Convective Heat Transfer of Binary Mixtures under Flow Boiling Conditions

The present study represents part of an effort in considering the replacement of ethylene-glycol/water mixtures with propyleneglycol/water mixtures for engine cooling in automotive application. Experimental results are presented for the heat transfer coeffic ient under flow boiling conditions for water and mixtures of water with ethylene-glycol and propylene-glycol. The range covered includes the single-phase non-boiling region through the fully developed subcooled flow boiling region to saturated boiling. Since there are no predictive methods available in literature for subcooled flow boiling of binary mixtures, a preliminary comparison with pure component correlations is presented in the fully developed boiling region. Further work is being undertaken to extend the methodology to the partial boiling region and the significant void region.