Analysis of wind loads-induced effects on heliostat in a solar power tower plant

Abstract

In the present work, the deterioration of the reflected beam quality due to gravity loads, static wind loads and temperature effect will be the subject of this study by the determination of the mathematical model deformation of the 105 m2 heliostat reflecting surface using MATLAB code COMSOL CFD code was used to simulate the effect of wind barrier on the reduction of wind velocity and wind turbulent kinetic energy. Finally, Sandia-92 analytical method was used for the calculation of wind loads forces and moments for an isolated and in-field heliostats using Excel code. The main results for this study are: The heliostat reflective surface deformation is in maximum when the elevation angle is near zero. Temperature difference has no effects on heliostat reflective surface deformation. The components of the heliostat which accentuate the change in shape of the reflecting surface of the heliostat are the support tube and trusses. It is therefore necessary to change the shapes of these two components without increasing weight or reduce their weight using composite materials. The recirculation regions in heliostats field affects their stability. In this study, the small porosity of 02m and 0.5m dissipates wind speed and generate less recirculation regions. The design of heliostat must be calculated in-field and the calculation of isolated heliostat wind loads should not be taken as a reference. Also, the presence of well studied fences reduces considerably wind loads on heliostats placed in the front rows.