Abstract
Loop gravity-assisted heat pipe (LGHP) has the characteristics of
passive heat dissipation and wide application prospect. Different
working fluids lead to great differences in their working performance
(Critical heat flux (CHF)). Therefore, it is of great significance to
evaluate the performance of LGHP working fluid for its design. Based on
the basic theories of CHF and hydrodynamics, the pressure drop models of
laminar, smooth turbulence, and completely rough turbulence flows were
established, and an extensible two-phase composite property parameter
was obtained. Based on it, the physical property parameter of
transitional rough turbulent flow was also derived. Finally, experiments
were conducted and showed that there was almost a linear relationship
between CHFs and the derived physical parameter. Therefore, the physical
parameters derived in this paper can be used as good criteria for the
selection of LGHP working fluid.