– 942 – Journal of Siberian Federal University. Engineering & Technologies 2021 14(8): 942–949 ~ ~ ~ Theoretical and Applied Heating Engineering Теоретическая и прикладная теплотехника DOI: 10.17516/1999-494X-0364 УДК 621.311.243 Issues of Development of Solar Collectors with High Effciency Mirsoli O. Uzbekov* and Bekzod B. Boynazarov Fergana Polytechnic Institute Republic of Uzbekistan, Fergana Received 14.09.2021, received in revised form 21.10.2021, accepted 21.11.2021 Abstract. The article deals with the creation of energy-effcient solar water collectors. In order to develop energy-effcient solar water collectors (SWC), methods of rational enhancement of heat transfer in the channels of the collectors are proposed. It is noted that the methods used to increase heat transfer from the collector walls to the water should be tailored to a low-speed fow of the heat carrier. With such fow regimes, the most acceptable ways to enhance heat transfer are: fow swirling, the use of artifcial roughness, renewal of the hydrodynamic boundary layer through the creation of an alternating pressure gradient in the fow. The analysis of the conducted research shows that the maximum effects of increasing heat transfer occur in the range of Re numbers from 2000 to 8000, i. e. in the laminar fow region and in the region of underdeveloped turbulence. An effciency criterion is obtained for the conditions under which enhancers are installed inside the pipes. The criterion determines the ratio of the number of pipes with enhancers to the number of smooth pipes. The calculation is carried out for cases in which the heating capacity, fow rate, power for heat carrier circulation and the pipe diameter of the SWC with smooth pipes are equal to the heating capacity, fow rate, power for heat carrier circulation and pipe diameter of the SWC with the pipes with enhancers. In addition to the specifed effciency criterion of the SWC, a heat transfer comparison formula of the SWC having pipes with enhancers and SWC with smooth pipes is obtained. Keywords: solar water collectors, effciency, heat transfer, heat engineering, convection, solar engineering. Citation: Uzbekov M. O., Boynazarov B. B. Issues of development of solar collectors with high effciency, J. Sib. Fed. Univ. Eng. & Technol., 2021, 14(8), 942–949. DOI: 10.17516/1999-494X-0364 © Siberian Federal University. All rights reserved This work is licensed under a Creative Commons Attribution-Non Commercial 4.0 International License (CC BY-NC 4.0). * Corresponding author E-mail address: m.uzbekov@ferpi.uz