Optical evaluation of compound parabolic collector with low acceptance angle

• DOI: 10.1016/j.ijleo.2017.09.039
• Publication Date: 2017-09-11T12:46:17Z
• Authors: Sainath A. Waghmare; Nitin P. Gulhane
• Keywords: Parabolic trough; Acceptance angle; Limiting; Nonimaging optics; Position (finance); Ray; Parabolic reflector

Abstract An optical evaluation improves overall performance of solar collectors by minimizing the optical losses. It includes study and analysis of solar rays and its behavior when falling and reflecting over collectors. As per collector design criteria, the maximum collection of solar rays must concentrate at the receiver. In this research, the optical analyses are performed on compound parabolic collector with low acceptance angle (6°) to optimize the receiver position. In parabolic trough collector (PTC), all the reflected solar rays gather at the focal line, but in CPC the reflected solar rays concentrates in a region on the central plane. This region of concentrated solar rays is determined by 2D graphical ray tracing analysis and it is experimentally verified by camera target method (CTM). The manufacturing error in collector shape is elaborated and error curve is outlined with the help of data points. The ray tracing analysis is performed on the actual and error curve with the incidence angle 0°, +3° and −3°. and it is compared with CTM observations. The results obtained from these methods showed the identical behavior of reflected solar rays and it is concentrated below the limiting diameter at the focus.