models are discussed based on a more phenomenological approach. The effect of multicomponent mixtures on nucleate pool boiling and the various methods by which enhanced heat transfer can be obtained are also discussed. 

Furberg, R. and Pahn, B. (2007). A novel porous surface for enhancing heat transfer in pool and flow boiling. Proceedings of the Annex 33 Heat Pump Meeting, Stockholm. See www.compactheatpumps. oig. 

Wu WT, Yang YM (1992) Enhanced boiling heat transfer by surfactant additives. In Pool and External Flow Boiling. ASME, New York, pp 361-366... 

Launay S, Fedorov AG, Joshi Y, Cao A, Ajayan PM (2006) Hybrid micro-nano structured thermal interfaces for pool boiling heat transfer enhancement. Microelectronics Journal 37 1158-1164. 

Soiling Regimes and the Roiling Cunre 564 Heat Transfer Correlations in Pool Boiling 558 Enhancement cf Heat Transfer in Pool Boiling 572... 

The use of structured surfaces to enhance thin-film evaporation has also been considered recently. Here, in contrast to the flooded-pool experiments noted above, the liquid to be vaporized is sprayed or dripped onto heated horizontal tubes to form a thin film. If the available temperature difference is modest, structured surfaces can be used to promote boiling in the film, thus improving the overall heat transfer coefficient. Chyu et al. [43] found that sintered surfaces yielded nucleate boiling curves similar to those obtained in pool boiling. T-shaped fins did not exhibit low AT boiling however, a threefold convective enhancement was obtained as a result of the increased surface area. 

S. Yilmaz, J. J. Hwalck, and J. N. Westwater, Pool Boiling Heat Transfer Performance for Commercial Enhanced Tube Surfaces, ASME Paper 80-HT-41, ASME, New York, July 1980. 

Enhancement of Pool Nucleate Boiling Heat Transfer. Study of the enhancement of boiling heat transfer has been one of the fastest-growing areas of research in recent years. The annual publication rate in this area has grown to around 300 papers per year (Bergles [135]). 

V. K. Dhir, Pool Boiling Heat Transfer Recent Advances and Expectations for the Future, in Process, Enhanced and Multiphase Heat Transfer A Festschrift for A. E. Bergles, R. M. Manglik and A. D. Kraus eds., pp. 99-126, Begell House, New York, 1996. 

Kotaphakdee, P. and Williams, M.C. Enhancement of nucleate pool boiling with polymer additives. Int. J. Heat Mass Transfer 13 (1970) 835-848. 

The linkage between the enhancement of heat transfer at boiling of dilute polymer solutions and the elastic properties of the system is confirmed by the existence of the optimal concentration corresponding to (see Figure 7.2.14). Such peak performance at saturated pool boiling at atmospheric pressure of water solution of HEC QP-300 with molecular mass M 600 kg/mol was observed also elsewhere for instance, up to 45% increase in the boiling heat transfer coefficient, compared to that in pure water, was... 

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