Chapter 194 - Experimental investigation on pool boiling heat transfer of pure refrigerants and binary mixtures

Abstract

This chapter measures heat transfer coefficients in nucleate boiling on a smooth flat surface for pure fluids of R-134a, propane, isobutane, and their binary mixtures at different pressure from 0.1 to 0.6 MPa. Special emphasis is laid on the question, how the influence of the heat flux and pressure on the heat transfer coefficient is predicted at different saturation pressures. Several pool boiling heat transfer correlations for pure refrigerants are compared, and a new correlation is proposed based on the experimental data. A wide range of heat flux and mixture concentrations is covered in the experiment. The influences of pressure and heat flux on the heat transfer coefficient for different pure fluids are studied. Isobutane and propane are used to make up binary mixtures. Compared to the pure components, binary mixtures show lower heat transfer coefficients. This reduction is more pronounced as heat flux is increased. More binary mixtures and ternary mixtures are investigated and new heat transfer correlations are developed according to the experimental data in future.