WorldWideScience

Sample records for plate collectors water

  1. Flat plate collector. Solarflachkollektor

    Energy Technology Data Exchange (ETDEWEB)

    Raab, N

    1979-03-29

    The invention refers to a flat solar collector with an absorber plate, which is arranged on a support and is covered by a transparent window, between which and the plate there is an air space. The previously known structures of this type had the disadvantage that the thermal expansion of the enclosed air caused considerable difficulties. The purpose of the invention is therefore to create a collector, which can be used on the modular system, retains its properties and is safe in spite of the great temperature variations. According to the invention this problem is solved by providing a compensating space in the collector, which is separated by a diaphragm from the airspace between the plate and the covering window. The airspace therefore remains sealed against the atmosphere, so that no dirt, corrosion of the inside and no condensation can reduce the efficiency of the collector. A rise in pressure due to an increase in temperature is immediately reduced by expansion of the diaphragm, which enters the compensation space. In order to increase the pressure in the airspace above the plate for increases in temperature, the compensation space is connected to the atmosphere. The diaphragm can be mirrored on the side towards the absorber, which makes the diaphragm into an insulating element, as it reflects radiated heat from the absorber.

  2. THERMAL PERFORMANCE OF FLAT PLATE SOLAR COLLECTOR

    Directory of Open Access Journals (Sweden)

    TABET I.

    2017-06-01

    Full Text Available In this paper, a theoretical and experimental studyof flat platesolar water collector with reflectors.A mathematical model based on energy balance equations saw the thermal behavior of the collector is investigated. The experimental test was made at the unit research applies in renewable energy (URAER located in southern Algeria.An increase of 23% for solar radiation incident on the collector surface with the addition of the planers reflectors in the day of May, this increase causes an improvement of the performance of the collector,the fluid temperature increases with an average of 5%. Thetests conducted on the flat plate solar water collector in open circuit enabled the determination of thermal performance of the collector by estimating the daily output The thermal efficiency of the collector ranges from 1% -63% during the day, a mean value of 36%obtained.

  3. Numerical study on the effects of absorptivity on performance of flat plate solar collector of a water heater

    Science.gov (United States)

    Tambunan, D. R. S.; Sibagariang, Y. P.; Ambarita, H.; Napitupulu, F. H.; Kawai, H.

    2018-03-01

    The characteristics of absorber plate of a flat plate solar collector play an important role in the improvement of the performance. In this work, a numerical analysis is carried out to explore the effect of absorptivity and emissivity of absorber plate to the performance of the solar collector of a solar water heater. For a results comparison, a simple a simple solar box cooker with absorber area of 0.835 m × 0.835 m is designed and fabricated. It is employed to heat water in a container by exposing to the solar radiation in Medan city of Indonesia. The transient governing equations are developed. The governing equations are discretized and solved using the forward time step marching technique. The results reveal that the experimental and numerical results show good agreement. The absorptivity of the plate absorber and emissivity of the glass cover strongly affect the performance of the solar collector.

  4. Flat plate solar collector for water pre-heating using concentrated solar power (CSP)

    Science.gov (United States)

    Peris, Leonard Sunny; Shekh, Md. Al Amin; Sarker, Imran

    2017-12-01

    Numerous attempt and experimental conduction on different methods to harness energy from renewable sources are being conducted. This study is a contribution to the purpose of harnessing solar energy as a renewable source by using flat plate solar collector medium to preheat water. Basic theory of solar radiation and heat convection in water (working fluid) has been combined with heat conduction process by using copper tubes and aluminum absorber plate in a closed conduit, covered with a glazed through glass medium. By this experimental conduction, a temperature elevation of 35°C in 10 minutes duration which is of 61.58% efficiency range (maximum) has been achieved. The obtained data and experimental findings are validated with the theoretical formulation and an experimental demonstration model. A cost effective and simple form of heat energy extraction method for space heating/power generation has been thoroughly discussed with possible industrial implementation possibilities. Under-developed and developing countries can take this work as an illustration for renewable energy utilization for sustainable energy prospect. Also a full structure based data to derive concentrated solar energy in any geographical location of Bangladesh has been outlined in this study. These research findings can contribute to a large extent for setting up any solar based power plant in Bangladesh irrespective of its installation type.

  5. Thermal analysis and performance optimization of a solar water heater flat plate collector: Application to Tetouan (Morocco)

    International Nuclear Information System (INIS)

    Dagdougui, Hanane; Ouammi, Ahmed; Robba, Michela; Sacile, Roberto

    2011-01-01

    The development of sustainable energy services like the supply of heating water may face a trade-off with a comfortable quality of life, especially in the winter season where suitable strategies to deliver an effective service are required. This paper investigates the heat transfer process as well as the thermal behavior of a flat plate collector evaluating different cover configurations. This investigation is performed according to a two-folded approach. Firstly, a complete model is formulated and implemented taking into account various modes of heat transfer in the collector. The goal is to investigate the impact of the number and types of covers on the top heat loss and the related thermal performance in order to support decision makers about the most cost-effective design. The proposed model can also be used to investigate the effect of the different parameters which may affect the performance of the collector. Secondly, a two objective constrained optimization model has been formulated and implemented to evaluate the optimality of different design approaches. The goal is to support decision makers in the definition of the optimal water flow and of the optimal collector flat area in order to give a good compromise between the collector efficiency and the output water temperature. The overall methodology has been tested on environmental data (temperature and irradiation) which are characteristic of Tetouan (Morocco). (author)

  6. Heat transfer performance of silver/water nanofluid in a solar flat-plate collector

    OpenAIRE

    Lazarus, Godson; Roy, Siddharth; Kunhappan, Deepak; Cephas, Enoch; Wongwises, Somchai

    2015-01-01

    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 con...

  7. Bioinspired plate-based fog collectors.

    Science.gov (United States)

    Heng, Xin; Luo, Cheng

    2014-09-24

    In a recent work, we explored the feeding mechanism of a shorebird to transport liquid drops by repeatedly opening and closing its beak. In this work, we apply the corresponding results to develop a new artificial fog collector. The collector includes two nonparallel plates. It has three advantages in comparison with existing artificial collectors: (i) easy fabrication, (ii) simple design to scale up, and (iii) active transport of condensed water drops. Two collectors have been built. A small one with dimensions of 4.2 × 2.1 × 0.05 cm(3) (length × width × thickness) was first built and tested to examine (i) the time evolution of condensed drop sizes and (ii) the collection processes and efficiencies on the glass, SiO2, and SU-8 plates. Under similar experimental conditions, the amount of water collected per unit area on the small collector is about 9.0, 4.7, and 3.7 times, respectively, as much as the ones reported for beetles, grasses, and metal wires, and the total amount of water collected is around 33, 18, and 15 times. On the basis of the understanding gained from the tests on the small collector, a large collector with dimensions of 26 × 10 × 0.2 cm(3) was further built and tested, which was capable of collecting 15.8 mL of water during a period of 36 min. The amount of water collected, when it is scaled from 36 to 120 min, is about 878, 479, or 405 times more than what was collected by individual beetles, grasses, or metal wires.

  8. SIMULATION OF SOLAR LITHIUM BROMIDE–WATER ABSORPTION COOLING SYSTEM WITH DOUBLE GLAZED FLAT PLATE COLLECTOR FOR ADRAR

    Directory of Open Access Journals (Sweden)

    ML CHOUGUI

    2014-12-01

    Full Text Available Adrar is a city in the Sahara desert, in southern Algeria known for its hot and dry climate, where a huge amount of energy is used for air conditioning. The aim of this research is to simulate a single effect lithium bromide–water absorption chiller coupled to a double-glazed flat plate collector to supply the cooling loads for a house of 200m2 in Adrar. The thermal energy is stored in an insulated thermal storage tank. The system was designed to cover a cooling load of 10.39KW for design day of July. Thermodynamic model was established to simulate the absorption cycle. The results have shown that the collector mass flow rate has a negligible effect on the minimum required collector area, but it has a significant effect on the optimum capacity of the storage tank. The minimum required collector area was about 65.3 m2, which could supply the cooling loads for the sunshine hours of the design day for July. The operation of the system has also been considered after sunset by saving solar energy.

  9. Performance augmentation in flat plate solar collector using MgO/water nanofluid

    International Nuclear Information System (INIS)

    Verma, Sujit Kumar; Tiwari, Arun Kumar; Chauhan, Durg Singh

    2016-01-01

    Highlights: • Use of nanofluid improves the performance of solar collector. • Thermo-physical properties of the nanofluid have been discussed. • Optimum particle concentrations are found to exist. • Bejan number reaches closer to unity. - Abstract: In present work, testing of solar collector has been performed for MgO/water working fluid having particle size ∼40 nm and particle volume concentration at 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5% at 0.5, 1.0, 1.5, 2.0, 2.5 lpm respectively. Performance analysis of solar collector is based on first law of energy balance and qualitative nature of energy flow based on second law analysis. Parameters of performance analysis are chosen in order to examine both quantitative and qualitative characteristics of system performance. These parameters are thermal efficiency, energetic efficiency, pumping power, entropy generation; Bejan number and reduction in surface area. Experimental observation establishes thermal efficiency enhancement 9.34% for 0.75% particle volume concentration at flow rate 1.5 lpm. Exergetic efficiency enhancement observed 32.23% for same concentration and flow rate. Bejan number also reaches closer to unity (0.97) which throws light on systems qualitative response in terms of decline in entropy generation contribution due to internal irreversibilities and frictional heat loss. Entropy generation is 0.0611 W/K for 0.75% particle concentration compare to 0.1394 W/K for same flow rate and 0.071 W/K for 1.5% particle volume concentration. In this endeavor some penalty in form of rise in pumping power loss also incurred. 6.84% enhancement in pumping power loss observed for optimum flow rate and particle volume concentration which has not as much pronounced effect as enhancement in thermal efficiency and exergetic efficiency.

  10. Experimental validation of dynamic simulation of the flat plate collector in a closed thermosyphon solar water heater

    DEFF Research Database (Denmark)

    Taherian, H.; Kolaei, Alireza Rezania; Sadeghi, S.

    2011-01-01

    This work studies the dynamic simulation of thermosyphon solar water heater collector considering the weather conditions of a city in north of Iran. The simulation was done for clear and partly cloudy days. The useful energy, the efficiency diagrams, the inlet and the outlet of collector, center...

  11. Experimental validation of dynamic simulation of the flat plate collector in a closed thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Taherian, H.; Rezania, A.; Sadeghi, S.; Ganji, D.D.

    2011-01-01

    This work studies the dynamic simulation of thermosyphon solar water heater collector considering the weather conditions of a city in north of Iran. The simulation was done for clear and partly cloudy days. The useful energy, the efficiency diagrams, the inlet and the outlet of collector, center of the absorber and center of the glass cover temperatures, were obtained. The simulation results were then compared with the experimental results in fall and showed a good agreement.

  12. Annual measured and simulated thermal performance analysis of a hybrid solar district heating plant with flat plate collectors and parabolic trough collectors in series

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    Flat plate collectors have relatively low efficiency at the typical supply temperatures of district heating networks (70–95 °C). Parabolic trough collectors retain their high efficiency at these temperatures. To maximize the advantages of flat plate collectors and parabolic trough collectors in l...... for this type of hybrid solar district heating plants with flat plate collectors and parabolic trough collectors in the Nordic region, but also introduce a novel design concept of solar district heating plants to other high solar radiation areas....... in large solar heating plants for a district heating network, a hybrid solar collector field with 5960 m2 flat plate collectors and 4039 m2 parabolic trough collectors in series was constructed in Taars, Denmark. The design principle is that the flat plate collectors preheat the return water from...

  13. Development of a correlation for parameter controlling using exergy efficiency optimization of an Al_2O_3/water nanofluid based flat-plate solar collector

    International Nuclear Information System (INIS)

    Shojaeizadeh, Ehsan; Veysi, Farzad

    2016-01-01

    Highlights: • Exergy efficiency optimization of a flat-plate collector with Al_2O_3 nanofluid is studied. • Solar radiation and ambient temperature are assumed to be uncontrollable. • Solar collector inlet temperature is influenced by the presence of reservoir tank. • A suitable exponential correlation is proposed for the optimized exergy efficiency. • This exponential correlation also is used for controlling independent parameters. - Abstract: The current study deals with the exergy efficiency optimization of an Al_2O_3/water nanofluid-based flat-plate solar collector according to a mathematical optimization (Sequential Quadratic Programming (SQP) method). This study takes into account exergy efficiency optimization when solar radiation and ambient temperature parameters are assumed to be uncontrollable and presented to a wide range of transient data of climatic conditions where these might take place during spring and summer seasons of Kermanshah (Iran), and perform two main cases as follows: (1) the fluid temperature at the inlet of solar collector, T_i, is independent of storage tank (open loop); (2) the fluid temperature at the inlet of solar collector, T_i, is influenced by the presence of storage tank (closed loop). In any conditions of each case studies (working fluid with and without nanoparticles), a suitable decreasing exponential correlation as function of T_a/G_t values (i.e. ambient temperature to solar radiation ratio) is developed for the optimized exergy efficiency and also well controlling independent parameters values (mass flow rate of fluid, nanoparticle volume concentration and collector inlet temperature). Also, it is concluded that each of optimized parameters and the optimum exergy efficiency is of a linear relation with each other.

  14. Experimental and numerical study of heat transfer phenomena, inside a flat-plate integrated collector storage solar water heater (ICSSWH), with indirect heat withdrawal

    International Nuclear Information System (INIS)

    Gertzos, K.P.; Pnevmatikakis, S.E.; Caouris, Y.G.

    2008-01-01

    The thermal behavior of a particular flat-plate integrated collector storage solar water heater (ICSSWH) is examined, experimentally and numerically. The particularity consists of the indirect heating of the service hot water, through a heat exchanger incorporated into front and back major surfaces of the ICSSWH. Natural and forced convection mechanisms are both examined. A prototype tank was fabricated and experimental data of temperature profiles are extracted, during various energy withdrawals. A 3D computational fluid dynamics (CFD) model was developed and validated against experimental results. Numerical predictions are found highly accurate, providing thus the use of the 3D CFD model for the optimization of this and similar devices

  15. COMPARATIVE FIELD EXPERIMENTAL INVESTIGATIONS OF DIFFERENT FLAT PLATE SOLAR COLLECTORS

    Directory of Open Access Journals (Sweden)

    Guangming Chen

    2015-12-01

    Full Text Available Full-scale traditional metal solar collectors and solar collector specimens fabricated from polymeric materials were investigated in the present study. A polymeric collector is 67.8% lighter than a traditional metal solar collector, and a metal solar collector with transparent plastic covering is 40.3% lighter than a traditional metal solar collector. Honeycomb multichannel plates made from polycarbonate were chosen to create a polymeric solar collector. A test rig for the natural circulation of the working fluid in a solar collector was built for a comparative experimental investigation of various solar collectors operating at ambient conditions. It was shown experimentally that the efficiency of a polymeric collector is 8–15% lower than the efficiency of a traditional collector.

  16. Development of an economic solar heating system with cost efficient flat plate collectors

    Science.gov (United States)

    Eder-Milchgeisser, W.; Burkart, R.

