Enhancing the Performance of a Laboratory-scale Solar Chimney by Geometric Modifications

High energy demand and severe environmental pollution due to extensive use of fossil fuels are among the most important issues that modern human has encountered recently. Renewable energies can mitigate the energy and pollution crisis to an extent. Solar energy is the most promising form of renewables for the countries with high levels of solar radiation. Among the solar energy technologies, solar chimney represents a simple and relatively low-cost concept of energy conversion. However, the major drawback of such a technology is its low performance and efficiency. A lot of geometric modifications have been made to the solar chimney systems. In this paper, the effect of radial guide vanes were tested on the overall performance of a laboratory-scale solar chimney. A solar simulator was developed for this study and the chimney was tested at three radial vane configurations: no-vane, 4-vane and 8-vane. The experimental data were utilized to find the suitable curve fitting models. After extracting the best fitted curves, they were used to calculate velocity and power in 3 different temperature difference levels for each vane configuration. The results of this study indicated that the 8-vane configuration had the highest effect on power and could averagely increase it by 75%.