Abstract    In this paper the steady state performance of a variable conductance heat pipe, which its working fluid consists of two components (R11+ R113) is modeled. The role of the liquid film momentum and axial normal stresses are considered by use of the mean property of mixture and the governing equations are solved by conventional numerical methods. The results of the present model have been compared with other numerical models and experimental works done by other investigators. The model presented could be used for optimization studies and design of variable conductance thermosyphons.

Keywords    Thermosyphon, Variable Conductance, Binary Mixture

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