Numerical analysis of wind supercharging solar chimney power plant combined with seawater desalination and gas waste heat

Abstract

Performance investigation of the wind supercharging solar chimney power plant combined with seawater desalination and gas waste heat (WSCPPDW) was conducted in this study. The objective of this paper is to investigate the influence of operational and structural parameters on the WSCPPDW performance and to analyze the flow field characteristics in the WSCPPDW. The mathematical model of WSCPPDW, proposed before, could hardly reflect the effect of structural parameters and flue gas jet. Hence, 3D numerical simulation of WSCPPDW was carried out, using CFD ANSYS Fluent. To explore the optimum operational and structural parameters of WSCPPDW, simulations with different turbine rotational speed, nozzle length, chimney outlet radius and chimney mixing section length were conducted. The results show that the flue gas jet could form a high-temperature and high-speed jet area in the chimney, having entrainment effect on the surrounding airflow. Besides, as the turbine rotational speed increases, the freshwater yield decreases and the turbine shaft power increases first and then decreases, getting peak at 200 rpm. With the increase of nozzle length, the freshwater yield and turbine shaft power first increases and then decreases; With the increase of the chimney outlet radius, the freshwater yield and turbine shaft power first increases and then decreases; As the chimney mixing section length increases, the freshwater yield and turbine shaft power increases significantly at first and then decreases slightly. From the parametric study, it is concluded that for the turbine rotational speed, the nozzle length, the chimney outlet radius and the chimney mixing section length of 200 rpm, 6 m, 9 m and 60 m, respectively, better performance could be achieved. Concretely, the power generation and hourly freshwater yield of WSCPPDW reached 377.9 kW and 20.3 ton/h, respectively.