Numerical Simulation on the Performance of a Combination of External and Cavity Absorber for Solar Power Plant

Optical and thermal simulation of a new up-down arranged dual-receiver for solar tower plant is presented in this paper. The top receiver is an external absorber type to serve as the boiling section, the bottom receiver is a cavity type to serve as the superheating section. The heliostat field is divided into two parts respectively for boiling and superheating section, it is quick and simple to control the heat flux distribution on both section. Then multi-aiming strategy is used for avoiding appearance of heat spot. For cavity receiver, a optimized layout for tubes is to increase convective heat transfer coefficient in the high heat flux religions. The concept of this new receiver is illustrated by a 10 MWe solar power plant that produces main steam at 513.5 °C and pressure of 10.12 MPa. Finally, this dual-receiver has a thermal efficiency of 91%.