Computational Assessment of Double-Inlet Collector in Solar Chimney Power Plant Systems

Abstract

Solar chimney power plant systems (SCPPS) offer a simple and reliable way to generate electricity using solar radiation to drive a flow of buoyant air. A typical SCPP setup includes a collector, a tower, and a turbine or several turbines. Current SCPP designs have low thermal efficiency: only between 0.5% and 5% of the incident solar energy is converted into electricity. Inefficiencies result partially from limited mass flow rates through the tower. It is therefore desirable to provide a new design for the collector to increase the inlet air mass flow rate. In this paper, we present a double-inlet collector concept and results of numerical analysis to evaluate this design in terms of flow rate improvement. Computational fluid dynamics (CFD) was utilized to perform the numerical modeling and simulation (M&S) by using a finite volume method package. The Manzanares prototype (the only operational solar tower power plant with available published reports) is selected to implement the double-inlet collector design and study its effect on the power plant. Beside this case, we fabricated a 1/1000 scale model of the Manzanares prototype which enables us to measure the filed variables experimentally. Validation analysis was performed to quantify the reliability of our numerical model with respect to the available experimental data. We obtained a significant increase (14%) in the available output power by using the double-inlet collector.