Solar Thermal Energy Installations
Laboratory Solar Thermal and Power Plants was founded in 1975 by a doctor of technical sciences, professor RR Avezov as part of the Physical Technical Institute (FTI) of the Academy of Sciences of the Republic of Uzbekistan. in the city of Tashkent.
The main direction of scientific research is the development, optimization of thermal characteristics and the creation of prototypes of low-potential solar thermal installations and heat supply systems based on them; development, improvement and optimization of the basic parameters of insolation passive solar heating systems, adapted to the climatic conditions of Uzbekistan; development and circuit-thermal optimization of parameters of solar-fuel heating plants for individual and collective consumers; development and creation of solar water desalination plants; development and thermal optimization of solar greenhouses parameters with heat accumulation; exergic analysis of the efficiency of solar thermal power plants; the study of the thermophysical properties of phase transition materials for use in solar thermal installations as a heat accumulator; studies of the thermophysical properties of nanofluids for use in solar converters as a coolant, etc.
Over the past 10 years, laboratory staff completed 10 projects: 2 fundamental, 6 applied (including 2 youth) and 2 innovative projects. The main research projects carried out in the framework of fundamental projects consist in the development of the theoretical foundations of the thermal conversion of solar radiation energy. The studies, within the framework of applied and innovative projects, are aimed at developing efficient solar thermal plants for various purposes, developing innovative and new technical solutions for implementation in various sectors of the economy of Uzbekistan.
The laboratory carries out the following research projects:
1. The project of basic research F3-FA-O-50940 on the topic: "Investigation of the thermal engineering and dynamic characteristics of the insolation systems of solar heating and thermodynamic converters of solar energy." Scientific adviser Ph.D., vn.s. N.P. Avezov;
2. Scientific and technical project FA-A4-F030 on the topic: "Development and implementation of an express thermal test method and determination of the main thermal parameters of flat solar collectors and absorbers for heating a heat-transfer fluid." Scientific adviser Ph.D., vn.s. N.P. Avezov;
3. Innovative project FA-I4-F003 on the topic: “Creation and commissioning of solar heat supply and air-conditioning systems of the administrative and household building of OOO OOO Tashelektromash”. Scientific adviser Ph.D., vn.s. Avezova N.P.
4. Scientific and technical project FA-A4-F023 on the topic: "Development of an automated system for controlling a heliostatic field." Scientific adviser Ph.D., Senior Researcher ZH.S. Akhatov;
5. International Uzbek-Chinese project: “Heat transfer fluid”. (Joint Project: Uzbekistan-China) ”. Scientific adviser Ph.D., Senior Researcher ZH.S. Akhatov;
6. Investigation of the thermal performance of phase transition thermal accumulators in low-temperature solar installations. Scientific adviser E.T. Zhuraev.
The following main results were obtained:
Fundamental research
Completed research on the development of theoretical and practical bases of thermal calculation of flat solar collectors for heating the heat-transfer fluid. According to the results of these studies, the calculated expressions were first obtained for determining the mass-average temperature of the coolant in the heat-removing channels of the radiation-absorbing collector panels of the type considered; thermal efficiency coefficient; their average surface temperature is the effective reduced heat loss coefficient of radiation-absorbing collector panels to the environment, in which (unlike studies by foreign scientists) partial absorption and conversion of solar radiation passing through the translucent body cover of the considered collectors are taken into account. Based on the implementation of the obtained theoretical results, in the practice of heat consumption of solar water-heating collectors, their thermal model was created for the first time, which allows determining their heat output, depending on the preset temperature value of hot water produced from them; the specific annual heat output has been established; technical, economic and environmental indicators of solar water-heating collectors, at temperatures of hot water from 35 to 60 ° C. Based on the implementation of the results of completed basic research, a conceptual scheme of the test bench for thermal testing of solar water heating collectors has been proposed, a method and procedure for conducting short-term thermal tests using it have been developed, which can significantly (4 ÷ 5 times) reduce material and financial costs and test periods.
The regularity of the processes of thermal conversion and the use of solar energy in insolation passive heating systems with multifunctional energy-active three-layer translucent fences is studied. The scientific bases for forecasting and regulating the temperature regime of the air environment of a heated room were developed using the considered systems. The mechanism of formation of the processes of natural heat accumulation in the inner layers of massive room fences heated with the systems under consideration has been studied and the necessary amount of short-term accumulator of daytime excess heat of solar radiation from low-temperature phase transition materials has been determined. The heat and hydraulic characteristics of multifunctional three-layer energy-active translucent fences with ventilated air gaps and partially radiation absorbing laminate coatings made of thin polymer films were studied. Based on the implementation of the results of basic research in this area, it has been established that the use of multifunctional energy-active translucent fencing in insolating passive heating systems allows increasing the efficiency of solar energy use by 5 ÷ 10% (compared to traditional) and significantly reducing the summer heat gain to the room through it light making.
Applied research
A method has been developed for calculating the productivity, thermal efficiency and utilization rate of the primary heat of a solar water desalination plant with a multi-stage evaporation-condensation chamber (MIC). A prototype of a solar water-desalination plant with a MIC has been designed and manufactured. It is shown that due to the recuperative use of the heat of condensation in solar desalination plants with a MIC, the productivity can be increased up to two times (6-7l per day), as compared with the usual greenhouse desalination plant (up to 3l per day).
A solar water desalination plant has been developed, which works on the basis of the method of reverse osmosis of salt water purification, with a capacity of 100 liters. in a day. Created a prototype of the installation and conducted tests in natural conditions. As the test results during the year showed, the installation in question is one of the economically and technically beneficial systems for use as an autonomous system of drinking water supply for remote consumers of the Republic. The prototype of the installation consists of a 30W solar panel and a rechargeable battery (24V, 8A h), a booster pump (24V, 0.6A), and a five-step reverse osmotic system for salt water purification.
Innovative research
According to the results of completed studies, for the first time (in the administrative building of the PP LLC Electromash), on the example of the development, creation and synthesis of operating experience of a solar hot water system, an insolation passive and panel radiant solar heating system and an air conditioning system, based on one two-stage evaporative air cooling and rotating heat regenerators, the possibility of a significant expansion of the use of combined solar heat power systems has been proved supply and air conditioning without the use of chillers that provide savings of traditional energy resources to 50% or more.
The design was developed, the corresponding geometrical, optical and heat engineering parameters were optimized, a solar complex for growing and drying agricultural products, with a total area of 100m2, was created and put into operation in the Bukhara region. With the help of this complex, in the flight mode, there is the possibility of drying 1.0-1.5 tons of agricultural products (vegetables, fruits, etc.) in one run, and during the year, given the duration of the cycles, depending on the type of product, 10-12 tons of agricultural products can be dried. The complex includes a 3 kW low-power photovoltaic station, which ensures autonomous operation of the ventilation and lighting system of the complex and additional rooms designed for processing and storing products. The complex, on a daily basis, produces an average of 2kWh of electrical energy (using FES) and about 300 kWh of thermal energy. Due to the use of this complex, you can save 2 kWh of electrical energy and 40-45 m3 of natural gas daily.
The laboratory staff maintains close ties with leading research centers in Russia, Germany, Italy, Spain, Greece, Israel, the People's Republic of China, etc., and actively participate in international scientific conferences.
Over the past 10 years, 120 publications have been published in this direction, 98 of them abroad, in prestigious scientific journals, and 21 patents have been obtained.