Thermal analysis of a spiral solar receiver for a small central receiver system: an experimental and numerical investigation

An analytical model is shown in the present study to evaluate the outlet temperature of the spiral receiver for nine numbers of the mirrors. An external receiver was designed, manufactured and experimentally evaluated by the concentrated central receiver system in order to study the change of heat transfer characteristics of fluid and temperature within the receiver. Steady state numerical simulation was carried out by using ANSYS Fluent to determine the outlet temperature of water. CFD results were validated by using the experimental results. The temperature of the fluid was varied with the number of heliostats and the mass flow rate. A maximum temperature of 92.4˚ C was obtained for nine heliostats with a mass flow rate of 0.0016 Kg/sec at the solar noon and average temperature of 84.4°C for the whole day. The heat transfer coefficient and pressure drop obtained from the spiral coil tube were 1.44 and 1.97 times higher than those obtained from the straight tube, respectively.