    1980-10-01

    Mass produced flat plate solar collectors were worked into the design of a system for heating a swimming pool and/or providing domestic hot water. The collector characteristics, including physical and mechanical data as well as theoretical energy conversion efficiency, are presented. The collector was tested and service life efficiency was determined. The mounting of the collector, depending on roof type, is explained. Both in service and laboratory test results demonstrate the cost effectiveness of the system. Further improvement of efficiency is envisaged with automatic flow control in the solar collector and hot water circuits.

  17. Recent advances in flat plate photovoltaic/thermal (PV/T) solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Adnan; Othman, Mohd Yusof; Ruslan, Mohd Hafidz; Mat, Sohif; Sopian, Kamaruzzaman [Solar Energy Research Institute Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2011-01-15

    Flat plate photovoltaic/thermal (PV/T) solar collector produces both thermal energy and electricity simultaneously. This paper presents the state-of-the-art on flat plate PV/T collector classification, design and performance evaluation of water, air and combination of water and/or air based. This review also covers the future development of flat plate PV/T solar collector on building integrated photovoltaic (BIPV) and building integrated photovoltaic/thermal (BIPVT) applications. Different designs feature and performance of flat plate PV/T solar collectors have been compared and discussed. Future research and development (R and D) works have been elaborated. The tube and sheet design is the simplest and easiest to be manufactured, even though, the efficiency is 2% lower compared to other types of collectors such as, channel, free flow and two-absorber. It is clear from the review that for both air and water based PV/T solar collectors, the important key factors that influenced the efficiency of the system are the area where the collector covered, the number of passes and the gap between the absorber collector and solar cells. From the literature review, it is obvious that the flat plate PV/T solar collector is an alternative promising system for low-energy applications in residential, industrial and commercial buildings. Other possible areas for the future works of BIPVT are also mentioned. (author)

  18. Efficiencies of flat plate solar collectors at different flow rates

    DEFF Research Database (Denmark)

    Chen, Ziqian; Furbo, Simon; Perers, Bengt

    2012-01-01

    Two flat plate solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one collector is equipped with an ETFE foil between...... the absorber and the cover glass and the other is without ETFE foil. The efficiencies for the collectors are tested at different flow rates. On the basis of the measured efficiencies, the efficiencies for the collectors as functions of flow rate are obtained. The calculated efficiencies are in good agreement...

  19. Optimal design and placement of serpentine heat exchangers for indirect heat withdrawal, inside flat plate integrated collector storage solar water heaters (ICSSWH)

    Energy Technology Data Exchange (ETDEWEB)

    Gertzos, K.P.; Caouris, Y.G.; Panidis, T. [Dept. of Mechanical Engineering and Aeronautics, University of Patras, 265 00 Patras (Greece)

    2010-08-15

    Parameters that affect the temperature at which service hot water (SHW) is offered by an immersed tube heat exchanger (HX), inside a flat plate Integrated Collector Storage Solar Water Heater (ICSSWH), are examined numerically, by means of Computational Fluid Dynamics (CFD) analysis. The storage water is not refreshed and serves for heat accumulation. Service hot water is drawn off indirectly, through an immersed serpentine heat exchanger. For the intensification of the heat transfer process, the storage water is agitated by recirculation through a pump, which goes on only when service water flows inside the heat exchanger. Three main factors, which influence the performance, are optimized: The position of the HX relative to tank walls, the HX length and the tube diameter. All three factors are explored so that to maximize the service water outlet temperature. The settling time of the optimum configuration is also computed. Various 3-D CFD models were developed using the FLUENT package. The heat transfer rate between the two circuits of the optimum configuration is maintained at high levels, leading to service water outlet temperatures by 1-7 C lower than tank water temperatures, for the examined SHW flow rates. The settling time is retained at sufficient law values, such as 20 s. The optimal position was found to lay the HX in contact with the front and back walls of the tank, with an optimum inner tube diameter of 16 mm, while an acceptable HX length was found to be about 21.5 m. (author)

  20. An Experimental and Analytical Study of a Radiative Cooling System with Unglazed Flat Plate Collectors

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Taherian, Hessam

    2012-01-01

    plate solar collectors in a humid area, Babol, Iran, is assessed both experimentally and numerically. Different methods available in the literature are reviewed and by using a widely accepted model, the sky temperature is determined. The mathematical model for a flat plate solar collector is used...... as a guideline to derive the governing equations of a night sky radiator. Then, a cooling loop, including a storage tank, pump, connecting pipes, and a radiator has been studied experimentally. The water is circulated through the unglazed flat-plate radiator having 4 m2 of collector area at night to be cooled...

  1. Analysis and validation of a quasi-dynamic model for a solar collector field with flat plate collectors and parabolic trough collectors in series for district heating

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2018-01-01

    performance of the hybrid solar district heating plants is also presented. The measured and simulated results show that the integration of parabolic trough collectors in solar district heating plants can guarantee that the system produces hot water with relatively constant outlet temperature. The daily energy......A quasi-dynamic TRNSYS simulation model for a solar collector field with flat plate collectors and parabolic trough collectors in series was described and validated. A simplified method was implemented in TRNSYS in order to carry out long-term energy production analyses of the whole solar heating...... plant. The advantages of the model include faster computation with fewer resources, flexibility of different collector types in solar heating plant configuration and satisfactory accuracy in both dynamic and long-term analyses. In situ measurements were taken from a pilot solar heating plant with 5960 m...

  2. Experimental analysis of solar thermal integrated MD system for cogeneration of drinking water and hot water for single family villa in dubai using flat plate and evacuated tube solar collectors

    DEFF Research Database (Denmark)

    Asim, Muhammad; Imran, Muhammad; Leung, Michael K.H.

    2017-01-01

    This paper presents the experimental analysis performed on solar thermal integrated membrane distillation (MD) system using flat plate and evacuated tube collectors. The system will be utilized for cogeneration of drinking water and domestic hot water for single family in Dubai comprising of four...... to five members. Experiments have been performed in Ras Al Khaimah Research and Innovation Centre (RAKRIC) facility. The experimental setup has been installed to achieve the required production of 15–25 L/d of drinking water and 250 L/d of hot water for domestic purposes. Experiments have been performed...

  3. Flat-plate solar collector - installation package

    Science.gov (United States)

    1978-01-01

    Package includes installation, operation and maintenance manual for collector, analysis of safety hazards, special handling instructions, materials list, installation drawings, and warranty and certification statement. Manual includes instructions for roof preparation and for preparing collector for installation. Several pages are devoted to major and minor repairs.

  4. An investigation on the performance characteristics of solar flat plate collector with different selective surface coatings

    Energy Technology Data Exchange (ETDEWEB)

    Madhukeshwara, N. [Department of Mechanical Engineering, B.I.E.T, Davanagere, Karnataka (India); Prakash, E.S. [Department of Studies in Mechanical Engineering, U.B.D.T.C.E, Davanagere, Karnataka (India)

    2012-07-01

    In the present work, investigations are made to study performance characteristics of solar flat plate collector with different selective surface coatings. Flat plate collector is one of the important solar energy trapping device which uses air or water as working fluid. Of the many solar collector concepts presently being developed, the relative simple flat plate solar collector has found the widest application so far. Its characteristics are known, and compared with other collector types, it is the easiest and least expensive to fabricate, install, and maintain. Moreover, it is capable of using both the diffuse and the direct beam solar radiation. For residential and commercial use, flat plate collectors can produce heat at sufficiently high temperatures to heat swimming pools, domestic hot water, and buildings; they also can operate a cooling unit, particularly if the incident sunlight is increased by the use of reflector. Temperatures up to 70 C are easily attained by flat plate collectors. With very careful engineering using special surfaces, reflectors to increase the incident radiation and heat resistant materials, higher operating temperatures are feasible.

  5. Experimental evaluation of flat plate solar collector using nanofluids

    International Nuclear Information System (INIS)

    Verma, Sujit Kumar; Tiwari, Arun Kumar; Chauhan, Durg Singh

    2017-01-01

    Highlights: • Solar collectors are special kind of heat exchangers. • Particle concentration is important parameter for thermal conductivity of nanofluid. • Rise of Bejan number indicates systems qualitative response. • Multi walled carbon nanotube is best performing. - Abstract: The present analysis focuses on a wide variety of nanofluids for evaluating performance of flat plate solar collector in terms of various parameters as well as in respect of energy and exergy efficiency. Also, based on our experimental findings on varying mass flow rate, the present investigation has been conducted with optimum particle volume concentration. Experiments indicate that for ∼0.75% particle volume concentration at a mass flow rate of 0.025 kg/s, exergy efficiency for Multi walled carbon nanotube/water nanofluid is enhanced by 29.32% followed by 21.46%, 16.67%, 10.86%, 6.97% and 5.74%, respectively for Graphene/water, Copper Oxide water, Aluminum Oxide/water, Titanium oxide/water, and Silicon Oxide/water respectively instead of water as the base fluid. Entropy generation, which is a drawback, is also minimum in Multiwalled carbon nanotube/water nanofluids. Under the same thermophysical parameters, the maximum drop in entropy generation can be observed in Multiwalled carbon nanotube/water, which is 65.55%, followed by 57.89%, 48.32%, 36.84%, 24.49% and 10.04%, respectively for graphene/water, copper oxide/water, Aluminum/water, Titanium Oxide /water, and Silicon oxide /water instead of water as the base fluid. Rise of Bejan number towards unity emphasizes improved system performance in terms of efficient conversion of the available energy into useful functions. The highest rise in energy efficiency of a collector has been recorded in Multiwalled carbon nanotube/water, which is 23.47%, followed by 16.97%, 12.64%, 8.28%, 5.09% and 4.08%, respectively for graphene/water, Copper oxide/water, Aluminum oxide/water, Titanium oxide /water, and Silicon oxide/water instead of

  6. High Performance Flat Plate Solar Thermal Collector Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rockenbaugh, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lovullo, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lisell, Lars [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barker, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hanckock, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This report was prepared for the General Services Administration by the National Renewable Energy Laboratory. The Honeycomb Solar Thermal Collector (HSTC) is a flat plate solar thermal collector that shows promising high efficiencies over a wide range of climate zones. The technical objectives of this study are to: 1) verify collector performance, 2) compare that performance to other market-available collectors, 3) verify overheat protection, and 4) analyze the economic performance of the HSTC both at the demonstration sites and across a matrix of climate zones and utility markets.

  7. Development of a selective thin film and of a hermetically sealed flat plate solar collector with gas filling

    Science.gov (United States)

    Zernial, W.

    1982-12-01

    The industrial productibility of a selective absorbing thin film was investigated on the basis of reactive cathodic sputtering of Ni. On substrates of 1.8 sq m of Al, Cu, steel and stainless steel, solar absorption values up to 97% were achieved at emissivities of 5 to 10%. A prototype flat plate collector for high temperatures with two covers and hermetical sealing was developed. The technical data of the collector were measured, dependent on the selectivity of the absorber, gas fillings of dry air, argon or SF6 and the geometry and were compared with those of an evacuated flat plate collector. A hermetical sealed double flat plate collector for low temperatures was developed which has the advantage of lower no load temperatures and higher energy gain for heating swimming pool water compared with a conventional flat plate collector. The insolation values on collectors were measured and were used for a calculation of the energy gains of different collector types.

  8. Energy Analysis of Solar Collector With perforated Absorber Plate

    Directory of Open Access Journals (Sweden)

    Ammar A. Farhan

    2017-09-01

    Full Text Available The thermal performance of three solar collectors with 3, 6 mm and without perforation absorber plate was assessed experimentally. The experimental tests were implemented in Baghdad during the January and February 2017. Five values of airflow rates range between 0.01 – 0.1 m3/s were used through the test with a constant airflow rate during the test day. The variation of the following parameters air temperature difference, useful energy, absorber plate temperature, and collector efficiency was recorded every 15 minutes. The experimental data reports that the increases the number of absorber plate perforations with a small diameter is more efficient rather than increasing the hole diameter of the absorber plate with decreasing the perforation numbers. Maximum air temperature difference throughout the solar collector with 3, 6 mm perforations and without perforations are 17, 15, and 12 oC, respectively. Also, it can be concluded that the energy gained from the solar collector with 3 mm perforation absorber plate is 28.2 % more than the energy gained from solar collector without holes per day for 0.1 m3/s airflow rate. The maximum values of the thermal performance curves are 0.67, 0.64, and 0.56 for the solar collector with 3, 6 mm, and without perforations, respectively.

  9. Comparison of Thermal Performances between Low Porosity Perforate Plate and Flat Plate Solar Air Collector

    Science.gov (United States)

    Chan, Hoy-Yen; Vinson, A. A.; Baljit, S. S. S.; Ruslan, M. H.

    2018-04-01

    Flat plate solar air collector is the most common collector design, which is relatively simpler to fabricate and lower cost. In the present study, perforated plate solar collector was developed to improve the system thermal performance. A glazed perforated plate of 6mm holes diameter with square geometry was designed and installed as the absorber of the collector. The influences of solar radiation intensity and mass flow rate on the thermal performance were investigated. The perforated collector was compared with the flat plate solar collector under the same operating conditions. The highest values of thermal efficiency in this study for the perforated plate (PP) and the flat plate (FP) solar collectors were 59% and 36% respectively, at solar radiation intensity of 846 Wm-2 and mass flow rate of 0.02 kgs-1. Furthermore, PP collector gave better thermal performance compared to FP collector; and compared to previous studies, the present perforated design was compatible with the flat plate with double pass designs.

  10. Finite element analysis of a solar collector plate using two plate geometries

    Directory of Open Access Journals (Sweden)

    Diego Manuel Medina Carril

    2016-09-01

    Full Text Available The thermal behavior of an absorber plate in a solar collector is investigated using finite element analysis. The thermal behavior and efficiency of two absorber plate geometries are studied, using a typical solar collector with a rectangular profile as reference, and a proposed absorber plate with curved geometry. An analysis of the most important parameters involved in the design of the absorber plate was carried out, indicating that the curved geometry of the absorber plate yields an average efficiency ~25% higher than the conventional rectangular geometry. The results suggest that a curved profile made of materials such as aluminum with thermal conductivity higher than 200W/m°C, plate thickness of the order of 2-3mm and with a large density of tubes per unit area of the collector´s plate greatly benefits the thermal efficiency of the solar collector.

  11. Efficiency improvement of flat plate solar collector using reflector

    Directory of Open Access Journals (Sweden)

    Himangshu Bhowmik

    2017-11-01

    Full Text Available Solar collectors are the main components of a solar heating system. The collectors collect the sun’s energy, transform this radiation into heat, and then transfer this heat into a fluid, water or air, which has many household or industrial applications. This paper introduces a new technology to improve the performance of the solar thermal collectors. The solar reflector used here with the solar collector to increase the reflectivity of the collector. Thus, the reflector concentrates both direct and diffuse radiation of the sun toward the collector. To maximize the intensity of incident radiation, the reflector was allowed to change its angle with daytime. The radiations coming from the sun’s energy were converted into heat, and then this heat was transferred to the collector fluid, water. A prototype of a solar water heating system was constructed and obtained the improvement of the collector efficiency around 10% by using the reflector. Thus, the present solar water heating systems having the best thermal performance compared to the available systems.

