Design and construction of petal solar reflectors: paraboloid and catenoid

Abstract A detailed geometric study is presented of different designs of solar reflectors based on the methodology of petal diagrams. The paraboloid model is analyzed and a new model is introduced, the catenoid, discussing its advantages and disadvantages on a comparative basis. Conventional and optimized designs are presented for both kinds of surfaces, analyzing quantitatively several critical aspects such as focal distance, effective area and number of petals. Criterions and suggestions are offered to select materials and to plan the size of the system according to its purpose. Some constructed models are presented which evince a good convergence of reflected rays.