Mathematical modeling of sloped solar chimney power plants

Sloped solar chimney system is a solar chimney power plant with a sloped collector. Practically, the sloped collector can function as a chimney, then the chimney height can be reduced and the construction cost would be reduced also. A mathematical model based on the continuity, momentum, energy, and state equations is developed for the sloped solar chimney system in this study. The flow details inside a collector are included in the model. The mathematical model was solved numerically using an iterative technique. Then, the numerical simulation was performed using the commercial CFD package. The consistency of the predictions of the mathematical model and that of the CFD package justifies the validity of the proposed mathematical model. A detailed study of the plant characteristics is done. Results show that using a near-unity ratio of the collector inlet flow area and the collector exit flow area might cause some problems. In addition, the assumption that the density differences in the collector and that in the chimney are approximately equal is investigated. The study shows that this assumption provides a large overprediction of the results. The effects of the chimney height and the collector area on the plant performance are also illustrated. (C) 2012 Elsevier Ltd. All rights reserved.