  12. Experimental Evaluation of a Flat Plate Solar Collector Under Hail City Climate

    Directory of Open Access Journals (Sweden)

    N. Ben Khedher

    2018-04-01

    Full Text Available Flat plate solar water heaters are widely used for water heating in low-temperature residential applications. In this paper the thermal performance of a solar flat plate water heater under Hail weather conditions (latitude 27°52΄N longitude ‎41°69΄E was experimentally investigated. Fluid was circulated through the imbedded copper tubes in the flat plate collector and inlet and outlet temperatures of the fluid were noted at five minute intervals. The experimental-time was between 9:00AM-15:00PM. A study was carried out experimentally to present the efficiency curves of a flat plate solar collector at different flow rates. ASHRAE standard 93-2003 was followed for calculation of instantaneous efficiency of solar collector. Result shows that the flow rate of the circulating fluid highly influence the thermal efficiency of the solar collector. Optimum flow rate of 2.5L/min leads to maximum collector efficiency.

  13. Low cost bare-plate solar air collector

    Science.gov (United States)

    Maag, W. L.; Wenzler, C. J.; Rom, F. E.; Vanarsdale, D. R.

    1980-09-01

    A low cost, bare plate solar collector for preheating ambient air was developed. This type of solar heating system would be applicable for preheating ventilation air for public buildings or other commercial and industrial ventilation requirements. Two prototype collectors were designed, fabricated and installed into an instrumented test system. Tests were conducted for a period of five months. Results of the tests showed consistent operating efficiencies of 60 percent or greater with air preheat temperature uses up to 20 degrees for one of the prototypes. The economic analyses indicated that this type of solar system was economically viable. For the materials of construction and the type of fabrication and installation perceived, costs for the bare plate solar collector are attainable. Applications for preheating ventilation air for schools were evaluated and judged to be economically viable.

  14. Standardized performance tests of collectors of solar thermal energy - A flat-plate copper collector with parallel mylar striping

    Science.gov (United States)

    Johnson, S. M.

    1976-01-01

    Basic test results are reported for a flat plate solar collector whose performance was determined in a solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and one coolant flow rate. Collector efficiency is correlated in terms of inlet temperature and flux level.

  15. Application of solar flat plate collector in automobile industry

    Energy Technology Data Exchange (ETDEWEB)

    Wawge, P. [Peenya Alloys Pvt. Ltd., Parvati, Pune (India)

    2004-07-01

    In any industry, heating, cooling and compressed air the costliest part, which affects the production cost of any product. There are three types of indirect heat requirement or the requirement of heat can be divided in the three main categories. (1) low temp. 40 - 60 Deg. (2) Medium temp. 80 - 150 deg. (3) High Temp applications - above 150. Solar Flat Collectors have been proven for the use of solar energy for medium temp. application in hotels, boiler feed water preheating, dairy for pasteurization and some other indirect heating applications. There is another neglected area of application of Solar Flat Plate collector is heat treatment for powder coating plants where heat requirement is bet 50 Deg C - 70 Deg C. In any automobile industry the aesthetic or look of the vehicle place a very important role as far as the sale is concern (after the mechanical performance). The aesthetic means the body and colour of the vehicle. To get a long lasting good quality color, the powder coating procedure plays a major role. Before powder coating there is requirement of different chemical treatment for the removal of rust, grease and other cleaning of the specific sheet metal body parts. The time duration and chemical composition is depends on the selection of body material. A proven method of a chemical treatment is seven / eight tank process. The common system of heating chemicals is by way of electrical heaters, by diesel or other fuel fired boilers. This increases the cost of heat treatment process due the high cost of electricity (for industries rate of electricity is 1.5 to 2 times than the domestic rate) or oils. This can be replaced by Solar water heating system which can efficiently generate the temp of liquid upto 85 Deg C. (orig.)

  16. Performance of wickless heat pipe flat plate solar collectors having different pipes cross sections geometries and filling ratios

    International Nuclear Information System (INIS)

    Hussein, H.M.S.; El-Ghetany, H.H.; Nada, S.A.

    2006-01-01

    In the present study, the effect of wickless heat pipe cross section geometry and its working fluid filling ratio on the performance of flat plate solar collectors has been investigated experimentally. Three groups of wickless heat pipes having three different cross section geometries (namely, circular, elliptical and semi-circular cross sections) were designed and manufactured. Each group of three wickless heat pipes was charged with three different distilled water filling ratios of 10%, 20% and 35%. Each wickless heat pipe was then incorporated into a prototype flat plate solar collector developed for the purpose of the present study. The prototypes wickless heat pipe flat plate solar collectors have been investigated experimentally at different inlet cooling water temperatures, two different cooling water mass flow rates and under the meteorological conditions of Cairo, Egypt. The experimental results indicate that the elliptical cross section wickless heat pipe flat plate solar collectors have better performance than the circular cross section ones at low water filling ratios. The optimum water filling ratio of the elliptical cross section wickless heat pipe solar collector is about 10%, while it is very close to 20% for the circular cross section one. Also, the water filling ratio corresponding to the flooding limit of the elliptical wickless heat pipe solar collector is lower than that of the circular one. At 20% water filling ratio, the semi-circular cross section wickless heat pipe solar collector has bad performance compared with that of the other cross sections

  17. Experimental and numerical investigation of a linear Fresnel solar collector with flat plate receiver

    International Nuclear Information System (INIS)

    Bellos, Evangelos; Mathioulakis, Emmanouil; Tzivanidis, Christos; Belessiotis, Vassilis; Antonopoulos, Kimon A.

    2016-01-01

    Highlights: • A linear Fresnel solar collector with flat plate receiver is investigated. • The collector is investigated experimentally in energetic and exergetic terms. • The developed numerical model is validated with the experimental results. • The operation with thermal oil is also examined with the developed model. • The final results prove satisfying performance for medium temperature levels. - Abstract: In this study a linear Fresnel solar collector with flat plate receiver is investigated experimentally and numerically with Solidworks Flow Simulation. The developed model combines optical, thermal and flow analysis; something innovative and demanding which leads to accurate results. The main objective of this study is to determine the thermal, the optical and the exergetic performance of this collector in various operating conditions. For these reasons, the developed model is validated with the respective experimental data and after this step, the solar collector model is examined parametrically for various fluid temperature levels and solar incident angles. The use of thermal oil is also analyzed with the simulation tool in order to examine the collector performance in medium temperature levels. The experiments are performed with water as working fluid and for low temperature levels up to 100 °C. The final results proved that this solar collector is able to produce about 8.5 kW useful heat in summer, 5.3 kW in spring and 2.9 kW in winter. Moreover, the operation of this collector with thermal oil can lead to satisfying results up to 250 °C.

  18. Influence of nanofluids on the efficiency of Flat-Plate Solar Collectors (FPSC)

    Science.gov (United States)

    Nejad, Marjan B.; Mohammed, H. A.; Sadeghi, O.; Zubeer, Swar A.

    2017-11-01

    A numerical investigation is performed using finite volume method to study the laminar heat transfer in a three-dimensional flat-plate solar collector using different nanofluids as working fluids. Three nanofluids with different types of nanoparticles (Ag, MWCNT and Al2O3 dispersed in water) with 1-2 wt% volume fractions are analyzed. A constant heat flux, equivalent to solar radiation absorbed by the collector, is applied at the top surface of the absorber plate. In this study, several parameters including boundary conditions (different volume flow rates, different fluid inlet temperatures and different solar irradiance at Skudai, Malaysia), different types of nanoparticles, and different solar collector tilt angles are investigated to identify their effects on the heat transfer performance of FPSC. The numerical results reveal that the three types of nanofluid enhance the thermal performance of solar collector compared to pure water and FPSC with Ag nanofluid has the best thermal performance enhancement. For all the cases, the collector efficiency increased with the increase of volume flow rate while fluid outlet temperature decreased. It is found that FPSC with tilt angle of 10° and fluid inlet temperature of 301.15 K has the best thermal performance.

  19. Optimization of the functional domain of flat plate collectors

    Science.gov (United States)

    Ritoux, G.; Irigaray, J.-L.

    1981-12-01

    The variations of the extracted heat flux as function of the temperature of the heat transfer fluid in black and selective surface solar collectors are examined. The heat flux is calculated based on the difference of the initial to the stage of thermal equilibrium of the fluid. A nonlinear system of equations is developed and solved by a fast, iterative method to obtain the equilibrium temperatures. It is found that more flux can be extracted from the solar heat by a collector with only one glass cover than with more than one cover. The captured flux is proportional to the coefficient of transmission of the glass coverings, to the coefficient of absorption of the collector, and to the incident flux. Black painted surfaces were more absorbent than selective surfaces, and highest collection efficiencies were displayed by low temperature collectors. Charts of effective uses of the respective types of collectors for heating swimming pools, hot water, home heat, and for refrigeration and air-conditioning are provided.

  20. Water heating solar system using collector with polycarbonate absorber surface

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Luiz Guilherme Meira de; Sodre, Dilton; Cavalcanti, Eduardo Jose Cidade; Souza, Luiz Guilherme Vieira Meira de; Mendes, Jose Ubiragi de Lima [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)], e-mails: lguilherme@dem.ufrn.br, diltonsodre@ifba.edu.br, ubiragi@ct.ufrn.br

    2010-07-01

    It is presented s solar collector to be used in a heating water for bath system, whose main characteristics are low cost and easy fabrication and assembly processes. The collector absorber surface consists of a polycarbonate plate with an area of 1.5 m{sup 2}. The water inlet and outlet are made of PVC 50mm, and were coupled to a 6mm thick polycarbonate plate using fiberglass resin. A 200 liters thermal reservoir will be used. This reservoir is also alternative. The absorber heating system works under thermo-siphon regimen. Thermal parameters will be evaluated to prove the feasibility of the studied solar heating system to obtain bath water for a four people family. (author)

  1. Investigation of thermal behaviour, pressure drop, and pumping power in a Cu nanofluid-filled solar flat-plate collector

    Directory of Open Access Journals (Sweden)

    Shamshirgaran S. Reza

    2017-01-01

    Full Text Available The evaluations of the performance of solar flat-plate collectors are reported in the literature. A computer program developed by MATLAB has been applied for modelling the performance of a solar collector under steady state laminar conditions. Results demonstrate that Cu-water nanofluid would be capable of boosting the thermal efficiency of the collector by 2.4% at 4% volume concentration in the case of using Cunanofluid instead of just water as the working fluid. It is noteworthy that, dispersing the nanoparticles into the water results in a higher pressure drop and, therefore, a higher power consumption for pumping the nanofluid within the collector. It has been estimated for the collector understudy, that the increase in the pressure drop and pumping power to be around 30%.

  2. Theoretical and experimental investigation of wickless heat pipes flat plate solar collector with cross flow heat exchanger

    International Nuclear Information System (INIS)

    Hussein, H.M.S.

    2007-01-01

    In this work, a wickless heat pipes flat plate solar collector with a cross flow heat exchanger was investigated theoretically and experimentally under the meteorological conditions of Cairo, Egypt. The author's earlier simulation program of wickless heat pipes flat plate solar water heaters was modified to be valid for the present type of wickless heat pipes solar collector by including the solution of the dimensionless governing equations of the present analysis. For verifying the modified simulation program, a wickless heat pipes flat plate solar collector with a cross flow heat exchanger was designed, constructed, and tested at different meteorological conditions and operating parameters. These parameters include different cooling water mass flow rates and different inlet cooling water temperatures. The comparison between the experimental results and their corresponding simulated ones showed considerable agreement. Under different climatic conditions, the experimental and theoretical results showed that the optimal mass flow rate is very close to the ASHRAE standard mass flow rate for testing conventional flat plate solar collectors. Also, the experimental and theoretical results indicated that the number of wickless heat pipes has a significant effect on the collector efficiency

  3. Standarized performance tests of collectors of solar thermal energy: A steel flat-plate collector with two transparent covers and a proprietary coating

    Science.gov (United States)

    1976-01-01

    Basic test results of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator are given. The collector was tested over ranges of inlet temperature and flux level.

  4. Preheating of tap water with solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Granum, H; Raaen, H

    1992-05-05

    In 1991 SINTEF Architecture and Building Technology won the second prize in 'The Nordic Competition for Low Energy Buildings' with a project proposal named 'LOWe'. The paper gives a description of the energy-saving features of this project, particularly the use of a solar collector for preheating of tap water. Compared with the economic profitability of other saving efforts in the project, such as good thermal insulation and efficient heat recovering system, the system for solar preheating of tap water does not seem very attractive for the time being. Loose estimates indicate a cost of close of NOK 1.00 per kWh for the produced energy in the solar collector, while the present price for electricity in Norway is about NOK 0.50 per kWh. Compared with a heat pump solution however the energy cost is not unreasonable.

  5. Effect of openings collectors and solar irradiance on the thermal efficiency of flat plate-finned collector for indirect-type passive solar dryer

    Science.gov (United States)

    Batubara, Fatimah; Dina, Sari Farah; Klaudia Kathryn Y., M.; Turmuzi, M.; Siregar, Fitri; Panjaitan, Nora

    2017-06-01

    Research on the effect of openings solar collector and solar irradiance to thermal efficiency has been done. Solar collector by flat plate-finned type consists of 3 ply insulator namely wood, Styrofoam and Rockwool with thickness respectively are 10 mm, 25 mm and 50 mm. Absorber plate made of aluminum sheet with thickness of 0.30 mm, painted by black-doff. Installation of 19 units fins (length x height x thickness: 1000x20x10 mm) on the collector will increase surface area of absorber so it can receive much more solar energy. The solar collector cover is made of glass (thickness of 5 mm). During the research, the solar irradiance and temperature of collector are measured and recorded every five minutes. Temperature measurement performed on the surface of the absorber plate, inside of collector, surface cover and the outer side insulator (plywood). This data is used to calculate the heat loss due to conduction, convection and radiation on the collector. Openings of collectors vary as follows: 100%, 75%, 15% and 0% (total enclosed). The data collecting was conducted from 09.00 am to 17.00 pm and triplicates. The collector thermal efficiency calculated based on the ratio of the amount of heat received to the solar irradiance absorbed. The results show that each of openings solar collector has different solar irradiance (because it was done on a different day) which is in units of W/m2: 390 (100% open), 376 (75% open), 429 (15% open), and 359 (totally enclosed). The highest thermal efficiency is in openings variation of 15% opened. These results indicate that the efficiency of the collector is influenced by the solar irradiance received by the collector and the temperature on the collector plate. The highest thermal efficiency is in variation of openings 15%. These indicate that the efficiency of the collector was influenced by solar irradiance received by the collector and openings of the collector plate.

  6. Standardized performance tests of collectors of solar thermal energy-a flat-plate collector with a single-tube serpentine flow distribution

    Science.gov (United States)

    Johnson, S.

    1976-01-01

    This preliminary data report gives basic test results of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and coolant flow rates. Collector efficienty is correlated in terms of inlet temperature and flux level.

  7. A study of the flat plate solar collector in Guinea

    International Nuclear Information System (INIS)

    Boye Barry, M.

    1990-12-01

    In this paper, we study a collector, made by cheap local materials (wood, aluminium, etc.), and prepared in the carpenteries, and in the mechanic work rooms with a simple technology. The efficiency of our collector is compared with several variants made in other countries. (author). 9 refs, 6 figs, 2 tabs

  8. Daily efficiency of flat-plate solar air collectors for grain drying

    Energy Technology Data Exchange (ETDEWEB)

    Ting, K.C.; Shove, G.C.

