A numerical prediction on heat transfer characteristics from a circular tube in supercritical fluid crossflow

Studies on fluids at supercritical pressure have been developed in a rapid-growth manner so that geometries are not restricted to circular tube. This paper is devoted to conduct a brief review of the recent main experiments on supercritical fluids such as CO₂, water, R134a and n-decane, and to comment the findings. In addition, this paper discusses the probability of supercritical fluids flowing across tube bundles for the frequent use in shell-and-tube heat exchangers in supercritical power cycle systems. A numerical prediction of flow patterns and heat transfer characteristics of a circular tube in supercritical water crossflow is carried out to make a fundamental investigation of the application of supercritical fluids on external flows. Results indicate that the influence of heat flux on heat transfer in crossflow is similar with that for in-tube flows. The thermal physical properties significantly affect the heat transfer and the flow patterns also show unique characteristics with the change of boundary conditions.