Heat Exchangers For Theramoacoustic refrigerators: Heat Transfer Measureemtns in Oscillatory Flow

摘要

During the pst fifteen years heat transfer in oscillatory flows has become the subject of increasing interest in the engineering community. Applications of oscillatory flows include, for example, the cooling of electronic equipment or alternative, environmentally safe refrigeration technologies, such as thermoacoustic refrigeration, pulse tubes or Stirling refrigerators. Important components of these refrigerators are their heat exchangers. In such devices the working fluid is subjected to oscillatory forcing which is a key part of the process, as opposed to situations where oscillations are generated with the aim to enhance heat transfer. Heat transfer in oscillatory, and often compressible, flows has not yet been completely understood, and the lack of design methodologies for heat excangers in such flows is one rason that efficiencies of these devices are limited. In this paper, convective heat transfer in steady flow is contrasted to measurements of heat transfer in oscillatory flow obtained by holographic interferometry in operating regimes characteristic of the heat exchangers. The results of the research are expected to lead to guidelines that will allow the design of heat exchangers with improved heat transfer performance.