    1983-01-01

    Single cover flat-plate solar collectors incorporated into walls and roofs of farm buildings have been used to heat ambient air for low temperature grain drying systems. Large surface area and high airflow rate are common features of these collectors. The drying period may range from several days to several weeks. Therefore, a knowledge of the variations of the collectors' daily efficiencies with respect to their design parameters would be helpful in applying solar collectors to grain drying. The objective of this study was to develop a simpler means of direct calculation of a collector's daily efficiency based on its design parameters. Many factors, such as configuration of the collector, airflow rate, weather conditions, etc. will affect the performance of solar collectors. A large number of varied conditions need to be tested in order to investigate the effect of different parameters on the collector performance. To facilitate this investigation, a computer simulation model developed by Ting was used to calculate the daily efficiencies of collectors under different operating conditions. The computer model was verified by Morrison's experimental data. Based on the simulation results, a functional relationship was developed between the daily efficiencies of collectors and their design parameters.

  9. Modelling and analysis of a heating system for industrial application, using flat-plate solar-collectors with single and double cover glasses

    International Nuclear Information System (INIS)

    Maraslis, A.A.

    1987-01-01

    A calculational methodology for dimensioning a flat-plate solar-collector arrangement, which fulfils the energy requirement of a heat transfer system in one of the steps of the uranium recovery process, from the uranium-phosphorus ore at Itataia, Ceara, in Brazil. The PROSOL-1 and PROSOL-2 computer codes for determining the total area required by collector arrangement-with single and double cover glasses, respectively- taking into account the system design and meteorological conditions of the regions, were used. These codes optimize the series/parallel arranges of collectors in the whole complex and, determine the water flow in each system and the average efficiency of the collector arrangement. The technical and economical feasibility for both collector arrangement with single and double cover glasses, were verified. It was concluded that, the last one is more advantageous, allowing a reduction of 30% in the total collector area. (M.C.K.) [pt

  10. Effect of Glass Thickness on Performance of Flat Plate Solar Collectors for Fruits Drying

    Directory of Open Access Journals (Sweden)

    Ramadhani Bakari

    2014-01-01

    Full Text Available This study aimed at investigating the effect of thickness of glazing material on the performance of flat plate solar collectors. Performance of solar collector is affected by glaze transmittance, absorptance, and reflectance which results into major heat losses in the system. Four solar collector models with different glass thicknesses were designed, constructed, and experimentally tested for their performances. Collectors were both oriented to northsouth direction and tilted to an angle of 10° with the ground toward north direction. The area of each collector model was 0.72 m2 with a depth of 0.15 m. Low iron (extra clear glass of thicknesses 3 mm, 4 mm, 5 mm, and 6 mm was used as glazing materials. As a control, all collector performances were analysed and compared using a glass of 5 mm thickness and then with glass of different thickness. The results showed that change in glass thickness results into variation in collector efficiency. Collector with 4 mm glass thick gave the best efficiency of 35.4% compared to 27.8% for 6 mm glass thick. However, the use of glass of 4 mm thick needs precautions in handling and during placement to the collector to avoid extra costs due to breakage.

  11. Small-Scale Flat Plate Collectors for Solar Thermal Scavenging in Low Conductivity Environments

    Directory of Open Access Journals (Sweden)

    Emmanuel Ogbonnaya

    2017-01-01

    Full Text Available There is great opportunity to develop power supplies for autonomous application on the small scale. For example, remote environmental sensors may be powered through the harvesting of ambient thermal energy and heating of a thermoelectric generator. This work investigates a small-scale (centimeters solar thermal collector designed for this application. The absorber is coated with a unique selective coating and then studied in a low pressure environment to increase performance. A numerical model that is used to predict the performance of the collector plate is developed. This is validated based on benchtop testing of a fabricated collector plate in a low-pressure enclosure. Model results indicate that simulated solar input of about 800 W/m2 results in a collector plate temperature of 298 K in ambient conditions and up to 388 K in vacuum. The model also predicts the various losses in W/m2 K from the plate to the surroundings. Plate temperature is validated through the experimental work showing that the model is useful to the future design of these small-scale solar thermal energy collectors.

  12. Energy and Exergy Analysis of Dual Channel Solar Air Collector with Different Absorber Plates Geometry

    Directory of Open Access Journals (Sweden)

    Najim A. Jassim

    2018-04-01

    Full Text Available Flat-plate collector considers most common types of collectors, for ease of manufacturing and low price compared with other collectors. The main aim of the present work is to increase the efficiency of the collector, which can be achieved by improving the heat transfer and minimize heat loss experimentally. Five types of solar air collectors have been tested, which conventional channel with a smooth absorber plate (model I, dual channel with a smooth absorber plate (model II, dual channel with perforating “V” corrugated absorber plate (model III, dual channel with internal attached wire mesh (model Ⅳ, and dual channel with absorber sheet of transparent honeycomb, (model Ⅴ. The dual channel collector used for increasing heat transfer area and heat removal factor to improve thermal performance. The outdoor test was conducted during the period December (2016 to February (2017 at different mass flow rates 0.0217 kg/s, 0.0271 kg/s and 0.0325 kg/s. The experiments were carried out from 8:30 AM to 3:00 PM for clear days. Experimental results show that the average thermal efficiency was (72.2 % for model (III, (40.2 % for model (I, (51.6 % for model (II, (65.1 % for model (Ⅳ and (59.7 % for model (Ⅴ. At the last part of the study, the exergy analyses were derived for both collectors. The results of this part showed that the conventional channel model (I is having largest irreversibility, and the dual channel collector model (III is having a greatest exergetic efficiency.

  13. Efficiency of liquid flat-plate solar energy collector with solar tracking system

    Directory of Open Access Journals (Sweden)

    Chekerovska Marija

    2015-01-01

    Full Text Available An extensive testing programme is performed on a solar collector experimental set-up, installed on a location in Shtip (Republic of Macedonia, latitude 41º 45’ and longitude 22º 12’, in order to investigate the effect of the sun tracking system implementation on the collector efficiency. The set-up consists of two flat plate solar collectors, one with a fixed surface tilted at 30о towards the South, and the other one equipped with dual-axis rotation system. The study includes development of a 3-D mathematical model of the collectors system and a numerical simulation programme, based on the computational fluid dynamics (CFD approach. The main aim of the mathematical modelling is to provide information on conduction, convection and radiation heat transfer, so as to simulate the heat transfer performances and the energy capture capabilities of the fixed and moving collectors in various operating modes. The feasibility of the proposed method was confirmed by experimental verification, showing significant increase of the daily energy capture by the moving collector, compared to the immobile collector unit. The comparative analysis demonstrates a good agreement between the experimental and numerically predicted results at different running conditions, which is a proof that the presented CFD modelling approach can be used for further investigations of different solar collectors configurations and flow schemes.

  14. Increasing efficiency of a 33 MW OTEC in Indonesia using flat-plate solar collector for the seawater heater

    Directory of Open Access Journals (Sweden)

    Iwan Rohman Setiawan

    2017-07-01

    Full Text Available This paper presents a design concept of Ocean Thermal Energy Conversion (OTEC plant built in Mamuju, West Sulawesi, with 33 MWe and 7.1% of the power capacity and efficiency, respectively. The generated electrical power and the efficiency of OTEC plant are enhanced by a simulation of a number of derived formulas. Enhancement of efficiency is performed by increasing the temperature of the warm seawater toward the evaporator from 26˚C up to 33.5˚C using a flat-plate solar collector. The simulation results show that by increasing these a water temperature up to 33.5˚C, the generated power will increase up to 144.155 MWe with the OTEC efficiency up to 9.54%, respectively. The required area of flat-plate solar collector to achieve the results is around 6.023 x 106 m2.

  15. Variation of reflected radiation from all reflectors of a flat plate solar collector during a year

    International Nuclear Information System (INIS)

    Pavlović, Zoran T.; Kostić, Ljiljana T.

    2015-01-01

    In this paper the impact of flat plate reflectors (bottom, top, left and right reflectors) made of Al, on total solar radiation on a solar collector during a day time over a whole year is analyzed. An analytical model for determining optimum tilt angles of a collector and reflectors for any point on the Earth is proposed. Variations of reflectors' optimal inclination angles with changes of the collector's optimal tilt angle during the year are also calculated. Optimal inclination angles of the reflectors for the South directed solar collector are calculated and compared to experimental data. It is shown that optimal inclination of the bottom reflector is the lowest in December and the highest in June, while for the top reflector the lowest value is in June and the highest value is in December. On the other hand, optimal inclination of the left and right side reflectors for optimum tilt angle of the collector does not change during the year and it is 66°. It is found that intensity of the solar radiation on the collector increases for about 80% in the summer period (June–September) by using optimally inclined reflectors, in comparison to the collector without reflectors. - Highlights: • The impacts of flat plate reflectors on solar radiation on the collector are given. • The results of the optimal inclinations of reflectors during the year are shown. • The solar radiation on the collector with reflectors is 80% higher in the summer. • This model may be applied on thermal, PV, PV/T and energy harvesting systems

  16. Tårs 10000 m2 CSP + Flat Plate Solar Collector Plant - Cost-Performance Optimization of the Design

    DEFF Research Database (Denmark)

    Perers, Bengt; Furbo, Simon; Tian, Zhiyong

    2016-01-01

    , was established. The optimization showed that there was a synergy in combining CSP and FP collectors. Even though the present cost per m² of the CSP collectors is high, the total energy cost is minimized by installing a combination of collectors in such solar heating plant. It was also found that the CSP......A novel solar heating plant with Concentrating Solar Power (CSP) collectors and Flat Plate (FP) collectors has been put into operation in Tårs since July 2015. To investigate economic performance of the plant, a TRNSYS-Genopt model, including a solar collector field and thermal storage tank...

  17. Evaluation of a tracking flat-plate solar collector in Brazil

    International Nuclear Information System (INIS)

    Maia, Cristiana B.; Ferreira, André G.; Hanriot, Sérgio M.

    2014-01-01

    The continuing research for an alternative power source due to the perceived scarcity of fuel fossils has, in recent years, given solar energy a remarkable edge. Nevertheless, the Earth's daily and seasonal movement affects the intensity of the incident solar radiation. Devices can track the sun in order to ensure optimum positions with regard to incident solar radiation, maximizing the absorbed solar energy, and the useful energy gain. In this paper, a mathematical model is developed to estimate the solar radiation absorbed, the useful energy gain, and the efficiency of a flat-plate solar collector in Brazil. The results for a sun tracking flat-plate solar collector were compared to fixed devices. The full tracking system with rotation about two axes presented higher absorbed energy, when compared to the rotation about a single axe and to a fixed collector. Also, it was shown that the tilt angle for a fixed solar collector does not cause significant variations in the useful energy gain or in the absorbed solar radiation, for the same azimuth angle. - Highlights: • A model was developed for solar radiation based on experimental data for K T . • Useful energy gain and efficiency of a flat-plate solar collector were evaluated for a one-year period. • Several sun tracking systems were compared to fixed devices. • Tilt angle for a fixed device does not significantly affect the useful energy gain

  18. Effect of Installation of Solar Collector on Performance of Balcony Split Type Solar Water Heaters

    Directory of Open Access Journals (Sweden)

    Xu Ji

    2015-01-01

    Full Text Available The influences of surface orientation and slope of solar collectors on solar radiation collection of balcony split type solar water heaters for six cities in China were analyzed by employing software TRNSYS. The surface azimuth had greater effect on solar radiation collection in high latitude regions. For deviation of the surface slope angle within ±20° around the optimized angle, the variation of the total annual collecting solar radiation was less than 5%. However, with deviation of 70° to 90°, the variation was up to 20%. The effects of water cycle mode, reverse slope placement of solar collector, and water tank installation height on system efficiency were experimentally studied. The thermal efficiencies of solar water heater with single row horizontal arrangement all-glass evacuated tubular collector were higher than those with vertical arrangement at the fixed surface slope angle of 90°. Compared with solar water heaters with flat-plate collector under natural circulation, the system thermal efficiency was raised up to 63% under forced circulation. For collector at reverse slope placement, the temperature-based water stratification in water tank deteriorated, and thus the thermal efficiency became low. For improving the system efficiency, an appropriate installation height of the water tank was suggested.

  19. The capture of submicron particles by collector plates - Wind-tunnel investigations

    International Nuclear Information System (INIS)

    Gauthier, Daniel

    1971-01-01

    The deposition of submicron particles on collector plates parallel to the flow was studied experimentally in a wind-tunnel. The validity of a theoretical model based on brownian diffusion was investigated and its Inadequacies tested. The aerosol sample consisted of uranine particles (mean geometrical radius: about 0. 1 μm). The average flow speeds varied from 1 to 10 m/s and the length of the collector plates between 1 and 10 cm. Results showed that capture was mainly due to diffusion and was in good agreement with the theoretical model; however a noticeable deposit of particles on the front part of the collector edge was observed. Sedimentation was insignificant in almost all the cases. (author) [fr

  20. Comparative performance of twenty-three types of flat plate solar energy collectors

    Science.gov (United States)

    Simon, F. F.

    1975-01-01

    Report compares efficiencies of 23 solar collectors for four different purposes: operating a Rankine-cycle engine, heating or absorption air conditioning, heating hot water, and heating a swimming pool.

  1. Analysis of absorbed energy and efficiency of a solar flat plate collector

    Directory of Open Access Journals (Sweden)

    Anderson Miguel Lenz

    2017-07-01

    Full Text Available The highest percentage in home electricity demands in Brazil lies with the water heating systems, where the electric shower has a great contribution in consumption. The use of solar thermal panels is an alternative to minimize the strain on the electrical system by heating water. Current study evaluates a water heating system built with materials commonly used in home constructions. The tested collector is a 1 m² flat plate. Experiments were conducted at the State University of Western Paraná (UNIOESTE, campus Cascavel, Paraná State, Brazil. Temperature data were collected by PT100 sensors and solar radiation was measured with a pyranometer, coupled to a CR-1000 datalogger, with readings and collection every 5 minutes for 1 year. Data collection and analysis showed that the system presented monthly efficiency ranging between 33.7 and 53.54%, and energy absorbed between 30.79 and 75.29 kWh m-².month. Results show the system is a good option for use in residential or rural water heating due to decrease in the electric bill.

  2. Craft-Joule Project: Stagnation proof transparently insulated flat plate solar collector (static)

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, A; Cadafalch, J; Perez-Segarra, C.D. [Universitat Politecnica de Catalunya, Barcelona (Spain)] (and others)

    2000-07-01

    The STATIC (STAgnation proof Transparently Insulated flat plate Solar Collector) project is a Craft-Joule Project within the framework of the Non Nuclear Energy Programme Joule III coordinated by the Centre Technologic de Transferencia de Calor (CTTC). The core group of SMEs involved in the project has its main economical activity in the field of solar thermal systems at low temperature level (domestic hot water, solar heating, etc.). Beyond this, a large application potential exists for solar heating at medium temperature level (from 80 to 160 Celsius degrees) : industrial process heat, solar cooling and air conditioning, solar drying , distillation and desalination. Three of the four SME proposers are located in Southern Europe and in the Caribean, where a continuos increase of the demand for air conditioning and cooling has been demonstrated in the last years. The recent development of flat plate solar collectors with honeycomb-type transparent insulation cover has shown that this type of collectors can become a low cost alternative to evacuated tube and high concentrating CPC collectors in the medium temperature range from 80 to 160 Celsius degrees. With the expected reduction of collector cost, that forms 30%-50% of total system cost, a decisive break-through of solar thermal systems using heat in the medium temperature range can be achieved. The feasibility and good performance of these solar collectors has been proved in several prototypes. Nevertheless, up to now no commercial products are available. In order to reach this, the following developments of new concepts are necessary and are being carried out within this project: solution of the problem of overheating: development of collector versions for different working temperatures: optimization of the design with the support of high level numerical simulation. Several prototypes of the new solar collectors are being tested. System tests will also be carried or for two test arrays of optimized collector

  3. Analysis of a solar collector field water flow network

    Science.gov (United States)

    Rohde, J. E.; Knoll, R. H.

