Experimental investigation to the heat transfer characteristics of water in vertical pipes under supercritical pressure

Heat transfer characteristics of supercritical water in a vertical upflow tube with full-circumferential heating are investigated experimentally. The effects of mass flow, heat flux, and pressure on the heat transfer are analyzed via the experimental data in detail. Because of the abrupt variation of the thermophysical properties under supercritical pressure, heat transfer enhancement phenomenon is observed when the fluid bulk temperature approaches the pseudo-critical temperature. With increasing of mass flow and pressure, and with decreasing of heat flux, heat transfer is enhanced obviously. By curve-fitting of the experimental data, an empirical correlation for forced convection heat transfer of supercritical water is obtained with average relative error of 11.8%.