Thermosiphon Monitoring Reel for the Fair-Trade Sustainable Hatcheries

In this paper, the thermal performance of cross-corrugated and v-groove solar air collectors has been compared under a wide range of configuration and operating conditions. For cross-corrugated collectors, the air flow channel is formed by the wavelike absorbing plate and the wavelike bottom plate, which are transversely positioned, whereas for v-groove collectors it is formed by the v-groove absorbing plate and the flat bottom plate. The use of the transversely positioned wavelike bottom plate in cross-corrugated collectors is to achieve better thermal performance by enhancing the heat transfer rate inside the air flow channel via augmented turbulence. It is found that cross-corrugated collectors are superior to v‐groove ones for all the configurations and operating conditions considered, confirming that the use of the transversely positioned wavelike bottom plate, in cross-corrugated collectors improves the thermal performance. The results also show that a slender configuration along the air flow direction, a small gap between the absorbing plate and the bottom plate, a selected coating on the absorbing plate and the glass cover that has a very high absorptivity of solar radiation but quite a small emissivity of thermal radiation, an air mass flow rate per unit area of collector above 0.1 kg/m2·s, and maintaining the inlet fluid temperature close to that of the ambient fluid, will lead to improved thermal performance for both collectors. However, it is found that the mean gap between the cover and the absorbing plates, the emissivity of thermal radiation of the bottom plate, the solar insolation, and the inclination of the collectors have negligible effects on the efficiencies of both collectors.

An experimental study is carried out to investigate the heat transfer characteristics of silver/water nanofluid in a solar flatplate collector. The solar radiation heat flux varies between 800 W/m2and 1000W/m2, and the particle concentration varies between 0.01%, 0.03%, and 0.04%. The fluid Reynolds number varies from 5000 to 25000. The influence of radiation heat flux, mass flow rate of nanofluid, inlet temperature into the solar collector, and volume concentration of the particle on the convective heat transfer coefficient and the collector efficiency are studied. Both parameters increase with increase in the particle volume concentration and flow rate. The maximum percentage increase obtained in the convective heat transfer coefficient is 18.4% for the 0.04% volume concentration at a Reynolds number of 25000. An increase in the performance of nanofluid is also witnessed when compared to the base fluid, which has a strong dependency on volume concentration and mass flow rate. MgO. The nanofluid achieved a 3°C temperature difference during the daytime peak solar radiation compared with the base fluids. With a concentration of 0.2% ZnO, a temperature difference of 2.55°C for daytime and 1°C for nighttime was reached, and this was determined to be the most attractive option for solar energy utilization. Yousefi et al. [15] witnessed a 28% performance improvement in a flat-plate collector when it was operated with water-Al2O nanofluids. Tyagi [16] theoretically compared the conventional flat-plate collector with a direct absorption solar collector (DAC) and observed the former to be 10% more efficient. Otanicar [17] studied the conomic and environmental influences of using nanofluids to enhance solar collector efficiency with conventional solar collectors. Dongxiao et al. [18] presented excellent photothermal properties of carbon-black aqueous nanofluids at highvolume fractions. Further work on nanofluids’ application to direct solar absorption has been carried out by Lijuan Mu [19] using a custom-made direct solar absorber. The radiative properties of several nanofluids are tested for the highest temperature difference across the heat exchangers. Based on the above-mentioned review of the literature, it has been clearly observed that most of the previous studies on solar flat-plate collectors were conducted using metal oxide nanoparticles in relatively high concentrations. These high concentrations of metal oxide nanoparticles cause a higher pressure drop that then requires a higher pumping power. Since a limited number of studies exists in the literature with respect to pure metal nanoparticles, it is recommended to study the heat transfer characteristics of pure metal nanoparticles with relatively low concentrations (

Sea background radiation is influenced by solar radiation, sky background radiation and sea surface emission radiation. On the basis of studying the simple sea radiation model, analyze the influence of atmospheric transmittance and sea background radiation to infrared detector, emphasis on influence of solar, sky and sea surface emission radiation to infrared search in analyze Sea background radiation, emphasis on influence of aerosol to infrared search under troposphere in analyze atmospheric transmittance.

