Thermomechanical behavior of a plate ceramic solar receiver irradiated by concentrated sunlight

The thermomechanical behavior of a plate solar receiver with asymmetric heating is studied in this paper. The large-scale absorber/exchanger module is made of silicon carbide. It is irradiated by concentrated solar energy and heats pressurized air flowing inside textured channels up to high temperature. We look for the best compromise in terms of thermomechanical reliability, thermal efficiency and cutting conditions fulfillment of the exchanger. In particular, special attention has to be paid to its thermomechanical behavior in order to prevent the structure from being damaged. A parametric investigation (solar irradiance map, geometric characteristics: shell thickness, bridge between the textured and the smooth faces, number of channels) is carried out by 3D stationary thermal and thermomechanical simulations. The thermal gradient between the upper and the lower shells of the absorber is sufficiently reduced to guarantee the reliability of the structure. The numerical results show that the choice of the shape and levels of the solar irradiance map is crucial. The distribution of the most relevant incident solar flux and the geometry compromise are determined.