CFD Analysis of Hybrid Solar Chimney Power Plant

Abstract

In this study, a novel approach has been proposed as a solar chimney integrated with an external heat source to extend the system operation during the absence of solar energy. Flue gas channels have been utilized to exchange heat with the air inside the collector of the solar chimney. The hybrid solar chimney has been investigated numerically by ANSYS-Fluent software, using discrete ordinates radiation model. The hybrid system was simulated in 3D, steady-state by solving Navier-Stokes and energy equations. The numerical results have been validated using experimental measurements of a conventional solar chimney. The influence of flue channels on the system performance was predicted and analyzed in hybrid mode. With 0.002 kg/s of flue gas at 100°C injected in flue channels during the daytime; hybrid mode results demonstrated enhancement of 24% and 9 % for velocity and temperature, respectively. The power generation was enhanced by 56%. It has been proved that the proposed technique is able to resolve the set back of night operation problem of the solar chimney plants.

Daily dynamic performance of a solar chimney power plant integrated by waste heat recovery

“…Waste heat source(s) were proposed to be incorporated into the plant for waste heat recovery and power generation [12][13][14][15][16][17]. For example, Ghorbani et al proposed a hybrid SCPP for waste heat recovery and power generation, where the waste heat from hot flue gas in a 250 MW steam power plant was injected above the turbine at the chimney base and the waste heat from hot water was injected through the heat exchanger installed at the collector periphery.…”

“…Aurybi et al performed steady‐state CFD simulations of a hybrid SCPP with flue gas waste heat directed to flow through four channels underneath the collector cover towards the chimney base. In the hybrid SCPP both the velocity and the temperature of the air inside the plant were enhanced [14]. Habibollahzade et al proposed a hybrid SCPP, where the waste heat from the municipal solid waste gasification–combustion facility was injected into the chimney just below the turbine and over the collector exit.…”