    1976-01-01

    A number of methods are presented for minimizing the water flow variation in the solar collector field for the Solar Building Test Facility at the Langley Research Center. The solar collector field investigated consisted of collector panels connected in parallel between inlet and exit collector manifolds to form 12 rows. The rows were in turn connected in parallel between the main inlet and exit field manifolds to complete the field. The various solutions considered included various size manifolds, manifold area change, different locations for the inlets and exits to the manifolds, and orifices or flow control valves. Calculations showed that flow variations of less than 5 percent were obtainable both inside a row between solar collector panels and between various rows.

  4. Investigation of one-dimensional heat flow in a solarflat plate collector with sun tracing system

    Directory of Open Access Journals (Sweden)

    H Samimi Akhijahani

    2016-09-01

    Full Text Available Introduction Drying is one of the most common methods for storing food and agricultural products. During drying process, free water that causes the growth of microorganisms and spoilage of products is removed from the product. There are several methods for drying of agricultural products. one of the most important methods of investment is drying by using sunlight. Iran is situated at 25- 43oE longitude and mean solar radiation is about 4.9 kwh.m-2.d-1. Because of the proper solar radiations in 95% of the agricultural areas in Iran, solar drying is widely used for drying of fruits and vegetables. The use of solar dryer causes saving in energy consumption and processing costs for drying of products in farms and gardens. Several researchers investigated heat transfer and heat flow in dryers. Selection of appropriate method was carried out for drying of agricultural products using heat pump. Experiments were done and mathematical relationships were estimated to obtain correlation parameters between Reynolds number and Nusselt number for the three cases of solar dryer (cabinet, indirect and combination.The best working conditions were determined for three types of solar collectors (flat, finned and corrugated. In this study, the process of heat transfer and heat transfer coefficient of a solar dryer with and without rotation of absorber plate was compared. Materials and Methods The experiments were conducted in Azarshahr, East Azarbayjan province, Iran in September 2014. Newton's law of thermodynamic was used to analyze the working condition of solar absorber. For this purpose the absorber plate was divided into four equal parts. According to the thermal equations and related boundary conditions as well as the relationship between heat transfer coefficient and the temperature gradient, equation 1 for the Nusselet number obtained: 1 Beside the relationship between Nusselt number and heat transfer coefficient is defined as equation 2: 2 Finally

  5. Drying of fruits and vegetables using a flat plate solar collector with convective air flow

    International Nuclear Information System (INIS)

    Mansoor, K.K.; Hanif, M.

    2011-01-01

    This paper presents the analysis of drying of different fruits and vegetables dried by a flat plate solar collector developed at the Department of Agricultural Mechanization, Khyber PukhtunKhwa Agricultural University Peshawar, Pakistan. A small flat plate solar collector is designed and tested for its maximum performance in terms of efficiency with different convective flow rates. The collector assembly is divided into two parts. The flat plate solar collector and the drying chamber. The materials used for flat plate solar collector are wood, steel sheet, Insulation materials, and glass sheet as covering material. The insulation box (0.9 x 1.8 x 0.3 meter) is made up of wood of popular and deodar, to be fully isolated with the help of polystyrene. The absorber is black painted v-corrugated steel sheet. Collector has a tilt angle of 34 deg. (Equivalent to the latitude of Peshawar). The covering material is (0.9 x 1.8 meter) and 5 mm thick glass sheet placed at the top of the wooden box. The collector is supported and tilted with the help of a frame made up of iron angled arms. While the drying chamber is a (1 X 0.5 x 0.3 meter) wooden box connected to the outlet duct of the collector with the help of polyvinylchloride pipe. Experiments were conducted different fruits and vegetables and different parameters like moisture lost by the products in each hour, drying rate at each hour of drying, humidity and temperature of the drying chamber. It was observed that the products such as bitter guard and onion were dried in 10 to 2 hours up to moisture content less then 8%. These two product lost 8% to 10% moisture during each hour of drying. While grapes and Green chili are dried in 24 to 25 hours up to moisture content less then 8%. These two products lost 4% to 5% moisture in each hour of drying. The drying rate of all the products dried was very much consistent. It was observed that onion and bitter guard showed a good drying rate of 0.03[g(H/sub 2/O)/g(d.m).cm/ 2 hr] to

  6. Cost estimates for flat plate and concentrator collector arrays

    Science.gov (United States)

    Shimada, K.

    1982-01-01

    The current module and installation costs for the U.S. National Photovoltaic Program's grid-connected systems are significantly higher than required for economic viability of this alternative. Attention is accordingly given to the prospects for installed module cost reductions in flat plate, linear focus Fresnel concentrator, and point focus Fresnel concentrator candidate systems. Cost projections indicate that all three systems would meet near-term and midterm goals, provided that module costs of $2.80/W(p) and $0.70/W(p), respectively, are met. The point focus Fresnel system emerges as the most viable for the near term.

  7. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    OpenAIRE

    Marroquín de Jesús, Á.; Olivares-Ramírez, J.M.; Ramos-López, G.A.; Pless, R.C.

    2009-01-01

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198-L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m², about 20% smaller than ...

  8. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    OpenAIRE

    Á. Marroquín de Jesús; J.M. Olivares–Ramírez; G.A. Ramos–López; R.C. Pless

    2009-01-01

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198–L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m2, about 20% smaller than ...

  9. Entransy analysis on the thermal performance of flat plate solar air collectors

    Institute of Scientific and Technical Information of China (English)

    Jie Deng; Xudong Yang; Yupeng Xu; Ming Yang

    2017-01-01

    Based on the thermo-electric analogy (the so-called thermal entransy analysis), the unified airside convective heat transfer coefficient for different sorts of flat plate solar air collectors (FPSACs) is identified in terms of colector aperture area. In addition, the colector thermodynamic characteristic matching coefficient is defined to depict the matching property of collector thermal performance between the collector airside heat transfer and the total heat losses. It is found that the airside convective heat transfer coefficient can be experimentally determined by collector thermal performance test method to compare the airside thermal performances of FPSACs with different types of airflow structures. Moreover, the smaler the colector thermodynamic characteristic matching coefficient is, the better the thermodynamic perfect degree of a FPSAC is. The minimum limit value of the collector thermodynamic matching coefficient is close to zero but it can not vanish in practical engineering. Parameter sensitivity analysis on the total entransy dissipation and the entransy increment of a general FPSAC is also undertaken. The results indicate that the effective way of decreasing total entransy dissipation and enhancing the useful entransy increment is improving the efficiency intercept of the FPSAC. This is equivalent to the cognition result of thermal analysis. However, the evaluation indices identified by the thermal entransy analysis can not be extracted by singular thermal analysis.

  10. Solar water disinfecting system using compound parabolic concentrating collector

    Energy Technology Data Exchange (ETDEWEB)

    El-Ghetany, H.H.; Saitoh, T.S. [Tohoku Univ., Sendai (Japan)

    2000-05-31

    Solar water disinfection is an alternative technology using solar radiation and thermal treatment to inactivate and destroy pathogenic microorganisms present in water. The Compound Parabolic Concentrating, (CPC) collector can be used as an efficient key component for solar disinfectanting system. Two types of the CPC collectors are studied, namely the transparent-tube and the Copper-tube CPC collector. It is found that after 30 minutes of exposing the water sample to solar radiation or heating it up to 65 degree C for a few minuets all the coliform bacterial present in the contaminated water sample were completely eliminated. In this article, the effect of water temperature on the disinfecting process was presented. Thermal and micro-biological measurements were also made to evaluate the system performance. (author)

  11. Selectively coated high efficiency glazing for solar-thermal flat-plate collectors

    International Nuclear Information System (INIS)

    Ehrmann, N.; Reineke-Koch, R.

    2012-01-01

    In order to increase the efficiency of solar-thermal flat-plate collectors at temperatures above 100 °C or with low solar irradiation, we implement a double glazing with a low-emitting (low-e) coating on the inner pane to improve the insulation of the transparent cover. Since commercially available low-e glazing provides only insufficient solar transmittance for the application in thermal flat-plate collectors we are developing a sputter-deposited low e-coating system based on transparent conductive oxides which provides a high solar transmittance of 85% due to additional antireflective coatings and the use of low-iron glass substrates. Durability tests of the developed coating system show that our low e-coating system is well suitable even at high temperatures, humidity and condensation.

  12. Integrated collector storage solar water heater: Temperature stratification

    International Nuclear Information System (INIS)

    Garnier, C.; Currie, J.; Muneer, T.

    2009-01-01

    An analysis of the temperature stratification inside an Integrated Collector Storage Solar Water Heater (ICS-SWH) was carried out. The system takes the form of a rectangular-shaped box incorporating the solar collector and storage tank into a single unit and was optimised for simulation in Scottish weather conditions. A 3-month experimental study on the ICS-SWH was undertaken in order to provide empirical data for comparison with the computed results. Using a previously developed macro model; a number of improvements were made. The initial macro model was able to generate corresponding water bulk temperature in the collector with a given hourly incident solar radiation, ambient temperature and inlet water temperature and therefore able to predict ICS-SWH performance. The new model was able to compute the bulk water temperature variation in different SWH collectors for a given aspect ratio and the water temperature along the height of the collector (temperature stratification). Computed longitudinal temperature stratification results obtained were found to be in close agreement with the experimental data.

  13. Optimum solar flat-plate collector slope: Case study for Helwan, Egypt

    International Nuclear Information System (INIS)

    Elminir, Hamdy K.; Ghitas, Ahmed E.; El-Hussainy, F.; Hamid, R.; Beheary, M.M.; Abdel-Moneim, Khaled M.

    2006-01-01

    This article examines the theoretical aspects of choosing a tilt angle for the solar flat-plate collectors used in Egypt and make recommendations on how the collected energy can be increased by varying the tilt angle. The first objective in this investigation is to perform a statistical comparison of three specific anisotropic models (Tamps-Coulson, Perez and Bugler) to recommend one that is general and is most accurate for estimating the solar radiation arriving on an inclined surface. Then, the anisotropic model that provides the most accurate estimation of the total solar radiation has been used to determine the optimum collector slope based on the maximum solar energy availability. This result has been compared with the results provided by other models that use declination, daily clearness index and ground reflectivity. The study revealed that Perez's model shows the best overall calculated performance, followed by the Tamps-Coulson then Bugler models

  14. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    Directory of Open Access Journals (Sweden)

    Á. Marroquín de Jesús

    2009-07-01

    Full Text Available Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198–L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m2, about 20% smaller than comparable copper–tube–based collectors offered in the market. Temperature measurements conducted over a 30–day period gave values which were a few degrees lower than the theoretically calculated water temperatures. Momentary thermal efficiency values between 35% and 77% were observed. The water temperature achieved in the tank at the end of the day aver ages 65°C in winter weather conditions in the central Mexican highland. This design of solar water heater is well suited to Mexican conditions, as it makes use of the high local intensity of the solar radiation, and as the channel shape of the ducts minimizes bursting during the rare occurrences of freezing temperatures in the region; it also has the advantage of being manufacturable at low cost from simple materials.

  15. Standardized performance tests of collectors of solar thermal energy: A selectively coated, flat-plate copper collector with one transparent cover and a tube-to-tube spacing of 5 5/8 inches

    Science.gov (United States)

    1976-01-01

    This preliminary data report gives basic test results of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and coolant flow rates. Collector efficiency is correlated in terms of inlet temperature and flux level.

  16. Standard performance tests of collectors of solar thermal energy: A selectively coated, flat-plate copper collector with one transparent cover and a tube-to-tube spacing of 3-7/8 inches

    Science.gov (United States)

    1976-01-01

    Basic test results are given of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes, and coolant flow rates. Collector efficiency is correlated in terms of inlet temperature and flux level.

  17. Experimental analysis of distinct design of a batch solar water heater with integrated collector storage system

    Directory of Open Access Journals (Sweden)

    Varghese Jaji

    2007-01-01

    Full Text Available The performance of a new design of batch solar water heater has been studied. In this system, the collector and storage were installed in one unit. Unlike the conventional design consisting of small diameter water tubes, it has a single large diameter drum which serves the dual purpose of absorber tube and storage tank. In principle it is a compound parabolic collector. The drum is sized to have a storage capacity of 100 liter to serve a family of four persons. The tests were carried out with a single glass cover and two glass covers. The tests were repeated for several days. Performance analysis of the collector has revealed that it has maximum mean daily efficiency with two glass covers as high as 37.2%. The maximum water temperature in the storage tank of 60°C has been achieved for a clear day operation at an average solar beam radiation level of 680 W/m2 and ambient temperature of 32°C. To judge the operating characteristics and to synchronize utility pattern of the collector, the different parameters such as efficiency, mean plate temperature and mass flow rate has been investigated.

  18. Performance analysis of photovoltaic thermal (PVT) water collectors

    International Nuclear Information System (INIS)

    Fudholi, Ahmad; Sopian, Kamaruzzaman; Yazdi, Mohammad H.; Ruslan, Mohd Hafidz; Ibrahim, Adnan; Kazem, Hussein A.

    2014-01-01

    Highlights: • Performances analysis of PVT collector based on energy efficiencies. • New absorber designs of PVT collectors were presented. • Comparison present study with other absorber collector designs was presented. • High efficiencies were obtained for spiral flow absorber. - Abstract: The electrical and thermal performances of photovoltaic thermal (PVT) water collectors were determined under 500–800 W/m 2 solar radiation levels. At each solar radiation level, mass flow rates ranging from 0.011 kg/s to 0.041 kg/s were introduced. The PVT collectors were tested with respect to PV efficiency, thermal efficiency, and a combination of both (PVT efficiency). The results show that the spiral flow absorber exhibited the highest performance at a solar radiation level of 800 W/m 2 and mass flow rate of 0.041 kg/s. This absorber produced a PVT efficiency of 68.4%, a PV efficiency of 13.8%, and a thermal efficiency of 54.6%. It also produced a primary-energy saving efficiency ranging from 79% to 91% at a mass flow rate of 0.011–0.041 kg/s

  19. Greenhouse heating with a fresh water floating collector solar pond

    International Nuclear Information System (INIS)

    Arbel, A.; Sokolov, M.

