Modeling the Performance of a Flat Solar Collector Based on Cellular Polymeric Materials

2021 ◽  
Vol 2 (43) ◽  
pp. 15-19
Author(s):  
Dmitriy S. Strebkov ◽  
◽  
Natal’ya S. Filippchenkova ◽  
Keyword(s):  
Flow Rate ◽  
Solar Collector ◽  
High Efficiency ◽  
Polymeric Materials ◽  
Specific Weight ◽  
Polymer Materials ◽  
Research Purpose ◽  
Solar Collectors ◽  
The Cost ◽  
Cellular Polymer

Currently, in the field of energy supply of agro-industrial facilities, there is an increasing interest in the development of new structures and engineering systems using solar energy, including flat solar collectors based on cellular polymer materials. Modern solar collectors based on metal absorbers, despite their high efficiency, have a large specific weight, high metal consumption and cost. The use of cellular polymer materials for the manufacture of solar collector absorbers reduces the cost and reduces the weight of the installation. (Research purpose) The research purpose is in conducting a numerical simulation of the performance of a flat solar collector based on cellular polymer materials. (Materials and methods) Authors used analytical methods for mathematical modeling of a flat salt collector based on cellular polymer materials. The article presents a mathematical model of a flat solar collector in the computer program ANSYS Fluent. The distribution contours of temperature and pressure of the coolant in the channels of a flat solar collector were obtained at different values of the coolant flow rate at the inlet. (Results and discussion) The article presents comparison the temperature of the coolant at the output of the solar collector on the flow rate of the coolant obtained analytically and using the developed CFD model. The results of verification of the calculated model of the solar collector showed its adequacy and high convergence of the data obtained using the computer model. (Conclusions) The article presents a design of a flat solar collector based on cellular polymer materials. The developed design of a flat solar collector allows us to reduce the specific weight more than three times and reduce the cost while maintaining high thermal performance.

Possibilities of using biodegradable polymeric materials in the agricultural sector

2020 ◽  
Vol 67 (2) ◽  
pp. 115-120
Author(s):  
Raisa A. Alekhina ◽  
Victoriya E. Slavkina ◽  
Yuliya A. Lopatina
Keyword(s):  
Mechanical Properties ◽  
Biodegradable Polymers ◽  
Biodegradable Polymer ◽  
Agricultural Sector ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Limiting Factors ◽  
Research Purpose ◽  
Biodegradable Materials ◽  
Advantages And Disadvantages

The article presents options for recycling polymers. The use of biodegradable materials is promising. This is a special class of polymers that can decompose under aerobic or anaerobic conditions under the action of microorganisms or enzymes forming natural products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts. (Research purpose) The research purpose is in reviewing biodegradable materials that can be used for the manufacture of products used in agriculture. (Materials and methods) The study are based on open information sources containing information about biodegradable materials. Research methods are collecting, studying and comparative analysis of information. (Results and discussion) The article presents the advantages and disadvantages of biodegradable materials, mechanical properties of the main groups of biodegradable polymers. The article provides a summary list of agricultural products that can be made from biodegradable polymer materials. It was found that products from the general group are widely used in agriculture. Authors have found that products from a special group can only be made from biodegradable polymers with a controlled decomposition period in the soil, their use contributes to increasing the productivity of crops. (Conclusions) It was found that biodegradable polymer materials, along with environmental safety, have mechanical properties that allow them producing products that do not carry significant loads during operation. We have shown that the creation of responsible products (machine parts) from biodegradable polymers requires an increase in their strength properties, which is achievable by creating composites based on them. It was found that the technological complexity of their manufacture and high cost are the limiting factors for the widespread use of biodegradable polymers at this stage.

CHANGES IN THE TECHNICAL AND TECHNOLOGICAL LEVEL OF STEAM CULTIVATORS IN THE XXI CENTURY

2021 ◽  
Vol 2 (143) ◽  
pp. 174-183
Author(s):  
Andrey Yu. Nesmiyan ◽  
◽  
Anastasiya S. Kaymakova ◽  
Yuliya S. Tsench ◽  
Keyword(s):  
Weighted Average ◽  
Specific Weight ◽  
Research Purpose ◽  
Utilization Rate ◽  
Average Value ◽  
Technological Level ◽  
Short Test ◽  
Specific Material ◽  
The Cost

