Numerical Study and Optimization of Mirror Gap Effect on Wind Load on Parabolic Trough Solar Collectors

Parabolic trough collector (PTC) technology is currently the most proven and widely used solar thermal electric technology. These systems are usually located in open terrain where strong winds may occur and affect their stability and opticalperformance. As tiny deformation of collectorsunder the action of strong wind will influence the focusing accuracyandincrease the structure demands of the collectors, it leads to the increase of the cost of collectors.It is particularly important to study the effect of wind load on parabolic trough solar collectors. In this context, different axial and radial gap sizes (0-0.06m)between the mirrors of PTCon wind load were studied numerically based on computationalfluid dynamics (CFD). Wind load on collectors is decreased by around 13% with the axial gap extending from 0 to 0.06mwhile the effect of radial gap on wind load is small.Furthermore, the optimization model between the wind load and mirror gap was obtained by response surface methodology (RSM). The optimal gap size within 0m to 0.06m for a parabolic trough solar collector waspredicted byparticle swarm optimization (PSO). The result shows theoptimum axial gap is 0.06m and the optimum radial gap is 0.02m.