A stud- on boiling heat transfer in thin liquid film. Part 1, in the case of pure water and aqueous solution of surface-active agents as working liquid.

This paper describes an experimental study to clarify the mechanism of boiling heat transfer when a heated surface is covered with a flowing liquid film maintained by a small circular jet of liquid impinging at the centre of heated surface. To evaluate the effects of surface tension on boiling heat transfer, pure water and aqueous solutions of surface-active agents are used as working liquids. The experimentally obtained heat transfer rates are classified into three different regions, and discussed quantitatively to obtain empirical expressions correlating heat transfer data in each region. Especially in the nucleate boiling region, it is found that a much higher nucleate boiling heat transfer can be sustained to a high heat flux region that usual pool boiling and the boiling heat transfer coefficient is proportional to the minus 0.4 powers of surface tension of liquid. (A)