Most modern agricultural machines and tools consist of components, the main parameters, design features of which were justified in the first half of the twentieth century. Slowly and evolutionarily, these technical means are developing. (Research purpose) The research purpose is in identifying general trends in the technical and technological level of steam cultivators in the first quarter of the XXI century. (Materials and Methods) For the study there was analyzed the data of the short test reports of the selected machines. The production of steam cultivators in the Russian Federation is gradually increasing. (Results and discussion) For ten years of the beginning of the XXI century, only 27 machines were provided for testing, and from 2014 to 2017 – more than 40, while for "old" cultivators, the weighted average value of the tractor traction class was 2.8, for new ones it is about of four. For the study period (on average 10 years) the quality of soil cultivation in terms of such parameters as deviation from the specified depth of cultivation, crumbling and combing of the field surface has not changed much. The productivity of cultivator units increased by 7-21 percents, which is explained not only by an increase in the power of tractors, but also by an increase in the utilization rate of charge time on average from 0.72 to 0.77. The specific weight of the "new" cultivators was on average 22 kilogram-meters less than that of the "old" analogues, which can be explained by the evolution of their designs. (Conclusions) Increasing the class of tractors by one "level" the specific material consumption of the cultivators aggregated with them increases by about 58 kilogram-meters for both "old" and " new " cultivators. With an increase in the width of the tools from 4 to 16 meters, their weight will increase by 8 times, which affects the cost and operational and environmental characteristics of wide-reach cultivators.

Testing and Analysis of a Heat-Pipe Solar Collector

1983 ◽  
Vol 105 (4) ◽  
pp. 440-445 ◽  
Author(s):  
J. Ribot ◽  
R. D. McConnell
Keyword(s):  
Heat Pipe ◽  
Solar Collector ◽  
High Efficiency ◽  
Heat Pipes ◽  
Solar Collectors ◽  
Empirical Tests ◽  
Heat Transfer System ◽  
Evacuated Tube ◽  
Glass Heat ◽  
Theoretical Analyses

We developed an integral heat-pipe/evacuated-tube solar collector in which the inner receiver tubes form the evaporator sections of glass heat pipes. This paper describes both theoretical analyses and empirical tests, comparing the performance of the glass heat-pipe solar collector with one of today’s high efficiency evacuated-tube solar collectors. The comparison demonstrates that the performance of the two collectors is effectively identical. The testing and analysis indicate that the glass-wick-type glass heat pipe is an effective heat transfer system for evacuated-tube solar collectors.

scholarly journals PROSPECTS OF USING POLYMERIC MATERIALS IN THE CONSTRUCTION OF SOLAR COLLECTORS

2021 ◽  
Vol 2021 (2) ◽  
pp. 58-66
Author(s):  
Volodymyr Labay ◽  
◽  
Bohdan Piznak ◽  
Bogdan Gulai ◽  
Iryna Sukholova ◽  
...  
Keyword(s):  
Solar Energy ◽  
Heat Storage ◽  
Polymeric Materials ◽  
Energy Market ◽  
Solar Collectors ◽  
The Earth ◽  
Solar Thermal Collectors ◽  
Copper Aluminum ◽  
The Cost ◽  
And Storage

The solar energy that reaches the Earth is free, but installations to convert solar energy into heat, as well as equipment for transporting and storage that heat, require some investment. A significant part of the components of these systems are metals. Pipelines in solar collectors and heat exchangers are made of copper, aluminum is used for the absorber and housing, and the steel is often used in heat storage tanks. One of the options to reduce the cost of solar collectors and increase their efficiency is to use polymeric materials instead of metals. The main advantages of using polymeric materials in solar thermal collectors are their cost, especially if you are taking into account the growth of the renewable energy market and rising prices for metal . The use of polymers also reduces the costs of production, transportation and installation for the user.

Experimental and numerical assessments of the effects of vacuum and solar film on the performance of low concentration eccentric solar collector

2021 ◽  
pp. 1-19
Author(s):  
Mavd P. R. Teles ◽  
K.A.R. Ismail
Keyword(s):  
Thermal Performance ◽  
Solar Collector ◽  
High Efficiency ◽  
Numerical Code ◽  
Working Fluid ◽  
Solar Collectors ◽  
Low Concentration ◽  
Lack Of Information ◽  
Collector Efficiency ◽  
Volume Method