    1991-01-01

    The fresh water floating collector solar pond was investigated both experimentally and theoretically in a previous work, and it is now matched, by simulation, with the heat load requirements of a greenhouse. Results of the simulation indicate that such a pond is a potential energy source for greenhouse heating. This is especially true when the material properties are such that solar absorption and storage are enhanced. This paper reports that to demonstrate this point, three sets of collectors constructed with materials of different physical (radiation) properties were tested. One set is constructed of common materials which are readily available and are normally used as covers for greenhouses. The second set made of improved materials which are also available but have a smaller long-wave transmittance. The last set made of ideal material which additionally possesses selective radiation absorption properties. Collectors made of ideal materials make a superior solar pond; thus, manufacturing films with improved properties should become a worthwhile challenge for the agricultural polyethylene-films industry. Preliminary economic studies indicate that even with the low oil (<$20/Bbl) prices which exist between 1986-1989, the fresh water floating collectors solar pond provides an economically attractive alternative to the conventional oil-burning heating system. This is especially true in mild climate areas and when the large initial investment is justified by long-term greenhouse utilization planning

  20. Investigation of Thermal Performance of Flat Plate and Evacuated Tubular Solar Collectors According to a New Dynamic Test Method

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Wang, Zhifeng; Fan, Jianhua

    2012-01-01

    obtain fluid thermal capacitance in data processing. Then theoretical analysis and experimental verification are carried out to investigate influencing factors of obtaining accurate and stable second order term. A flat plate and ETC solar collector are compared using both the new dynamic method......A new dynamic test method is introduced. This so called improved transfer function method features on two new collector parameters. One is time term which can indicate solar collector's inner heat transfer ability and the other is a second order term of collector mean fluid temperature which can...... and a standard method. The results show that the improved function method can accurately and robustly estimate these two kinds of solar collectors....

  1. Achievement report for fiscal 1981 on Sunshine Program survey and research. Joint projects on solar energy between Japan and Australia, etc. (Joint efforts for high-grade flat-plate collector development); 1981 nendo Nichigonado taiyo energy gijutsu kyoryoku jigyo seika hokokusho. Nichigo taiyo energy gijutsu kyoryoku (kokyu heiban collector kaihatsu kyoryoku)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    Investigated at DET (Division of Energy Technology) are a unit for controlling air convection in between a heat collector heat-collecting plate and the cover, testing methods, and under-floor heat accumulation using a horizontal rock bed. DMC (Division of Mineral Chemistry) is engaged in the study of black Ni selective absorption film formation on a metal plate and a reflection-preventing film for a heat collector. Monash University studies methods for testing heat collectors, transfer of heat, heat pipe, tracking mechanism, etc. Melbourne University is dedicated to computer model calculation involving solar energy utilization. Sydney University deals with collectors, selective absorption films, absorption type refrigerators, heat accumulation, and desalination of water. Under study at New South Wales University are passive solar systems, photothermal collectors, solar cells, etc. The Beaseley Corporation is a manufacturer of heater collectors and water heaters in South Australia, and a visit is paid to the corporation for the study of its manufacturing process. The Rheem Corporation manufactures water heaters in New South Wales, and its presence in the solar collector industry is known. (NEDO)

  2. Lobster eye as a collector for water window microscopy

    Science.gov (United States)

    Pina, L.; Maršíková, V.; Inneman, A.; Nawaz, M. F.; Jančárek, A.; Havlíková, R.

    2017-08-01

    Imaging in EUV, SXR and XR spectral bands of radiation is of increasing interest. Material science, biology and hot plasma are examples of relevant fast developing areas. Applications include spectroscopy, astrophysics, Soft X-ray Ray metrology, Water Window microscopy, radiography and tomography. Especially Water Window imaging has still not fully recognized potential in biology and medicine microscopy applications. Theoretical study and design of Lobster Eye (LE) optics as a collector for water window (WW) microscopy and comparison with a similar size ellipsoidal mirror condensor are presented.

  3. Performance Study of Photovoltaic-Thermal (Pv/T) Solar Collector with ·-Grooved Absorber Plate

    International Nuclear Information System (INIS)

    Mohd Yusof Othman; Hafidz Ruslan; Kamaruzzaman Sopian; Jin, G.L.

    2009-01-01

    A hybrid photovoltaic-thermal solar collector has been designed, built and its performance has been studied. The advantage of the collector is that it can generate electricity and heat simultaneously. Photovoltaic module SHARP NE-80E2EA with maximum output power of 80 W was used to generate electricity. The module also acts as heat absorber of the collector. Single pass ·-groove collector made of aluminium sheet with 0.7 mm thickness has been used to collect heat generated. Study was conducted under a designed halogen lamps solar simulator with intensities set at 386 ± 8 Wm -2 and 817 ± 8 Wm -2 . The speed of air passing through the collector was set between (69.6 ± 2.2) x 10 -4 kg/s to (695.8 ± 2.2) x 10 -4 kg/s. The objective of the study is to compare the performance of PV/T collector with and without ·-groove absorber. The study found that the PV/T collector with ·-groove absorber plate has higher efficiency than the PV/T without ·-groove absorber. The electrical and thermal efficiencies are also increased when radiation intensity and speed of air increase. (author)

  4. Experimental Investigation of a Solar Greenhouse Heating System Equipped with a Parabolic Trough Solar Concentrator and a Double-Purpose Flat Plate Solar Collector

    Directory of Open Access Journals (Sweden)

    M Jafari

    2017-10-01

    Full Text Available Introduction Greenhouses provide a suitable environment in which all the parameters required for growing the plants can be controlled throughout the year. Greenhouse heating is one of the most important issues in productivity of a greenhouse. In many countries, heating costs in the greenhouses are very high, having almost 60-80% of the total production costs. In recent years, several studies have attempted to reduce the heating costs of the greenhouses by applying more energy efficient equipment and using the renewable energy sources as alternatives or supplementary to the fossil fuels. In the present study a novel solar greenhouse heating system equipped with a parabolic trough solar concentrator (PTC and a flat-plate solar collector has been developed. Therefore, the aim of this paper is to investigate the performance of the proposed heating system at different working conditions. Materials and Methods The presented solar greenhouse heating system was comprised of a parabolic trough solar concentrator (PTC, a heat storage tank, a pump and a flat plate solar collector. The PTC was constructed from a polished stainless steel sheet (as the reflector and a vacuum tube receiver. The PTC was connected to the tank by using insulated tubes and a water pump was utilized to circulate the working fluid trough the PTC and the heat exchanger installed between walls of the tank. The uncovered solar collector was located inside the greenhouse. During the sunshine time, a fraction of the total solar radiation received inside the greenhouse is absorbed by the solar collector. This rises the temperature of the working fluid inside the collector which led to density reduction and natural flow of the fluid. In other words, the collector works as a natural flow flat plate solar collector during the sunshine time. At night, when the greenhouse temperature is lower than tank temperature, the fluid flows in a reverse direction through the solar collector and the

  5. Numerical Study on the Effect of Distribution Plates in the Manifolds on the Flow Distribution and Thermal Performance of a Flat Plate Solar Collector

    Directory of Open Access Journals (Sweden)

    Juan Manuel García-Guendulain

    2018-04-01

    Full Text Available Flow maldistribution represents a problem of particular interest in the engineering field for several thermal systems. In flat plate solar collectors, the thermal efficiency strongly depends on the flow distribution through the riser tubes, where a uniform distribution causes a uniform temperature distribution and therefore a higher efficiency. In this work, a Computational Fluid Dynamics (CFD numerical analysis has been carried out using the commercial software FLUENT®, in order to determine the flow distribution, pressure drop and hence the thermal efficiency of a solar collector with distribution flow plates inside the manifolds. The obtained numerical solution for this type of thermal systems has been validated with experimental results available in literature for laminar and turbulent flow. Four distribution plate configurations were analyzed. Results show that using two distribution plates in each of both manifolds improves the flow uniformity up to 40% under the same operating conditions when distribution plates are not used. Besides, it is shown that there exists an increase in the overall pressure drop which is practically negligible for the tilt angles commonly employed in the installation of flat plate solar collectors in Mexico. The use of closed end distribution plates on the dividing and combining manifolds allows the thermal efficiency to become close to the ideal thermal efficiency which is obtained with a uniform flow distribution.

  6. The sizes of Flat Plate and Evacuated Tube Collectors with Heat Pipe area as a function of the share of solar system in the heat demand

    Directory of Open Access Journals (Sweden)

    Olek Małgorzata

    2016-01-01

    Full Text Available The popularity of solar collectors in Poland is still increasing. The correct location of the collectors and a relatively high density of solar radiation allow delivering heat even in spite of relatively low ambient temperature. Moreover, solar systems used for heating domestic heat water (DHW in summer allow nearly complete elimination of conventional energy sources (e.g. gas, coal. That is why more and more house owners in Poland decide to install solar system installations. In Poland the most common types of solar collectors are flat plate collectors (FPC and evacuated tube collectors with heat pipe (ETCHP; both were selected for the analysis. The heat demand related to the preparation of hot water, connected with the size of solar collectors’ area, has been determined. The analysis includes FPC and ETCHP and heat demand of less than 10 000 kWh/year. Simulations were performed with the Matlab software and using data from a typical meteorological year (TMY. In addition, a 126–year period of measurements of insolation for Krakow has been taken into account. The HDKR model (Hay, Davis, Klucher, Reindl was used for the calculation of solar radiation on the absorber surface. The monthly medium temperature of the absorber depends on the amount of solar system heat and on the heat demand. All the previously mentioned data were used to determine solar efficiency. Due to the fact that solar efficiency and solar system heat are connected, the calculations were made with the use of an iterative method. Additionally, the upper limit for monthly useful solar system heat is resulted from the heat demand and thus the authors prepared a model of statistical solar system heat deviations based on the Monte Carlo method. It has been found that an increase in the useful solar system heat in reference to the heat demand is associated with more than proportional increase in the sizes of the analyzed surfaces of solar collector types.

  7. Air bubble-induced detachment of polystyrene particles with different sizes from collector surfaces in a parallel plate flow chamber

    NARCIS (Netherlands)

    Gomez-Suarez, C; van der Mei, HC; Busscher, HJ

    2001-01-01

    Particle size was found to be an important factor in air bubble-induced detachment of colloidal particles from collector surfaces in a parallel plate flow chamber and generally polystyrene particles with a diameter of 806 nm detached less than particles with a diameter of 1400 nm. Particle

  8. Liquid flat plate collector and pump for solar heating and cooling systems: A collection of quarterly reports

    Science.gov (United States)

    1978-01-01

    Progress in the development, fabrication, and delivery of solar subsystems consisting of a solar operated pump, and solar collectors which can be used in solar heating and cooling, or hot water, for single family, multifamily, or commercial applications is reported.

  9. A Comparison of the Thermodynamic Efficiency of Vacuum Tube and Flat Plate Solar Collector Systems

    Directory of Open Access Journals (Sweden)

    Juozas Bielskus

    2013-12-01

    Full Text Available The article presents simulation based exergy analysis used for comparing solar thermal systems applied for preparing domestic hot water. The simulation of flat and vacuum tube solar collector systems was performed in TRNSYS simulation environment. A period of one year under Lithuanian climate conditions was chosen. Simulation was performed on 6 min time step resolution by calculating energy and exergy flows and creating balance calculation. Assessment results at system and element levels have been presented as monthly variation in efficiency. The conducted analysis has revealed that the systems designed to cover equal heat energy demand operates in different exergetic efficiencies.Article in Lithuanian

  10. Optimization of flat-plate solar energy heat pipe collector parameters

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, L L; Garakovich, L P; Khrustalev, D K

    1984-01-01

    Performance characteristics of flat solar energy collectors with heat pipes have been analysed with regard to various parameters. Their advantages are discussed. The use of heat pipes in solar energy collectors is proved to be efficient.

  11. Study of thermal effects and optical properties of an innovative absorber in integrated collector storage solar water heater

    Science.gov (United States)

    Taheri, Yaser; Alimardani, Kazem; Ziapour, Behrooz M.

    2015-10-01

    Solar passive water heaters are potential candidates for enhanced heat transfer. Solar water heaters with an integrated water tank and with the low temperature energy resource are used as the simplest and cheapest recipient devices of the solar energy for heating and supplying hot water in the buildings. The solar thermal performances of one primitive absorber were determined by using both the experimental and the simulation model of it. All materials applied for absorber such as the cover glass, the black colored sands and the V shaped galvanized plate were submerged into the water. The water storage tank was manufactured from galvanized sheet of 0.0015 m in thickness and the effective area of the collector was 0.67 m2. The absorber was installed on a compact solar water heater. The constructed flat-plate collectors were tested outdoors. However the simulation results showed that the absorbers operated near to the gray materials and all experimental results showed that the thermal efficiencies of the collector are over than 70 %.

  12. Animal or plant: which is the better fog water collector?

    Science.gov (United States)

    Nørgaard, Thomas; Ebner, Martin; Dacke, Marie

    2012-01-01

    Occasional fog is a critical water source utilised by plants and animals in the Namib Desert. Fog basking beetles (Onymacris unguicularis, Tenebrionidae) and Namib dune bushman grass (Stipagrostris sabulicola, Poaceae) collect water directly from the fog. While the beetles position themselves optimally for fog water collection on dune ridges, the grass occurs predominantly at the dune base where less fog water is available. Differences in the fog-water collecting abilities in animals and plants have never been addressed. Here we place beetles and grass side-by-side in a fog chamber and measure the amount of water they collect over time. Based on the accumulated amount of water over a two hour period, grass is the better fog collector. However, in contrast to the episodic cascading water run-off from the grass, the beetles obtain water in a steady flow from their elytra. This steady trickle from the beetles' elytra to their mouth could ensure that even short periods of fog basking--while exposed to predators--will yield water. Up to now there is no indication of specialised surface properties on the grass leafs, but the steady run-off from the beetles could point to specific property adaptations of their elytra surface.

  13. Animal or plant: which is the better fog water collector?

    Directory of Open Access Journals (Sweden)

    Thomas Nørgaard

    Full Text Available Occasional fog is a critical water source utilised by plants and animals in the Namib Desert. Fog basking beetles (Onymacris unguicularis, Tenebrionidae and Namib dune bushman grass (Stipagrostris sabulicola, Poaceae collect water directly from the fog. While the beetles position themselves optimally for fog water collection on dune ridges, the grass occurs predominantly at the dune base where less fog water is available. Differences in the fog-water collecting abilities in animals and plants have never been addressed. Here we place beetles and grass side-by-side in a fog chamber and measure the amount of water they collect over time. Based on the accumulated amount of water over a two hour period, grass is the better fog collector. However, in contrast to the episodic cascading water run-off from the grass, the beetles obtain water in a steady flow from their elytra. This steady trickle from the beetles' elytra to their mouth could ensure that even short periods of fog basking--while exposed to predators--will yield water. Up to now there is no indication of specialised surface properties on the grass leafs, but the steady run-off from the beetles could point to specific property adaptations of their elytra surface.

  14. Performance enhancement studies in a thermosyphon flat plate solar water heater with CuO nanofluid

    Directory of Open Access Journals (Sweden)

    Dasaien Anin Vincely

    2017-01-01

    Full Text Available Experiments were conducted on a thermosyphon type flat plate collector, inclined at 45°, for water heating application. Water and water based nanofluids were used as absorber fluid to gain heat from solar rays incident on the flat plate col-lector. Nanofluids were prepared by adding CuO nanoparticles of 40-50 nm size to the base fluid at 0.1, 0.2, 0.3, and 0.5 wt% (ζ. The hot absorber fluid was made to circulate in the shell side of a heat exchanger, placed at the top of the flat plate collector, where utility water was circulated inside a helically coiled Cu tube. Temperatures at strategic locations in the flat plate collector, working fluid, utility water inlet and outlet were measured. The nanofluid increases the collector efficiency with increasing ζ. A highest efficiency enhancement of 5.7% was observed for the nanofluid with ζ = 0.2 having a mass flow rate of 0.0033 kg/s. The 3-D, steady-state, conjugate heat transfer CFD analyses were carried out using the ANSYS FLUENT 15.0 software. Theoretically estimated buoyancy induced fluid flow rates were close with the CFD predictions and thus validates the computational methodology.

