The heat transfer of saturated nucleate pool boiling in aqueous solutions of Triton SP-190 and SP-175 on a horizontal tubular heater was experimentally investigated. Equilibrium and dynamic surface tensions and equilibrium contact angles were also measured for the surfactant solutions. Experimental results show that while the equilibrium surface tension and contact angle were both depressed considerably, the addition of Triton SP surfactants to water hardly made any difference to the value of nucleate boiling heat transfer coefficient; however, boiling incipience excursion was found for more concentrated solutions. For the boiling heat transfer results to be correlated with interfacial properties of surfactant solutions, two postulates are required first. As a consequence of the postulates, nucleate boiling heat transfer in Triton SP surfactant solutions is enhanced due to a reduction in equilibrium surface tension and decreased due to a reduction in contact angle; however, these opposing effects, may offset each other by coincidence and result in a lower limit of the possible nucleate boiling enhancement by surfactant additives. A fitted correlation was satisfactorily proposed.
Enhanced Heat Transfer
Volume 9, 2002 - Issue 3-4