Abstract Low concentration collectors are usually recommended for water heating and refrigeration systems. The literature reveals lack of information on numerical modeling, experimental data, and thermal performance of eccentric evacuated double tube solar collectors. This study is focused on eccentric solar collectors since this arrangement allows adequate concentration for achieving relatively high temperatures while having small size and occupying less space. The effects of the vacuum in the annular space and reflective film on the enhancement of working fluid heating and overall thermal performance were also assessed. An in-house numerical code using finite volume method was used to discretize the conservation equations and the predictions were validated by experimental results obtained from an experimental rig that was constructed and instrumented for outdoor tests. The experiments were performed in the city of Campinas-Brazil during the autumn season. The investigated versions of the eccentric double tube solar collector include a version with a reflective film and vacuum, a second version with a reflective film but without vacuum, a third arrangement without a reflective film but with vacuum and finally a version without both a reflective film and vacuum. The results showed that the version with reflective film and vacuum demonstrated high efficiency achieving 89%. The lowest efficiency of 42% was achieved by the version without both reflective film and vacuum. The comparative analysis of the four versions shows that the incorporation of reflective film increases the collector efficiency by 28%, while the vacuum increases the efficiency by about 1.3%.

scholarly journals POLYMERIC MATERIALS FOR SOLAR ENERGY UTILIZATION: A COMPARATIVE EXPERIMENTAL STUDY AND ENVIRONMENTAL ASPECTS

2016 ◽  
Vol 52 (3) ◽  
Author(s):  
Alexander Doroshenko ◽  
Kostyantyn Shestopalov ◽  
Ivan Mladionov ◽  
Vladimir Goncharenko ◽  
Paul Koltun
Keyword(s):  
Experimental Study ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Solar Energy ◽  
Solar Collector ◽  
Polymeric Materials ◽  
Energy Utilization ◽  
Solar Collectors ◽  
Environmental Aspects ◽  
Solar Energy Utilization

Full-scale metal solar collectors and solar collectors fabricated from polymeric materials are studied in present research. Honeycomb multichannel plates made from polycarbonate were chosen to create a polymeric solar collector. Polymeric collector is 67.8% lighter than metal solar collector. It was experimentally shown that the efficiency of a polymeric collector is 7–14% lower than a traditional collector. An ecologically based Life Cycle Assessment showed the advantages of the application of polymeric materials in the construction of solar collectors.

scholarly journals The effect of the intermediate fluid flow rate on the system performance in the closed circuit applications of the solar collector

2019 ◽  
pp. 472-472 ◽  
Author(s):  
Hasan Yildizhan ◽  
Taqi Cheema ◽  
Mecit Sivrioğlu
Keyword(s):  
Heat Transfer ◽  
Fluid Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Closed Loop ◽  
Closed Circuit ◽  
Working Fluid ◽  
Solar Collectors ◽  
Flow Rates ◽  
Energy And Exergy

Solar collector water heating system use solar thermal energy to provide hot water for domestic and industrial use. These systems are operated either as open-loop or closed-loop flow circuit. The former loop systems are not recommended for the cold climates having water freezing problem. Although previous studies on solar collectors have used closed-loop operation with water as the working fluid; however, it must have high boiling and low freezing points for the colder regions and thus arises the need for antifreeze mixtures of water. Another solution to the same problem is the use of heat transfer oil as intermediate working fluids. In the present study, the energy and exergy analysis of a boiler supported vacuum tube solar collector system working with closed-loop in different working fluid flow rates have been performed and evaluated. Heat transfer oil has been used as an intermediate working fluid in the closed loop system at different flow rates of 0.277 kg/s, 0.383 kg/s, 0.494 kg/s. The results show that the collector temperature difference as well as the outlet temperature decrease; however, the collector inlet temperature increases by increasing the flow rate. Moreover, with the increase in flow rate, it was ascertained that the energy and exergy efficiency of the system and the collectors increase. The main finding of the present study is that the intermediate fluid used in the closed-circuit operation of the solar collectors has a direct effect on the energy and exergy efficiency of the system.

BIO-FUEL PRODUCTION FROM CARBONDIOXIDE GAS USING S. elongatus PCC 7942 FROM CYANOBACTERIA

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Delia Teresa Sponza ◽  
Cansu Doğanx
Keyword(s):  
Flow Rate ◽  
Maximum Yield ◽  
Butanol Production ◽  
Fuel Production ◽  
Cost Analyses ◽  
Operational Conditions ◽  
O2 Concentration ◽  
The Cost ◽  
Pcc 7942 ◽  
Dissolved O2

