Wind loading on solar chimneys: from wind tunnel experiments to CFD simulation

摘要

The Solar Updraft Power Plant technology is a combined sun-wind energy solution for renewablernenergy harvesting. It is based on the natural updraft of warm air in a chimney and conversion into electric powerrnby wind turbines at the chimney foot. The tower structure is basically a circular cylinder, which may turn into arnhyperboloid at lower levels in order apply benefits of shape strengthening. The height of the tower is up to 1.5 kmrnand it is usually designed as a thin reinforced concrete shell. A preliminary investigation of the shell responsernunder an equivalent static wind load revealed the key role played by stiffening rings along the height. They allowrna better distribution of internal forces under wind loading, reducing risk of buckling and peaks of tension at thernwindward side. An extensive wind tunnel investigation has been recently performed atWiSt laboratory at Ruhr-rnUniversity Bochum (Germany) and at Criaciv laboratory at University of Florence (Italy). The tests highlightedrna new phenomenon regarding cross-wind loads, induced by a bi-stable and asymmetric flow distribution. Thisrnis created by compartments between stiffening rings along the tower.A further insight into the flow structures isrnachieved by CFD simulations. Results of both experimental and numerical studies are addressed in the paper.