Heat Transfer in Circular Tubes with Supercritical Fluid Using the STAR – CCM + CFD Code.

Supercritical Cooled-Water Reactor (SCWR) which is planned to be deployed by 2030 derives its concept from Light Water Reactors Boiling Water Reactor (BWR), Pressurized Water Reactor (PWR) and Fossil Fired Coal Plant but with a simpler design. This research was undertaken in order to better understand the phenomena of heat transfer as applied to SCWR and also to test the applicability of Reynolds-Average Navier-Stokes (STAR-CCM+ CFD code). The experimental data [10] which employs supercritical CO2 as a simulant of water at 8 MPa was used to test the applicability. The computational simulation by STAR-CCM+ on the prediction of a 2-D axisymmetric heat transfer of carbon dioxide at supercritical pressure flowing upward through heated cross-section of a circular tube was performed with six (6) low-Reynolds number models; -epsilon AKN, EB, standard low-Re and V2F with two -ω turbulence models; SST and standard Wilcox treatment. The results obtained for heat fluxes of 20, 23, 30 and 40 kW/m2 and mass flux of 314 kg/m2s shows that Standard low-Reynolds turbulence models were seen to have better capabilities to predict the heat transfer behaviour of supercritical CO2 as observed in the experiment