An experimentally verified numerical model of finned heat pipes in crossflow

A numerical model is developed to predict heat rates associated with a heat pipe whose finned condenser section is subjected to external forced convection. Multiphase, conjugate heat transfer inside the heat pipe is predicted using a 2-dimensional model, while fluid flow and convection heat transfer within the fin array is described with a coupled 3-dimensional shear stress transport (SST) model. Predictions of local temperatures and overall heat rates are verified experimentally. The SST model is also validated with 3-dimensional direct simulations that show highly time-dependent, 3-dimensional phenomena in the fin array. A previously unreported phenomenon, localized depression of temperatures in the heat pipe wall, is presented and parametric simulations reveal the sensitivity of system performance to the number of fins and the air velocity in the fin array.