Thermal-hydraulic-structural analysis and optimization of supercritical CO2 solar tower receiver

Abstract

The supercritical CO2 receiver in solar tower power plants withstands high temperature and large thermal stress caused by highly non-uniform solar radiation. The application of eccentric tube in solar power tower plants was innovatively proposed to solve this problem. A three-dimensional thermal-fluid-mechanical coupling model of complex eccentric tube structure with high non-uniform heat (NUH) flux was constructed. The results showed that the eccentric receiver was appropriate for non-uniform and half-perimeter uniform heat fluxes. The eccentric tube exhibited a considerable improvement in tube-wall refrigeration, reflected in the maximum temperature and stresses. The highly NUH flux distribution in the receiver proved to be the main factor causing plastic deformation. Moreover, the distribution of the temperature, stress, and generalized thermal deviation factor (GTDF) with eccentric distance were also determined—they all decreased with an increase in the eccentric distance. Consequently, the key operating parameters for the eccentric receiver performance were investigated. The maximum temperature of the eccentric receiver was greatly reduced by 46.6–109.1 K and the GTDF was effectively reduced by approximately 13.9–51.4% under all the simulated working conditions—indicating the eccentric receiver to be a superior candidate to the current cavity tubular receiver of solar power tower plants.