DESIGN OF A MULTIPLE-LAMP LARGE-SCALE SOLAR SIMULATOR

A simple solution to the conflicting constraints of providing uniformi ty and collimation of irradiance in multiple-lamp solar simulators is proposed. As proof of concept, irradiance measurements obtained in a s imulator comprised of 28 1-kW mercury-iodide gas discharge lamps and c apable of irradiating a 1.22 m-by-2.44 m collector plane are given. Th e design is based on preventing a portion of the light from each bulb from reaching the collector plane. Light blockage is achieved by placi ng a ''shadow board'' 1.02 m from and parallel to the plane of the lam ps. Lamps are arranged in an hexagonal pattern with 4 columns of 7 lam ps at a lamp-to-lamp spacing and column-to-column spacing of 0.45 m. L amp-to-collector plane distance is 3.05 m. The design is determined fr om measurements of the spatial distribution of radiant energy from a s ingle lamp. Irradiance from an array of lamps is then simulated. Measu rements of irradiance in the full-scale simulator confirm that uniform ity and collimation conform to the American Society of Heating, Refrig erating and Air Conditioning Engineers' standard. Average irradiance i s 1080 W/m2. Maximum irradiance is 1190 W/m2 and minimum irradiance is 980 W/m2. Every point on the plane of the collector receives 100 perc ent of radiant energy from an area on the lamp array contained within a subtended angle of 20 deg.