Experimental Research of Supercritical Water Heat Transfer in Different Channels

The experimental research of supercritical water heat transfer has been performed on the supercritical water multipurpose test loop (SWAMUP) with tube, annular channel, and bundles. The normal heat transfer, heat transfer deterioration (HTD) and heat transfer enhancement were observed; and the heat transfer experimental data were obtained. The experimental results show that: the first kind of HTD caused by buoyancy effect only occurs with low mass flow velocity and high heat flux when the fluid temperature is below pseudo-critical point in all the tested channels and the second kind of HTD caused by acceleration effect always occurs when the fluid temperature reaches pseudo-critical point in tube and annular channel; the heat transfer enhancement occurs when the fluid temperature reaches pseudo-critical point with low mass flow velocity in tube; and the heat transfer enhancement in bundles is caused by the space grids. It is concluded that the heat transfer in bundles is better than in other tested channels.