Heat transfer performance of corrugated tube thermosyphons. 2nd report, Condenser performance.

Abstract

A two phase closed thermosyphon made of corrugated tube was developed to extend the application field of heat pipes. In the first paper, the thermal performance of the evaporator section was reported, including titled thermosyphons in addition to the vertical one. The present paper describes the thermal performance of the condenser section. The condensation heat transfer coefficient is proposed as a function of the modified Nusselt theory by three parameters : the Lockhart-Martinelli parameter to induce the effect of vapor flow on the condensing surface and two new parameters concerned with the effects of the inclination angle of the thermosyphon and the fill charge ratio of the working fluid. The former parameter has a linear relation with the condensation heat transfer coefficient and the latter two parameters have quadratic relations.