Effect of guide wall on the potential of a solar chimney power plant. (October 2016)

• Record Type: Journal Article
• Authors: Hu, Siyang; Leung, Dennis Y.C.; Chen, Michael Z.Q.; Chan, John C.Y.
• Is Part Of: Renewable energy. Volume 96:Part A(2016)
• Page Start: 209
• Page End: 219
• Publication Date: 2016-10
• Subjects: Solar chimney power plant -- Guide wall -- Power output -- CFD -- Small-scale prototype; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2016.04.040
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: A solar chimney power plant (SCPP) converts solar thermal energy into electricity by generating a buoyant flow in a chimney. To assist the air flow in shifting its direction from horizontal to vertical, a guide wall (GW) is usually set in the collector-to-chimney transition region. The primary objective of this study is to examine the impact of the GW geometry on the power output of a SCPP. A reduction in mass flow rate after adding a GW in the system was observed in a small-scale experimental prototype. Numerical simulations on a large-scale SCPP further found that the mass flow rate was linearly and inversely proportional to the increase of GW height. The driving force, however, nonlinearly increased with increasing the GW height. Subsequently, the potential maximum power output, which was mainly governed by the driving force, increased with increasing the GW height. Furthermore, a divergent-chimney system which can improve the performance of SCPPs had different reactions with the geometry of GWs compared with a cylindrical-chimney system. Under the optimal GW configuration, the power output of the SCPP increased by ∼40% in a cylindrical-chimney system and by ∼9.0% in a divergent-chimney system with respect to the system without a guide wall. Highlights: Geometric effect of guide wall on SCPP performance is examined numerically and experimentally. System potential is mainly affected by the guide wall height. Mass flow rate in system linearly reduces with increasing the guide wall altitude. Driving force and potential power output improved by heightening guide walls. Improvement in a divergent-chimney system is smaller than a cylindrical one.