Optimization of embedded inclined open-ended channel in natural convection used as heat drain

Abstract

The heat transfer and self-driven fluid flow within an inclined open-ended channel is presented. The channel is assumed thin and is embedded into a solid. The application that we consider is for the cooling of permafrost on which an infrastructure such as a road is built. A CFD model and a scale analysis are developed. Optimization of the channel is performed by varying its thickness, inclination angle, and entrance length. The overall thermal conductance between air and ground is provided. Based on an equivalent thermal circuit of the inclined channel, transient simulations of the ground are performed in order to verify whether the heat drain helps to elevate the maximal thawing interface during the year. For the case considered, the front moved upwards by more than 30 cm with the heat drain. The model and results could be applied to several other types of embedded open-ended inclined channels.