The scope of this study, is  1-butanol production from CO2 with S. elongatus PCC 7942 culture. The yields of 1-butanolproduced/CO2utilized have been calculated. The maximum concentration of produced 1- butanol is 35.37 mg/L and 1-butanolproduced/CO2utilized efficiency is 92.4. The optimum operational conditions were  30°C temperature, 60 W intensity of light, pH= 7.1, 120 mV redox potential, 0.083 m3/sn flow rate with CO2 and 0.5 mg/l dissolved O2 concentration. Among the enzymes on the metabolic trail of the production of 1-butanol via using S. elongatus PCC 7942 cyanobacteria. At maximum yield; the measured concentrations are 0.016 µg/ml for hbd; 0.0022 µg/ml for Ter and 0.0048 µg/ml for AdhE2. The cost analyses necessary for 1-butanol production has been done and the cost of 1 litre 1-butanol has been determined as maximum 1.31 TL/L.

Automated Control of the Microclimate in the Premises of Pig-Breeding Complexes

2020 ◽  
pp. 103-108
Author(s):  
Viktoriya Yu. Ukhanova
Keyword(s):  
Agricultural Production ◽  
Individual Characteristics ◽  
Feed Consumption ◽  
Management Systems ◽  
Research Purpose ◽  
Energy Costs ◽  
Technical Equipment ◽  
Pig Farming ◽  
The Individual ◽  
The Cost

In the pig breeding, a large share of the production cost is accounted for by the cost of electricity and heat. Reducing energy costs is one of the important tasks of the industry. It is important to identify and study modern technologies and equipment for pig farming due to the constant increase in electricity tariffs, significant energy costs for creating and maintaining a microclimate. (Research purpose) The research purpose is in an analysis of modern available technologies and equipment for agricultural production, including pig farming, allowing to reduce the cost of production. (Materials and methods) Authors used a method for determining the standard indicators of energy consumption of energy resources in the pig industry, based on the calculation and analytical method. The article presents an analyze of automated microclimate management systems in pig breeding complexes, taking into account the individual characteristics of farms produced by OWEN. (Results and discussion) Automated microclimate management systems can improve the productivity of pig farms; reduce the cost of electrical and thermal energy, reduce the number of diseases of animal from hypothermia, high humidity or temperature in the room, feed consumption; monitor the chemical composition of the air. The article considers three options for creating a microclimate in rooms with animals, taking into account the individual characteristics of enterprises. (Conclusions) The profitability of pig production depend on the level of technical equipment of farms, automation, and the use of energy-saving technologies and equipment. The use of innovations in agricultural production makes it possible to increase labor productivity up to three times, and savings due to reduced feed costs can reach several million rubles a year.

Microcontroller Device for Conductor Identification Using Acoustic Signal

2020 ◽  
Vol 67 (1) ◽  
pp. 28-34
Author(s):  
Aleksandr V. Vinogradov ◽  
Aleksey V. Bukreev
Keyword(s):  
Acoustic Signal ◽  
Acoustic Waves ◽  
Theoretical Calculations ◽  
Poor Quality ◽  
Electrical Circuit ◽  
Research Purpose ◽  
Electrical Wiring ◽  
The Right ◽  
The Cost ◽  
Technical Solutions

When repairing and replacing electrical wiring in enterprises, the main difficulty is the lack or poor quality of documentation, plans for conductors laying. Distinguishing wires (cables) and their cores by the color of the shells or using tags attached to the ends is difficult if the shells have the same color and there are no tags. Devices and technical solutions used to identify wires and cables do not allow recognizing conductors without breaking the electrical circuit, removing insulation, and de-energizing the network. Searching for the right conductor is a time-consuming operation. (Research purpose) The research purpose is developing a new microcontroller device for identifying wires using an acoustic signal. (Materials and methods) Literature sources has been searched for devices for conductors identifying. (Results and discussion) The article proposes a method that involves feeding an acoustic signal to a wire at one point and capturing it at another, in order to recognize the desired wire. The article presents results of comparison of the developed microcontroller device for identifying conductors using an acoustic signal with known devices and methods for conductors recognizing. (Conclusions) The article reveals the shortcomings of existing methods and means of identifying wires and cables. Authors performed a theoretical calculation of the sound pressure in the conductor at a given distance. The article presents the calculation of speed of acoustic waves in conductors with different types of insulation. Authors designed a microcontroller device for identifying conductors using an acoustic signal and tested it. It was determined that the device increases the safety of work, reduces the cost of operating internal wiring and identification time; eliminates the violation of wire insulation, the need to disable electrical receivers. The convergence of theoretical calculations and experimental data was shown.

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