ANALYSIS OF EVAPORATION OF NONAZEOTROPIC REFRIGERANTS IN A HORIZONTALTUBE

Based on the two-phase separated model, a detailed one-dimensional mod el for binary mixtures had been proposed to study the in-tube evaporat ion in a horizontal tube. The present model can predict the detailed v ariation of the composition, temperature, heat transfer rate and press ure drop of various binary mixtures under constant heat flux, counter- flow, or parallel-flow conditions. The predicted results agree favorab ly with the Takamatsu et al. [Int. J. Neat Mass Transfer 36, 3555-3563 (1993)] and Jung et al. [Exp. Heat Transfer 2, 237-255 (1989)] experi mental data. Also, it is found that the full evaporation of the non-az eotropic refrigerants may require a corresponding temperature higher t han the saturation temperature of the less volatile component. The non -linear variation of the property plays an important role in the heat transfer and pressure drop characteristics of the refrigerant mixtures . Copyright (C) 1996 Elsevier Science Ltd.