The prospects of polymeric materials in assembling the solar water-thermal collectors. Comparative data analysis and exploratory research of promising solutions

Abstract

Concerning the construction of a solar water-thermal collector – the analysis of the applied polymeric materials has been performed in relation to manufacturing of its main parts – the heat absorber and the transparent cover. The use of polymers in the construction of the solar water-thermal collector allows one to lower the manufacturing costs, make the collector light-weight and reduce its price. An analytical review based on the domestic and foreign research and development, published in scientific journals over the past few years, which the authors hope shall be a useful reading in the design-engineering departments responsible for constructing the polymeric solar collectors is the goal of the present work, along with the comparative analysis provided further on the collectors’ efficiency for making a choice of material and the solar energy capture systems’ testing methodology. As the fundamental direction of further improvement of the polymeric solar collectors, the authors aim at: elimination of the air gap between the heat absorber and the transparent cover, leading to construction of a monoblock solar collector; optimization of the heat absorber’s and the transparent cover’s flow channels in solar water-thermal collectors, which concern their compages as well as the size and geometry of the hydraulic collector; optimization of the transparent cover’s channels size as the means of air circulation, which lowers summary heat losses in solar water-thermal collectors; studying the evenness of the heating agent’s distribution in the heat absorber’s channels out in the field, to pursue the improvements in efficiency of the solar water-thermal collectors, and to avoid the heat shock of a solar water-thermal collector’s structural elements upon uneven warming-up. In the present work the analysis has been performed on the summary heat losses (convective and radiation losses realized from the solar collector’s heated-up elements) which depend on a polymeric solar collector’s operating conditions and geometrics as well as on a solar energy capture system’s external environment; a tryout facility has been built, affording a comparative analysis of various solutions; and the main objectives of further research in the field of polymeric solar collectors, particularly, the questions on improvement of their assembly realisation, and reliability of multifunctional solar energy capture systems have been formulated.