On the criteria of nucleate pool boiling enhancement by surfactant addition to water

By testing against collected data from twelve surfactant additives, criteri a for a given surfactant as a competent additive in enhancing nucleate boil ing heat transfer of water is proposed in this work. As a result of the cri teria, high solubility, high equilibrium surface tension depression, and lo w equilibrium contact angle depression are required. A surfactant is incapa ble of enhancing boiling of water, in which it dissolves sparsely. For a hi ghly soluble surfactant, boiling heat transfer enhancement by its addition is enhanced by the depression of equilibrium surface tension but suppressed by the depression of equilibrium contact angle. These two effects counterb alance each other and result in different degrees of boiling enhancement. S urfactant additives can be categorized accordingly.