This paper discussed the use of solar thermal collector as an input energy for cooling system. The experimental investigation was undertaken to characterize solar collectors that have been integrated with an absorption chiller. About 62 modules of solar collectors connected in series and parallel are placed on the roof top of MRC building. Thermistors were used to measure the fluid temperature at inlet, inside and outlet of each collector, inside the water tank and ambient temperature. Water flow that circulated from the storage was measured by flow meter, while solar radiation was measured by a pyranometer that was mounted parallel to the collector. Experimental data for a data set was collected in March 2016, during the day time hours of 08:00 – 17:00. This data set was used to calculate solar collector efficiency. The results showed that in the maximum solar radiation, the outlet temperature that can be reached is about 78°C, the utilized energy is about 70 kW and solar collector has an efficiency of 64%. While in the minimum solar radiation, the outlet temperature that can be reached is about 53°C, the utilized energy is about 28 kW and solar collector has an efficiency of 43%.

A theoretical approach has been used to evaluate the performance of facade integrated solar collectors based on the physical collector parameters such as absorber plate absorptance, transmittance of the glazed cover plate and insulation thickness. A 1D steady state model, based on the Hottel Whillier Bliss equation, was employed to determine the effect of changing paramete rs to me et facade integration criteria. Buildings account for 40% of the final energy consumption in Europe (1), Over half of this energy use is associated with building heating, cooling and domestic hot water (DHW) demands (2) . This energy is predominantly provided through the burning of fossil fuels, which can be reduced through the implementation of renewable energy systems. Solar thermal systems, for building applications, make use of an area on the building's envelope to install the solar collectors, which in turn, absorb the solar radiation and convert it to useful heat for the building's heating applications. These solar collectors are usually mounted on the roofs of buildings; however, a limited roof area and a high heating load may require the area of the facade to house these collectors (3). Architectural integration barriers can become significant when the facade is used to house the collectors. Solar thermal collectors may be categorised as Unglazed Collectors (UC), glazed Flat Plate Collectors (FPC) or Evacuated Tube Collectors. The FPC is Europe's most popular collector, accounting for 85% of the market share (4). They consist of an absorber plate with a high absorptance and conductivity, insulated at the back using standard insulating wool or foam and insulated at the front through the use of a transparent cover (typically glass) which provides an air gap between the absorber and cover layer. A 1D steady state mathematical model, based on the Hotel Whillier Bliss equation (5), is used to examine the performance of FPC whe re the parameters are altered as appropriate for facade integration.

Solar energy is a form of energy derived from solar radiation. One way to utilize solar energy is to heat water using a solar collector. The solar collector has an absorber plate to heat the water. The absorber is typically in the form of a flat plate, but some use a wave-shaped plate. In previous research, it was found that the shape of the flat plate was better than the shape of the corrugated absorber. This study aimed to determine the most suitable form of absorber for use in solar water heater collectors between two different waveforms. Where the waves are in the form of trapezoids and triangles A solar water heater was made with two different solar collectors. Then the data collection process is carried out, and the data is obtained. The study was conducted over a four-hour period, from 10:00 AM to 2:00 PM. Data collection is carried out every 30 minutes by adding water before heating and removing water after heating. The parameters measured were the inlet and outlet water temperatures, as well as the intensity of sunlight. The solar collector is also positioned at three different angles to determine which angle is most effective for heating solar water. In solar water heating with a triangular absorber shape, an efficiency of 0.65 is obtained, while in a trapezoidal form, an efficiency of 0.74 is obtained. Then, at an angle of 10 degrees, the highest average efficiency for each solar collector ranges from 0.55 to 0.63. Thus, it can be concluded that a solar collector with a trapezoidal absorber shape is more effective than a triangular absorber solar collector at a slope of 10 degrees.

