A new set of correlations for EHD enhanced condensation heat transfer of tubular systems

An improved set of correlations for evaluating the heat transfer coefficient of EHD assisted condensation heat transfer for tubular systems is presented in this paper. The correlations were developed by curve fitting a wide range of experimental data and then optimising the empirical constants so that the percentage deviation is less than +/-30%. The experimental data was classified in four categories: (I) condensation outside horizontal smooth tubes, (II) condensation inside horizontal smooth tubes, (III) condensation outside vertical tubes and (IV) condensation inside vertical tubes. The experimental data in each category included results obtained using various refrigerants and various electrode systems. The improved correlations were used to predict a total of 166 experimental data points. A comprehensive literature review of all available correlations for EHD assisted condensation heat transfer is also described in this paper. Two correlations that were identified to be simple were used to predict the above-mentioned data bank. These are the correlations of Choi and Reynolds and Didkovesky and Bologa. The Choi and Reynolds correlation was found to successfully predict heat transfer rates of condensation outside horizontal and vertical tubes and of condensation inside vertical tubes when high intensity electric field is applied. However, the Didkovesky and Bologa correlation was found to successfully predict only the results of condensation heat transfer outside vertical surfaces. (C) 2002 Elsevier Science Ltd. All rights reserved.