  15. Design, construction and evaluation of solar flat-plate collector simulator based on the thermohydraulic coefficient

    Directory of Open Access Journals (Sweden)

    H Rahmati Aidinlou

    2017-05-01

    Full Text Available Introduction Increasing the area of absorber plate between the flowed air through the duct can be accomplished by corrugating the absorber plate or by using the artificial roughness underside of the absorber plate as the commercial methods for enhancing the thermohydraulic performance of the flat plate solar air heaters. Evaluation of this requires the construction of separated solar air heater which is costly and time consuming. The constructed solar flat-plate collector simulator can be a sufficient solution for obtaining the heat transfer and thermodynamic parameters for evaluating the absorber plate. The inclined broken roughness was chosen as the optimum roughness which is surrounded by three aluminum smooth walls. Materials and Methods The duct for both smooth and roughened plate have been constructed based on the ASHRAE 93-2010 standard. In order to achieve a fully thermal and hydraulic developed flow, the plenum is constructed. The centrifugal fan is considered by applying the required air volume at the pressure drop obtained by the duct, plenum and the orifice meter. The TSI velocity-meter 8355 is used to measure the velocity of air crossing through the pipe connected to the centrifugal fan. The micro manometer Kimo CPE310-s with the resolution of 0.1 Pa is used to measure the pressure drop across the test section of the smooth and roughened duct. The LM35 sensors are used to measure the absorber plate and air temperature through the test section. Obtained parameters are used to calculate the Nusselt number and friction factor across the test section for smooth and roughened absorber plate. The Nusselt number and friction factor parameters which is obtained for smooth absorber plate based on experimental set-up, is compared with Dittus-Bolter and Blasius equations, respectively, for validating the simulator. By calculating the Nusselt number and friction factor, Stanton number is obtained based on the equation (6, and thermohydraulic

  16. Thermal analysis of a solar collector consisting of V cavities for water heating; Analise termica de um coletor solar composto de cavidades V para aquecimento de agua

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Michel Fabio de Souza

    2009-03-15

    The solar water heating is carried through, in Brazil, by means of solar heaters compound for collectors flat plate of the type plate-and-pipes, devices that operate in stationary position and they do not require tracking of the sun. A compound collector for some formed V-trough concentrators can be an alternative to the conventional solar collectors flat plate. This compound collector for V-trough is considered, each one, for side-walls which are specularly reflecting surfaces associates in V (equivalent to a triangular gutter). Next to the vertex to each V-trough concentrators an absorber tube is fixed, for flow of the fluid to be heated. Interconnection of the absorbers tubes forms a similar tubular network existing in solar collectors of the type the plate and pipe. V-trough concentrators with the absorbers tubes are made use in series in the interior a prismatic box, which have one of its faces consisting by a glass covering and directed toward incidence of the solar radiation. An analysis of thermal performance of these devices operating stationary and without tracking of the sun is researched. A mathematical model for the computational simulation of the optical and thermal performance of these concentrative devices is elaborated, whose implementation was carried through software EES (Engineering Equation Solver). The efficiency optics of V-trough concentrators with cylindrical absorbers is calculated from the adaptation of the methodology used for Fraidenraich (1994), proposal for Hollands (1971) for V-trough cavities with plain absorbers. The thermal analysis of the considered collector was based on the applied methodology the CPC for Hsieh (1981) and Leao (1989). Relative results to the thermal performance of V-trough concentrators suggest that these configurations are not competitive, technique and economically, with the conventional plain collectors. Although some geometric configurations presented next thermal efficiencies to the conventional plain

  17. Quantitative measurement of 222Rn in water by the activated charcoal passive collector method: 1. The effect of water in a collector

    International Nuclear Information System (INIS)

    Yoneda, Minoru; Inoue, Yoriteru; Yoshimoto, Keizo

    1994-01-01

    The activated charcoal passive collector method can be applied to measure the concentration of 222 Rn in river water. The 222 Rn collector is composed of dry activated charcoal sealed in a polyethylene bag. However, we found it very difficult to keep activated charcoal in a collector dry during the period the collector was left in a river. The degree of dampness and the time lapsed when activated charcoal became wet were thought to affect the quantity of 222 Rn collected. First, we studied the effect of some parameters in the activated charcoal passive collector method qualitatively in three experiments. We found that the quantity of 222 Rn collected in a collector was not so sensitive to the quantity of activated charcoal in the collector or the thickness of polyethylene film under the condition of wet activated charcoal, and that wet activated charcoal accumulated less 222 Rn than dry activated charcoal. We present some equations which could explain how much 222 Rn was collected in a collector when activated charcoal was submerged directly in water and when activated charcoal was packed in a polyethylene bag but completely wet. These equations were proved effective by being compared with the results of the other experiments. Finally, we recommended some conditions which proved useful when measuring at an actual river

  18. Energy, economic and environmental analysis of metal oxides nanofluid for flat-plate solar collector

    International Nuclear Information System (INIS)

    Faizal, M.; Saidur, R.; Mekhilef, S.; Alim, M.A.

    2013-01-01

    Highlights: • By using nanofluid, smaller and compact solar collector can be produced. • The average value of 220 MJ embodied energy can be saved. • The payback period of using nanofluid solar collector is around 2.4 years. • Around 170 kg less CO 2 emissions in average for nanofluid solar collector. • Environmental damage cost is lower with the nanofluid based solar collector. - Abstract: For a solar thermal system, increasing the heat transfer area can increase the output temperature of the system. However, this approach leads to a bigger and bulkier collector. It will then increase the cost and energy needed to manufacture the solar collector. This study is carried out to estimate the potential to design a smaller solar collector that can produce the same desired output temperature. This is possible by using nanofluid as working fluid. By using numerical methods and data from literatures, efficiency, size reduction, cost and embodied energy savings are calculated for various nanofluids. From the study, it was estimated that 10,239 kg, 8625 kg, 8857 kg and 8618 kg total weight for 1000 units of solar collectors can be saved for CuO, SiO 2 , TiO 2 and Al 2 O 3 nanofluid respectively. The average value of 220 MJ embodied energy can be saved for each collector, 2.4 years payback period can be achieved and around 170 kg less CO 2 emissions in average can be offset for the nanofluid based solar collector compared to a conventional solar collector. Finally, the environmental damage cost can also be reduced with the nanofluid based solar collector

  19. Economical judge possibility uses solar collectors to warm service water and heating

    Directory of Open Access Journals (Sweden)

    Lívia Bodonská

    2006-09-01

    Full Text Available The sun-heated water has been used from before fossil fuels started to determine the direction of our power consumption. This article is focused on the assessing of the use of solar energy as one of inexhaustible resources that has multiple uses, including hot water service systems. Heating is rendered through solar collectors that permit to transform solar energy to warm water. We divide solar collectors into various groups but in principle they are medium temperature collectors and low temperature collectors. The work is directed also on the solar collector market. In our case the market is just at its initial stage as this technology is little known and costs of collectors are rather high, compared to our conditions, on average, they may grow up to 100,000 Slovac crowns per a family house. Because it is the only investment and the costs of operation are minimum throughout the entire collectors lifetime, from the economic point of view, it is a rather advantageous investment. Solar collectors are used in heating and also in hot service water systems in family houses, where they permit to lower costs for the consumption of many kinds of energies. In the hot service water system, solar collectors permit to lower the consumption by almost 70 %. This way of using the solar energy is very prospective and in future it will be used in various sectors

  20. Buoyancy effects on thermal behavior of a flat-plate solar collector

    DEFF Research Database (Denmark)

    Fan, Jianhua; Furbo, Simon

    2008-01-01

    Theoretical and experimental investigations of the flow and temperature distribution in a 12.53 m(2) solar collector panel with an absorber consisting of two vertical manifolds interconnected by 16 parallel horizontal fins have been carried out. The investigations are focused on overheating...... and the influence of the buoyancy effects are considered in the investigations. Further experimental investigations of the solar collector panel are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the back of the absorber tubes. The measured temperatures....... The CFD calculations elucidate the flow and temperature distribution in the collector panels of different designs. Based on the investigations, recommendations are given in order to avoid overheating or boiling problems in the solar collector panel....

  1. Development and evaluation of a multiple-plate fraction collector for sample processing: application to radioprofiling in drug metabolism studies.

    Science.gov (United States)

    Barros, Anthony; Ly, Van T; Chando, Theodore J; Ruan, Qian; Donenfeld, Scott L; Holub, David P; Christopher, Lisa J

    2011-04-05

    Microplate scintillation counters are utilized routinely in drug metabolism laboratories for the off-line radioanalysis of fractions collected during HPLC radioprofiling. In this process, the current fraction collection technology is limited by the number of plates that can be used per injection as well as the potential for sample loss due to dripping or spraying as the fraction collector head moves from well to well or between plates. More importantly, sample throughput is limited in the conventional process, since the collection plates must be manually exchanged after each injection. The Collect PAL, an innovative multiple-plate fraction collector, was developed to address these deficiencies and improve overall sample throughput. It employs a zero-loss design and has sub-ambient temperature control. Operation of the system is completely controlled with software and up to 24 (96- or 384-well) fraction collection plates can be loaded in a completely automated run. The system may also be configured for collection into various-sized tubes or vials. At flow rates of 0.5 or 1.0 mL/min and at collection times of 10 or 15s, the system precisely delivered 83-μL fractions (within 4.1% CV) and 250-μL fractions (within 1.4% CV), respectively, of three different mobile phases into 12 mm × 32 mm vials. Similarly, at a flow rate of 1 mL/min and 10s collection times, the system precisely dispensed mobile phase containing a [(14)C]-radiolabeled compound across an entire 96-well plate (% CV was within 5.3%). Triplicate analyses of metabolism test samples containing [(14)C]buspirone and its metabolites, derived from three different matrices (plasma, urine and bile), indicated that the Collect PAL produced radioprofiles that were reproducible and comparable to the current technology; the % CV for 9 selected peaks in the radioprofiles generated with the Collect PAL were within 9.3%. Radioprofiles generated by collecting into 96- and 384-well plates were qualitatively comparable

  2. A figure of merit for selective absorbers in flat plate solar water heaters

    CSIR Research Space (South Africa)

    Roberts, DE

    2013-12-01

    Full Text Available We derive from first principles an analytical expression for a figure of merit (FM) for a selective solar absorber in a single glazed flat plate water heater. We first show that the efficiency of a collector with an absorber with absorptance α...

  3. Longevity characteristics of flat solar water-heating collectors in hot-water-supply systems. Part 1. Procedure for calculating collector thermal output

    International Nuclear Information System (INIS)

    Avezova, N.R.; Ruziev, O. S.; Suleimanov, Sh. I.; Avezov, R. R.; Vakhidov, A.

    2013-01-01

    A procedure for calculating longevity indices (daily and monthly variations and, hence, annual thermal output) of flat solar water-heating collectors, amount of conditional fuel saved per year by using solar energy, and cost of solar fuel and thermal energy generated in hot-water-supply systems is described. (authors)

  4. Detachment of polystyrene particles from collector surfaces by surface tension forces induced by air-bubble passage through a parallel plate flow chamber

    NARCIS (Netherlands)

    Wit, PJ; vanderMei, HC; Busscher, HJ

    1997-01-01

    By allowing an air-bubble to pass through a parallel plate flow chamber with negatively charged, colloidal polystyrene particles adhering to the bottom collector plate of the chamber, the detachment of adhering particles stimulated by surface tension forces induced by the passage of a liquid-air

  5. Feasibility of active solar water heating systems with evacuated tube collector at different operational water temperatures

    International Nuclear Information System (INIS)

    Mazarrón, Fernando R.; Porras-Prieto, Carlos Javier; García, José Luis; Benavente, Rosa María

    2016-01-01

    Highlights: • Analysis of the feasibility of an active solar water-heating system. • Profitability decreases as the required water temperature increases. • The number of collectors that maximizes profitability depends on the required temperature. • Investment in a properly sized system generates savings between 23% and 15%. • Fuel consumption can be reduced by 70%. - Abstract: With rapid advancements in society, higher water temperatures are needed in a number of applications. The demand for hot water presents a great variability with water required at different temperatures. In this study, the design, installation, and evaluation of a solar water heating system with evacuated tube collector and active circulation has been carried out. The main objective is to analyze how the required tank water temperature affects the useful energy that the system is capable of delivering, and consequently its profitability. The results show how the energy that is collected and delivered to the tank decreases with increasing the required temperature due to a lower performance of the collector and losses in the pipes. The annual system efficiency reaches average values of 66%, 64%, 61%, 56%, and 55% for required temperatures of 40 °C, 50 °C, 60 °C, 70 °C, and 80 °C. As a result, profitability decreases as temperature increases. The useful energy, and therefore the profitability, will decrease if the demand is not distributed throughout the day or focused on the end of the day. The system’s profitability was determined in two cases: considering maximum profitability of the system, assuming 100% utilization of useful energy (scenario 1); assuming a particular demand, considering that on many days all the useful energy the system can supply is not used (scenario 2). The analysis shows that through proper sizing of the system, optimizing the number of solar collectors, the investment in the solar system can be profitable with similar profitability values in the two

  6. Study of an improved integrated collector-storage solar water heater combined with the photovoltaic cells

    International Nuclear Information System (INIS)

    Ziapour, Behrooz M.; Palideh, Vahid; Mohammadnia, Ali

    2014-01-01

    Highlights: • Simulation of an enhanced ICSSWH system combined with PV panel was conducted. • The present model dose not uses any photovoltaic driven water pump. • High packing factor and tank water mass are caused to high PVT system efficiency. • Larger area of the collector is resulted to lower total PVT system efficiency. - Abstract: A photovoltaic–thermal (PVT) module is a combination of a photovoltaic (PV) panel and a thermal collector for co-generation of heat and electricity. An integrated collector-storage solar water heater (ICSSWH) system, due to its simple and compact structure, offers a promising approach for the solar water heating in the varied climates. The combination of the ICSSWH system with a PV solar system has not been reported. In this paper, simulation of an enhanced ICSSWH system combined with the PV panel has been conducted. The proposed design acts passive. Therefore, it does not use any photovoltaic driven water pump to maintain a flow of water inside the collector. The effects of the solar cell packing factor, the tank water mass and the collector area on the performance of the present PVT system have been investigated. The simulation results showed that the high solar cell packing factor and the tank water mass are caused to the high total PVT system efficiency. Also, larger area of the collector is resulted to lower total PVT system efficiency

  7. A Review on Photovoltaic-Thermal (PV-T) Air and Water Collectors

    International Nuclear Information System (INIS)

    Avezov, R.R.; Akhatov, J. S.; Avezova, N. R.

    2011-01-01

    This paper presents the state-of-the-art on photovoltaic-thermal PV-T collectors. There are presented two main classification groups: -Air and -Water PV-Thermal collectors, design and performance evaluation, comparison of the findings obtained by various researchers. The review also covers the description of different designs of air and water PV-T collectors, the results of theoretical and experimental works, focused to optimization of the technical and economical performances in terms of electrical as well as thermal outputs. (authors)

  8. Solar power from the supermarket. Water heating, space heating and air conditioning with solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    1976-08-01

    The different ways of utilizing solar energy are discussed. So far, top water heating is still the most practicable and most economical solution. Model houses with solar collectors, built by BBC and Philips, are dealt with in particular.

