Study of the Influence of Mass Flow Rate on the Thermal Efficiency of a Pressurized Air Volumetric Receptor

The pressurised air volumetric solar receiver, a component of a solar tower, is better suited for high-temperature operation than the surface solar receiver. To predict its behaviour, it is important to model the pressurised air volumetric solar receiver. Several parameters can influence the thermal performance of the volumetric receiver, including variations in the incident solar flux, the receiver's aperture area, and the mass flow rate. This study examines the influence of air mass flow rate on the thermal efficiency of the pressurised air volumetric receiver. The work defines the equations of the physical model and the principles of the numerical simulation. COMSOL Multiphysics 6.2 software was used to simulate performance. Increasing the incident solar flux improves the thermal performance of the receiver. However, increasing the mass flow rate regulates the receiver temperature. At low solar fluxes, the temperature difference ΔT is small, whereas at high solar fluxes, ΔT is significant, on the order of 200 K. Increasing the mass flow rate from 0.009 kg/s to 0.036 kg/s results in a change in the thermal efficiency of the volumetric receiver from 19% to 44%. The concentrated incident solar flux varies from 50 kW/m² to 175 kW/m².