Marangoni effect on pool boiling heat transfer enhancement of self-rewetting fluid

Abstract

To clarify the Marangoni effect on nucleate pool boiling with different working fluids, a serial boiling experiments with the monocomponent fluid (water), the tradition binary fluid (5 wt% ethanol aqueous solution) and self-rewetting fluid (5 wt% butanol aqueous solution) have been comparatively carried out. During the pool boiling experiments, a boiling system using a horizontal heated wire was employed. The experimental results show that, due to Marangoni convection induced by the surface tension gradient, the critical heat flux (CHF) of the binary fluid (5 wt% ethanol aqueous solution) increased up to 1.52 times that of water, and the CHF of the self-rewetting fluid (5 wt% butanol aqueous solution) increased up to 1.91 times that of water. Utilizing dimensionless parameters with thermal Marangoni number (MaT) and solutal Marangoni number (MaS), the Marangoni effect have been quantitatively analyzed. It can be concluded that the Marangoni convection should be the key factors causing the pool boiling heat transfer enhancement.