Investigation of the combined efficiency of a solar/gas hybrid water heating system

Solar air collectors have various applications: on the one hand, they can be used for air heating in cold seasons; on the other hand they can be used in summer to evacuate the warm and polluted air from residential, offices, industrial, and commercial buildings. The paper presents experimental results of a solar collector air, under the climatic conditions of the Southeastern Europe. The relationships between the direct solar irradiation, the resulting heat flow, the air velocity at the outlet, the air flow rate, the nominal regime of the collector and the efficiency of conversion of solar energy into thermal energy are all highlighted. Thus, it was shown that after a maximum 50 min, solar air collectors, with baffles and double air passage can reach over 50% efficiency for solar irradiation of 900–1000 W/m2. The article also presents a mathematical model and the results of a computational program that allows sizing solar collectors for the transfer of air, with the purpose of improving the natural ventilation of buildings. The article is completed with case studies, sizing the area to be covered with solar collectors, to ensure ventilation of a house with two floors or for an office building. In addition, the ACH (air change per hour) coefficient was calculated and compared.

One of the methods to improvement of solar-to-thermal energy conversion is the design of geometry in solar collectors. In this paper, the new solar collector which is called solar conical collector has been designed and tested. The efficiency of solar conical collector was experimentally investigated by use of ASHRAE standard. Experiments were performed with water as a working fluid in the outdoor condition of Ahvaz city in the south of Iran. The results show that the average efficiency of a solar conical collector with 1m 2 area of absorber plate and 0.6m diameter of cone is about 53% and it can be used as a useful new water heater.

Solar collector is a thermal device that uses the heated air in the power generation and many engineering applications. The purpose of the present work is to study the performance and temperature distribution for the solar collector which uses heated air in solar chimney power generation that it consist of three parts, a turbine-generator unit which is used in the generation of electric energy, and cylindrical chimney is fixed vertically and finally a solar collector under the climatic conditions of Egypt-Aswan is studied. This site is specified as the hottest site because the nearest of this location from the Tropic of cancer. Experiments are performed in ten summer days of May and June 2015 with different solar radiations and clarity of the sky. Hourly values of global solar radiation and some meteorological data (temperature, pressure, velocity, etc.) for measuring days are obtained by measuring devices. Inlet and outlet temperatures of air from a solar collector and velocity at junction region. In this work, attempt has been made to present the effect of environmental factors such as ambient temperature, the clarity of the sky and solar radiation on the performance of solar collector. The temperature of the base and the cover of the solar collector, the variation of solar radiation, solar collector efficiency, heat transfer coefficient, the velocity at the junction region between the chimney base, the outlet of the solar collector and temperature distribution along the air heater are discussed. A prediction for the results of the solar collector were performed by using developed theoretical model was made by this study which is based on the previous works. The numerical study has used a commercial code CFX, ANSYS 16.1 to simulate the flow through the collector. The study show that the outlet air temperatures from the solar collector and the velocity at the junction are depending on the climate condition such as ambient temperature and solar radiation, the differences in air temperature at the solar collector ranging between 8° - 24°. It is concluded that the theoretical model is basically valid for the system under study, and theCFD simulation can be used conveniently to predict the performance of the system, the comparison between them and experimental result shows a good agreement.

Building sector consumes a greater portion of energy for heating and cooling applications. The utilization of fossil fuels for space and water heating in buildings cause a negative effect on the environment by producing larger CO2. In this study solar thermal water heating system for building application have been analyzed from the first and second law perspectives of thermodynamics considering various scenarios and water consumption pattern. The solar flat collector is very commonly used to extract energy from sunlight. Therefor energy and exergy efficiency curves for the solar flat collector were presented. The energetic and exergetic values for the system were calculated based on the experimental values for the overall system, the heat exchanger and the pumps using the approach of exergetic product/fuel basis. The greatest and lowest relative irreversibility’s occurred at the solar collector and the heat exchanger with values of 85.73% and 2.45%, respectively, and the system overall exergy efficiency was determined to be 20.28%. The energy and exergy efficiencies of the solar collector were analyzed at three different cases depending on the mass flow rates in the solar collector and the secondary circuit of the system. Three different mass flow rates were applied to the inlet of the secondary circuit to observe the efficiency effect on the solar collector circuit. This study can assist in selecting a proper solar collector and storage size for buildings of various capacity and possible improvement in the design of the system components.

