Flow boiling heat transfer and pressure drop of water in a plate heat exchanger with corrugated channels at low mass flux conditions

Abstract

The plate heat exchanger (PHX) has been widely used as a heat exchanger in fresh water generators (FWGs) at low mass flux conditions. In this study, the flow boiling heat transfer and pressure drop characteristics of water in a PHX for the FWG were measured by varying mass flux from 14.5 to 33.6 kg m(-2) s(-1), heat flux from 15.0 to 30.0 kW m(-2), and mean vapor quality from 0.09 to 0.6 in the pressure range of 112-121 kPa. The flow boiling heat transfer of water in the PHX was in the convective boiling region. The flow boiling heat transfer coefficient decreased with increasing mean vapor quality and decreasing mass flux. However, the effect of the heat flux on the flow boiling heat transfer coefficient was almost negligible. In addition, the two-phase frictional pressure drop increased with increasing mean vapor quality and mass flux, but it remained nearly constant according to the heat flux. Two-phase heat transfer and pressure drop correlations for water in PHXs were developed based on the measured data. The proposed heat transfer and pressure drop correlations showed mean absolute deviations of 4.4% and 10.4%, respectively, compared with the measured data. (C) 2014 Elsevier Ltd. All rights reserved.