Effect of operation parameters on the thermal performance of a solar parabolic dish with cylindrical cavity receiver to generate superheated steam

A numerical model is developed to simulate and study the effect of altering the operation parameters on the thermal performance of a solar parabolic dish with a cylindrical cavity receiver to generate superheated steam. It was assumed that a steady-state, incompressible flow at the inlet section of the receiver is dry saturated steam, assuming the k-ω turbulent model. In addition, the cavity receiver is subjected to a uniform heat flux at its internal surface area and is perfectly insulated at its outer surface area. Each inlet steam temperature value (105, 106, and 112 ℃) is simulated with each mass flow rate value (0.011, 0.015, and 0.18 kg/s) at the receiver inlet section. A test rig was made. It consisted of a (2m) diameter parabolic dish, with a cylindrical cavity receiver of (17 cm) inlet diameter and (25 cm) length. A helical copper coil of (10 mm) inlet diameter and (6 m) length is fixed on the inner surface of the cylindrical cavity receiver made of stainless steel. The predicted numerical results were confirmed when validated with the experimental measurements taken during the experimental tests. It was found that the maximum thermal efficiency of (63.3 %), the maximum value of the receiver useful heat of (1592.4 W), and the maximum value of the degree of superheat of (81.38 °C) were achieved when operating at (0.011 kg/s) of steam mass flow rate at (112 ℃) of saturated temperature at the inlet section of the receiver.