Renewable Energy Production by Solar Chimney: The Influence of Curved Guide Vanes on the Performance of a Solar Chimney Using CFD Simulation

The aim of this study is to investigate the effect of the guide vanes on the efficiency of the turbine of solar chimney power plant using Computational Fluid Dynamics (CFD). In this study, a 3-Dimentional CFD simulation of solar chimney power plant based on the Manzanares prototype is performed. The CFD simulation is validated by comparing the experimental data from the Manzanares prototype and simulation data with both 2D and 3D cases. To capture turbulent flow inside the chimney, the SST − turbulence model is used. The first object is to investigate the flow performance under the influence of the guide vanes while there is no turbine. Five cases of solar chimney with different guide vanes designs, which are labeled with the angle at the end of the vanes, are examined. The five angles studied in this work are 30° , 45° , 60° , 75° , and 90° guide vane. The flow angle at the vanes’ exit and the temperature difference are calculated and analyzed. The swirling flow is also visualized with flow streamline. The design of the guide vanes is proved to directly affect the flow direction and the heat stored inside the blade chamber is negatively related to the blade angle. The second object is to study the change in power under different turbine rotational velocity and different guide vanes. In this part, a twelve-blade real turbine is included and installed right above the exit of the guide vanes at the start of chimney. Various cases are run for three angles, 30°, 60°, and 90° guide vane, and six rotational velocities, from 20 rpm to 120 rpm. The multiple reference frame (MRF) method is used in this part of the study to save computational resource. Thrust force, torque and power are extracted and analyzed. It is found that the maximum power of 82.2 kW is reached by the case of 30° guide vane at 80 rpm. Comparing to the power of the 90° guide vane at the same rotational velocity, which is 66.3 kW, the increase is about 23.9%. Finally, the deformation of the turbine of the cases run in the second part is examined using Finite Difference Method (FEM). One way fluid structure interaction (FSI) method is used in this section. The deformation and von Mises stress of the turbine are calculated from the imported pressure. The maximum von Mises stress appears at the joint between the blade and the central rotor is obtained for 20 rpm and angle of 90° guide vane