SPECIFICS OF THE FLOW OF SUPERCRITICAL WATER UNDER CONDITIONS OF MIXED CONVECTION

A study of the specifics of supercritical water flow under conditions of mixed convection was made on the basis of CFD modeling. The results of comparison of the numerical solutions obtained in the presence and absence of the buoyancy forces are given. It is shown that the influence of Archimedean forces on the flow structure is localized in the central region of tube length. The data of computer modeling of supercritical water flow pattern with the variation of heat flux q on the tube wall are obtained. The dependence of the localization of mixed convection zone from the value of q is established. The change of the local Richardson number in the context of the effect of the localization of buoyancy forces action is analyzed. For the conditions under consideration, the dependence of turbulent transfer intensity on the effect of Archimedean forces is investigated. It is shown that this action causes oppression of turbulent transport, which is most significantly manifested near the wall of the tube.