This paper studied the effects of tilt angles on the thermal performance of a solar parabolic collector system. This is the angle at which the beam solar radiation arriving from the sun will fall perpendicular to the solar collector surface. The quantitative assessments of radiation incident on a tilted plane are very important for designing solar collecting devices. The idea was to evaluate the thermal performance of the solar collector at the monthly optimal tilt angles in Bauchi (latitude 10°30’ North and 10°00’ East). Monthly mean daily global and diffuse components of the solar radiation for 10 years (January, 2009-December, 2019) were collected and used for the simulation using MATLAB software. Also used for the simulation are the developed energy balance equations for evaluation of thermal performances of solar collector. It was observed that, as the tilt angles decreases, both absorber tube and fluid temperatures together with the thermal efficiencies of the collector increased. Higher tilt angles were witnessed during January-February and September-December (20°-33°) and these months were having low temperatures of the absorber tube and the fluid (169°C-228°C and 130°C-117°C respectively). Low tilt angles between March to August (7°-16°) and with temperatures of the absorber tube and fluid between 220°C-235°C and 128°C-142°C respectively. Maximum thermal efficiency of 73% was obtained at the least optimal tilt angles (7°-8°). Thus, for efficient solar radiation collections, solar parabolic trough collector system should be maintained at optimal tilt angles between 7°-33° in Bauchi depending upon the seasonal variations.

This paper describes an experimental study on efficiency of solar collector in solar water heating system connected to hourly water heating load. In general, the functional form of solar efficiency is expressed as a function of fluid temperature entering solar collector, ambient temperature, and solar irradiance. When energy saving from solar heating of water heating system is analyzed on along-term basis such as one year with given solar irradiance data, simplified analysis is more convenient han detailed system simulation for quick assessment. However, the functional form of the efficiency is not convenient for approximately simplified energy analysis because the inlet temperature can be obtained through a detailed system simulation. In the study, solar collector efficiency is obtained with various daily water heating load sand daily solar irradiance using experimental tests. The study also considers large residential buildings such as apartment buildings for application of solar water heating systems. From test results, it is found that daily solar collector efficiency is proportional to daily water heating loads and daily solar irradiance. The data obtained from the study can be utilized to find a functional relation between daily solar irradiance and daily heating load in stead of collector inlet temperature for application of solar collector efficiency to long-term approximated energy analysis of solar heating system.

Solar air collectors have various applications: on one side, they can be used for air heating in cold seasons; on the other side they can be used in summer to evacuate the warm and polluted air from residential, offices, industrial and commercial buildings. The paper presents experimental results of a solar collector air, in climatic conditions from South Eastern Europe. The relationships between the direct solar irradiation, the heat flow resulted, the air velocity at the outlet, the air flow rate, the time of input in nominal regime of the collector and efficiency of conversion of solar energy into thermal energy are highlighted. Thus, it was shown that after maximum 50 minutes, solar air collectors, with baffles and double pass of air can reach 50 % efficiency for solar irradiation of 900-1000 W/m. 2The article also presents a mathematical model and the results of a computational program that allows sizing solar collectors for the transfer of the air, for their purpose to improve the natural ventilation of buildings. The article is completed with a case study, sizing the area to be covered with solar collectors to ensure ventilation of a house with two floors or for an office building. Also, the ACH coefficient was calculated and compared.

Experimental investigation of an enhanced transpired air solar collector with embodied phase changing materials