Investigation of a Compound Parabolic Collector with a Flat Glazing

The compound parabolic concentrator is a promising technology for efficient solar irradiation exploitation at low- and medium-temperature levels. This collector type can be used in a series of applications, such as solar cooling, desalination, and industrial process heat applications. This work presents a novel compound parabolic concentrator that presents satisfying efficiency and low cost due to the use of flat glazing and not an evacuated tube receiver. More specifically, the goal of the present investigation is based on the energy and exergy analysis of a compound parabolic collector with flat glazing, which has a concentration ratio of 2.81. The collector is examined thermally and exegetically, aiming to calculate the efficiency of different operating inlet temperatures. Moreover, the solar unit is studied by a developed computational fluid dynamics model in the SolidWorks Flow Simulation tool. Emphasis is given to the calculation of the convection losses of the receiver tube with the internal air inside the collector. The heat convection coefficient is calculated, and the distribution of the thermal losses, convection, and radiation is presented. Furthermore, the temperature levels of the absorber, the cover glass, and the top thermal loss coefficient are found. The thermal efficiency of the solar unit was 77.4% for inlet temperature at 10 degrees C and 32.6% for inlet temperature at 110 degrees C. It was calculated that the maximum exergetic performance of the solar unit is 10.19% for operation at 90 degrees C, while the thermal efficiency for this case is 41.57%. Additionally, the temperature distributions for different cases are included in the present work.

Automated summary

The study proposes a novel compound parabolic concentrator with flat glazing, which achieves satisfactory efficiency and low cost compared to the traditional evacuated tube receiver. Energy and exergy analysis are conducted on a collector with a concentration ratio of 2.81, and the thermal efficiency at different operating inlet temperatures is calculated. The study also includes a computational fluid dynamics simulation using SolidWorks Flow Simulation to analyze the convection losses of the receiver tube.