Modifications to straight-walled trapezoidal groove solar energy collectors

This thesis presents the results of a comparative study of the radiative performance of several families of solar energy collectors consisting of East-West aligned grooves. The energy is collected at the base of the groove; the sidewalls are reflectors. Interest is centered on the effect of wall curvature on the radiative performance (concentration ratio) of the groove. A ray-tracing computer simulation, which has been developed, accepts up to a sixth-degree polynomial for the wall. Solar absorptivity, as well as the degree of specularity of the wall, are accounted for in the simulation. It is first demonstrated that the wall curvature can increase the concentration ratio above that obtainable with a similar (same depth and opening) straight-walled groove. Then "easily obtainable" (in a manufacturing sense) wall geometries are considered. Their performance is compared to the straight-walled groove and to other groove-like collectors.