UC Merced

The objective of this thesis is to perform a preliminary optical assessment of the external compound parabolic concentrator (XCPC) component in three concentrating solar thermal units. Each solar thermal unit consists an optical element (the non-imaging concentrating reflector) and a thermal element (the evacuated glass tube solar absorber). The three concentrating solar thermal units discussed in this work are DEWAR 58, a direct flow all-glass dewar, DEWAR 47 an indirect flow all-glass dewar filled with thermal fluid and JIANG TUBE, a metal absorber with glass-to-metal seal. From the performance results, we will be able to determine the optical efficiency of the XCPC reflectors as well as the concentration ratio for radiation being transferred from the sun onto each of the three solar thermal collectors.