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ISSN Online: 2377-424X

ISBN CD: 1-56700-226-9

ISBN Online: 1-56700-225-0

International Heat Transfer Conference 13
August, 13-18, 2006, Sydney, Australia

DEVELOPED BOILING HEAT TRANSFER - FORTY YEARS OF THE MODEL OF "THE THEATRE OF DIRECTOR"

Get access (open in a dialog) DOI: 10.1615/IHTC13.p28.370
13 pages

Resumo

The paper traces rather specific background of development of de-facto major line of boiling heat transfer research putting in the forefront the role of momentum transport by evaporation in cooling mechanisms and boiling crisis and control of HTC by interphase thermodynamics on nucleation sites (the model of "the theatre of director" (MTD)). The paper also outlines main tasks of further research including the problem of multi-factoring of boiling heat transfer covering wide spectra of boiling processes. MTD (Shekriladze and Ratiani, 1966) is built upon so-called pumping effect of growing bubble (Shekriladze, 1966) representing the basic mechanism of boiling hydrodynamics and heat transfer. According MTD the "director" (superheating triggering bubble growth at nucleation site) controls integral cooling effect holding certain average superheating of boiling surface irrespective to intensities of separate cooling mechanisms. MTD presents exceptional line of analysis divergent to general approach of convective heat transfer theory always connecting HTC to intensity of certain cooling mechanisms. Following from MTD correlation (Shekriladze and Ratiani, 1966) describes HTC data during boiling of all classes of liquids including liquid metals surpassing in the context of universality classical turbulent pipe flow correlations. Rregardless of wide international publishing, MTD still is left aside of consideration. Investigation of the pumping effect is hampered by continuos misinterpretation and underinterpretation of important experimental results. All add up affects development of boiling heat transfer theory. Unfeasible attempts still last to establish developed boiling heat transfer law with the aid of so-called internal characteristics (densities of operating nucleation sites and bubble departure parameters). At the same time there are some R&D activities such as design of enhanced boiling surfaces, development of the theory of boiling crisis considering momentum transport by evaporation, application to boiling heat transfer of the theory of self-organized dissipative structures directly following from aforementioned major line of boiling heat transfer research. The paper presents just another attempt to call colleagues for wide fair discussion targeted at adequate evaluation of the state of art and outlining the most efficient ways of further research in the field of boiling heat transfer.