PROMISING TRENDS IN DESIGNING EFFECTIVE HEAT TRANSFER SURFACES

Analysis is made of the modern trends in heat transfer enhancement in channels with reference to different-purpose compact heat exchange apparatuses. Requirements are formulated for high-effective heating surfaces and, bearing this in mind, different methods of heat transfer enhancement are analyzed. It is show that the methods of artificial flow turbulization which are based on a detailed analysis of the flow structure can give the most advantageous results.
Consideration is made of the specific features of the method of heat transfer enhancement which has been developed at the Moscow Aviation Institute. The results of several year's investigations are presented on heat transfer enhancement in gas and liquid channel flow, at film and surface boiling, at film, drop and film-drop condensation, at vapour condensation of vapour-gas mixtures, as well as under fouling conditions. Introduction of the developed heat transfer enhancement method allowed both a 1.5 ÷ 2.5 - fold reduction of a heating surface at prescribed heat power and pumping power of heat carrier and improvement of the performance parameters of heat exchangers due to reducing scaling and contamination in them.