Applicability of arrays of microjet heat transfer correlations to design compact heat exchangers
Abstract The article presents experimental studies on a compact heat exchanger with heat transfer intensification by means of impinging microjets. The pursuit to provide high performance of heat exchangers is a response to the demand both in economics and in the universal tendency to miniaturization of industrial equipment. This paper presents the design and tests of a prototype, microjet heat exchanger. The modular design of the heat exchanger allows to change its geometrical dimensions, as well as changing the heat exchange membrane material. The study of heat transfer in water water flow allows to determine the heat transfer efficiency, the characteristics of heat transfer, and the heat transfer coefficient values. Data were collected for the pressure drops in heat exchanger not exceeding 15 kPa, i.e. such as in conventional heat exchangers. Hydraulic characteristics of a model heat exchanger were obtained. Experimental values of heat transfer for jet impingement were calculated by means of Wilson's plot method. Obtained values of heat transfer coefficient were compared with literature correlations. Authors also proposed their own empirical correlation for jet impingement heat transfer coefficient.