@ARTICLE{Zapałowicz_Zbigniew_Estimation_2021, author={Zapałowicz, Zbigniew and Garnysz-Rachtan, Agnieszka}, volume={vol. 42}, number={No 1}, pages={129-146}, journal={Archives of Thermodynamics}, howpublished={online}, year={2021}, publisher={The Committee of Thermodynamics and Combustion of the Polish Academy of Sciences and The Institute of Fluid-Flow Machinery Polish Academy of Sciences}, abstract={Application of retractable enclosures enables to lengthen operation periods for outdoor swimming pools operated in the moderate climate zone. Enclosures allow to diminish energy losses from water in the pool to the environment. Thermal calculations for pools with retractable enclosures are difficult to carry out because of a number of required parameters which can only be estimated. One of them is the transmission of solar radiation through the enclosure. The present paper presents the method of estimation of this parameter for swimming pool enclosures made of polycarbonate panels that have multichannels structure. In order to calculate transmission, the methodology considering the multiples of solar reflection inside the enclosure and their absorption by polycarbonate has been elaborated. Calculation results for transmission of the enclosure were verified experimentally. Analysis of results show that the transmission depends strongly on the enclosure’s construction and on the direction of solar radiation on the enclosure. Mean transmission values of enclosure under research were determined both from calculations and experiment are equal to about 0.69 and 0.64, respectively. However, experimentally determined mean values of total transmission by parallel and perpendicular solar directions in relation to channel axes are equal to about 0.69 and 0.60, respectively.}, type={Article}, title={Estimation of solar radiation transmission for polycarbonate retractable swimming poolen closures}, URL={http://journals.pan.pl/Content/119572/art08.pdf}, doi={10.24425/ather.2021.136951}, keywords={Outdoor swimming pool, Swimming pool roofing system, Pool enclosure, Polycarbonate enclosure, Solar transmission through enclosure}, }