Experimental investigation of pool boiling characteristics of surfactant solutions on bi-conductive surfaces

In this study, we conduct pool boiling experiments on pure copper and bi-conductive surfaces using sodium dodecyl sulfate as the surfactant and focus on the bubble behaviors and heat transfer performance of the solutions at the boiling crisis. In comparison with the deionized water, the surfactant solutions are found to effectively enhance the boiling heat transfer at low and medium heat flux. This could account for more active nucleation sites and less bubble coalescences, which can accelerate the formation and departure of bubbles. However, as mushroom bubbles are more easily formed in the surfactant solutions with the increase of the heat flux, the rewetting effect of the heater surface is inhibited, and the CHF is lower than that of the deionized water. For the bi-conductive surface, the CHF is found to be improved in the boiling of the surfactant solution compared with the smooth cooper surface, and the heat transfer deterioration are slowed down during the boiling crisis. Moreover, it is found that the low-thermal-conductivity material can hinder the lateral heat transfer, ensuring the generation of small bubbles and inhibiting the expansion of the dry-out area. (C) 2020 Elsevier Ltd. All rights reserved.