  9. Studies of flat-plate solar air collectors with absorber plates made of amorphous silicon photovoltaic modules; Amorphous taiyo denchi module wo shunetsuban to shita heibangata kukishiki shunetsuki no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K; Ito, S; Miura, N [Kanagawa Institute of Technology, Kanagawa (Japan)

    1996-10-27

    A light/heat hybrid air type heat collector has been developed in which heat is collected by solar cell panels. In Type 1 heat collector provided with a glass cover, two modules are connected in series and placed under a glass cover to serve as a heat collecting plate, each module built of a steel plate and two thin-film amorphous solar cells bonded to the steel plate. Air runs under the heat collecting plate. Type 2 heat collector is a Type 1 heat collector minus the glass cover. Air is taken in by a fan, runs in a vinyl chloride tube, and then through the heat collector where it is heated by the sun, and goes out at the exit. Heat collecting performance was subjected to theoretical analysis. This heat collector approximated in point of heat collection a model using a board painted black, which means that the new type functions effectively as an air-type heat collector. Operating as a photovoltaic power generator, the covered type generated approximately 20% less than the uncovered type under 800W/m{sup 2} insolation conditions. Type 1 has been in service for five months, and Type 2 for 2 months. At present, both are free of troubles such as deformation and the amorphous solar cell modules have deteriorated but a little. 4 refs., 9 figs.

  10. Reduction of Fire Hazard in Materials for Irrigators and Water Collectors in Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, N. V.; Konstantinova, N. I., E-mail: konstantinova-n@inbox.ru [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation); Gordon, E. P. [Research and Production Center “Kaustik” (Russian Federation); Poedintsev, E. A. [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation)

    2016-09-15

    A way of reducing the fire hazard of PVC film used to make cooling-tower irrigators and water collectors is examined. A new generation of fire retardant, nanostructured magnesium hydroxide, is used to impart fire retardant properties. The fabrication technology is optimized with a roller-calendering manufacturing technique, and the permissible ranges of fire hazard indicators for materials in irrigators and water collectors are determined.

  11. Validation of a simple dynamic thermal performance characterization model based on the piston flow concept for flat-plate solar collectors

    DEFF Research Database (Denmark)

    Deng, Jie; Yang, Ming; Ma, Rongjiang

    2016-01-01

    dynamic model based on the first-order difference method is compared to that of the numerical solution of the collector ordinary differential equation (ODE) model using the fourth-order Runge-Kutta method. The improved thermal inertia model (TIM) on the basis of closed-form solution presented by Deng et....... (2012) for the model turns out to be the collector static response time constant τC by analytical derivation. The nonlinear least squares method is applied to determine the characteristic parameters of a flat-plate solar air collector previously tested by the authors. Then the obtained parameters...

  12. Rising hopes for vacuum tube collectors

    Energy Technology Data Exchange (ETDEWEB)

    Godolphin, D.

    1982-06-01

    The performance, feasibility and use of vacuum tube solar collectors for domestic hot water (DHW) systems are discussed. An introduction to the design of vacuum tube collectors is presented and comparisons are made with flat plate collectors in terms of effectiveness in DHW applications and cost. The use of vacuum tube collectors is well established for high temperature use such as process heat and absorption cooling applications; there is considerable debate concerning their use in DHW and these arguments are presented. It is pointed out that the accepted standardized comparison test (ASHRAE 93-77) is apparently biased towards the flat plate collectors in direct comparisons of collector efficiencies. Recent developments among manufacturers with regard to vacuum tube collectors and their thinking (pro and con) are discussed in some detail. Breakage and other problems are pointed out although advocates look ahead to lower costs, higher efficiencies, and broader markets (particularly in DHW). It is concluded by some that flat plate collector technology has reached its peak and that vacuum tube collectors will be very prominent in the future. (MJJ)

  13. Comparing between predicted output temperature of flat-plate solar collector and experimental results: computational fluid dynamics and artificial neural network

    Directory of Open Access Journals (Sweden)

    F Nadi

    2017-05-01

    Full Text Available Introduction The significant of solar energy as a renewable energy source, clean and without damage to the environment, for the production of electricity and heat is of great importance. Furthermore, due to the oil crisis as well as reducing the cost of home heating by 70%, solar energy in the past two decades has been a favorite of many researchers. Solar collectors are devices for collecting solar radiant energy through which this energy is converted into heat and then heat is transferred to a fluid (usually air or water. Therefore, a key component in performance improvement of solar heating system is a solar collector optimization under different testing conditions. However, estimation of output parameters under different testing conditions is costly, time consuming and mostly impossible. As a result, smart use of neural networks as well as CFD (computational fluid dynamics to predict the properties with which desired output would have been acquired is valuable. To the best of our knowledge, there are no any studies that compare experimental results with CFD and ANN. Materials and Methods A corrugated galvanized iron sheet of 2 m length, 1 m wide and 0.5 mm in thickness was used as an absorber plate for absorbing the incident solar radiation (Fig. 1 and 2. Corrugations in absorber were caused turbulent air and improved heat transfer coefficient. Computational fluid dynamics K-ε turbulence model was used for simulation. The following assumptions are made in the analysis. (1 Air is a continuous medium and incompressible. (2 The flow is steady and possesses have turbulent flow characteristics, due to the high velocity of flow. (3 The thermal-physical properties of the absorber sheet and the absorber tube are constant with respect to the operating temperature. (4 The bottom side of the absorber tube and the absorber plate are assumed to be adiabatic. Artificial neural network In this research a one-hidden-layer feed-forward network based on the

  14. Side-by-side comparisons of evacuated compound parabolic concentrator and flat plate solar collector systems at temperatures of 90 to 100C

    Science.gov (United States)

    Allen, J. W.; Schertz, W. W.; Wantroba, A. S.

    1987-03-01

    This collector system study is an extension of a previous system study in which Argonne National Laboratory (ANL) compared the performance of three solar energy systems operated side by side for over a year. In the present system study, four solar energy systems were operated side by side for part of a year. Two of the collector systems used commercially available compound parabolic concentrator (CPC) collectors, one used a commercially available flat plate collector, and one used an experimental CPC collector built by The University of Chicago. The collectors were mounted in fixed positions; they did not track the Sun, and their tilt angles were not seasonally adjusted. All of the collector arrays faced south and were tilted at 42 deg with respect to the horizon (to match the 42 deg N latitude at ANL). All four collector systems started each day with their storage temperatures at 90 C. During the day, each system was operated by its own solar controller. At the end of the day, the tanks were mixed and the temperature changes in the tanks were measured. The change in storage energy was calculated from the temperature change, the heat capacity of the storage system, and the pump energy.

  15. Open fibre reinforced plastic (FRP) flat plate collector (FPC) and spray network systems for augmenting the evaporation rate of tannery effluent (soak liquor)

    International Nuclear Information System (INIS)

    Srithar, K.; Mani, A.

    2007-01-01

    Presently, tanneries in Tamilnadu, India are required to segregate the effluent of soaking and pickling sections from other wastewater streams and send it to shallow solar pans for evaporation to avoid land pollution. A large area of solar pans is required for evaporating the water in the effluent at salt concentration in the range of 4-5%. An experimental study has been made by using fibre reinforced plastic flat plate collector (FRP-FPC) and spray system in a pilot plant with a capacity to handle 5000 l per day, which increases the evaporation rate. After increasing the salt concentration level to near saturation limit, the concentrated liquid was sent to conventional solar pans for its continued evaporation and recovery of salt. In this improved system, the rate of evaporation was found to be 30-40% more than that in the conventional solar pans. The performance is compared with the theoretically simulated performance. (author)

  16. Numerical analysis and experimental validation of heat transfer characteristic for flat-plate solar air collector

    International Nuclear Information System (INIS)

    Hung, Tzu-Chen; Huang, Tsung-Jie; Lee, Duen-Sheng; Lin, Chih-Hung; Pei, Bau-Shei; Li, Zeng-Yao

    2017-01-01

    Highlights: • Various types of solar air collectors are discussed. • CFD has been used to validate the characteristics of heat transfer. • Solar Ray Tracing has been successfully used for thermal radiation flux. - Abstract: This study combines both concepts of solar ventilation technology and solar air collector. This is a quite innovative and potential facility to effectively use thermal energy and reduce the accumulation of heat in the indoor space simultaneously. The purpose of this study is to create a prototype and implement the experiments. Computational fluid dynamics (CFD) approach is employed to validate the characteristics of the flow and heat transfer. For the accuracy of numerical predictions, the method of Solar Ray Tracing was used for thermal radiation flux as boundary condition on the wall. The local heat transfer correlation was investigated to predict surrounding wind speed upon device cover. Three sorts of glasses and several aspect ratios of flow channels have been compared to conclude the optimal configuration. In addition, four important factors, such as the stagnant layer thickness, emissivity on the illustrated surface, mass flow rate and the height of the device, are also considered and discussed in detail. The result showed that the optimal design is dominated by the combination of an aspect ratio of 50 mm:10 mm, and appropriate mass flow rate to the height of the device. The present work on thermal energy collection can assist us in designing a powerful solar air collector in some potential applications.

  17. Diseño de un colector solar de placa plana; Design of a Solar Flat Plate Collector

    Directory of Open Access Journals (Sweden)

    Jeovany Rafael Rodríguez Mejía

    2015-12-01

    Full Text Available En el presente artículo se integra el uso de un software de diseño mecánico y un algoritmo de simulación de la operación de un colector solar de placa plana, con el objetivo de simplificar el proceso de diseño y manufactura de este último. Se exponen los resultados de la simulación de la operación del colector solar considerando diferentes combinaciones en los parámetros de los materiales utilizados, tales como sus propiedades y características físico químicas, además de la variación de las dimensiones del sistema adiseñar. Finalmente en el artículo se evalúa la operación de un colector solar para las condiciones climatológicas típicas de la irradiancia, velocidad de viento y temperatura ambiente a partir de una serie de curvas sinusoidales, típicas de Cuba, validándose la viabilidad del algoritmo como apoyo en la etapa de diseño y selección de materiales.In this article the use of mechanical design software and an algorithm for simulating the operation of a flat plate solar collector, with the objective of simplifying the process of design and manufacture of the latter isintegrated. The simulation results of the operation of the solar collector considering different combinations in the parameters of the materials used, such as its physicochemical properties and features in addition to thevariation of the dimensions of the system design are set. The article finally evaluates the operation of a solar collector for typical climatic conditions of irradiance, wind speed and ambient temperature from a series ofsinusoidal, typical Cuba curves is evaluated, validating the feasibility of the algorithm as support in step design and material selection.

  18. Analysis of the thermal performance of a solar heating system using a collector with absorbing surface in plates coated with PVC; Analise do desempenho termico de um sistema de aquecimento solar utilizando coletor com superficie absorvedora em chapas de forro de PVC

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Edmilson Pedreira dos

    2009-08-15

    It is presented a solar collector to be used in a system for heating bath water, whose main characteristic is its low cost. The collector consists of five plates of PVC with 10 mm thick, 200 mm wide and 1400 mm length, with ao area equal to 1,4 square meters. The plates were connected in parallel to the ends of PVC tubes of 40 mm diameter and 32 mm diameter. The plates were coated on one side with aluminum sheets of soft drinks and beers cans open. The system worked on a thermosyphon and was tested in two configurations: the plates uncoated and coated with aluminum material, to determine the influence of material on the efficiency of the collector. For both configurations was used EPS plates below the surface to minimize heat losses from the bottom. The thermal reservoir of the heating system is, also, alternative and of low cost, since it was constructed from a polyethylene tank for storing water, with volume of 150 end 200 liters. It will be presented the thermal efficiency, heat loss, water temperature of the thermal reservoir at the end of the process and simulation of baths for a house with four residents. It will be demonstrated the thermal, economic and material viability of the proposed collector, whose main innovation is the use of recyclable materials, cans of beer and soft drinks, to increase the temperature of the absorber plate. (author)

  19. COMBINED UNCOVERED SHEET-AND-TUBE PVT-COLLECTOR SYSTEM WITH BUILT-IN STORAGE WATER HEATER

    Directory of Open Access Journals (Sweden)

    Muhammad Abid

    2012-02-01

    Full Text Available This work describes the design and investigation of a simple combined uncovered sheet-and-tube photo-voltaic-thermal (PVT collector system. The PVT-collector system consists of a support, standard PV module (1.22x0.305m, area=0.37m2, fill factor=0.75, sheet-and-tube water collector and storage tank-heater. The collector was fixed under PV module. Inclination angle of the PVT-collector to the horizontal plane was 45 degree. The storage tank-heater played double role i.e. for storage of hot water and for water heating. The PVT-collector system could work in the fixed and tracking modes of operation. During investigations of PVT-collector in natural conditions, solar irradiance, voltage and current of PV module, ambient temperature and water temperature in storage tank were measured. Average thermal and electrical powers of the PVT-collector system at the tracking mode of operation observed were 39W and 21W, with efficiencies of 15% and 8% respectively at the input power of 260W. The maximum temperature of the water obtained was 42oC. The system was observed efficient for low-temperature applications. The PVT-collector system may be used as a prototype for design of PVT-collector system for domestic application, teaching aid and for demonstration purposes.

  20. Detachment of colloidal particles from collector surfaces with different electrostatic charge and hydrophobicity by attachment to air bubbles in a parallel plate flow chamber

    NARCIS (Netherlands)

    Suarez, CG; van der Mei, HC; Busscher, HJ

    1999-01-01

    The detachment of polystyrene particles adhering to collector surfaces with different electrostatic charge and hydrophobicity by attachment to a passing air bubble has been studied in a parallel plate flow chamber. Particle detachment decreased linearly with increasing air bubble velocity and

  1. Air bubble-induced detachment of positively and negatively charged polystyrene particles from collector surfaces in a parallel-plate flow chamber

    NARCIS (Netherlands)

    Gomez-Suarez, C; Van der Mei, HC; Busscher, HJ

    2000-01-01

    Electrostatic interactions between colloidal particles and collector surfaces were found tcr be important in particle detachment as induced by the passage of air bubbles in a parallel-plate Row chamber. Electrostatic interactions between adhering particles and passing air bubbles, however, a-ere

  2. Imitation experiment for water-treatment by heat of solar collector and hot pump

    International Nuclear Information System (INIS)

    Liao Yuanzong; Liu Shuqing; Pang Heding; Zhao Zhongxin; Zhang Biguang; Wang Xiping; Huo Guangqing

    1997-01-01

    The author presents an imitation experiment in which solar collector and hot pump are jointed for supplying heat to evaporate cleaned water and diffuse it into air. The effects of the temperature and the quantity of supplying air, and circumstance conditions on evaporation quantity are studied. The ratio of evaporating quantity to consuming energy, the efficiency of evaporation, average efficiency of solar collector and supplying heat coefficient of heat pump are measured. The experiment shows that this supplying heat model is practicable, economic and efficient for treating cleaned water

  3. Simulation of solar lithium bromide-water absorption cooling system with parabolic trough collector

    International Nuclear Information System (INIS)

    Mazloumi, M.; Naghashzadegan, M.; Javaherdeh, K.

    2008-01-01

    Ahwaz is one of the sweltering cities in Iran where an enormous amount of energy is being consumed to cool residential places in a year. The aim of this research is to simulate a solar single effect lithium bromide-water absorption cooling system in Ahwaz. The solar energy is absorbed by a horizontal N-S parabolic trough collector and stored in an insulated thermal storage tank. The system has been designed to supply the cooling load of a typical house where the cooling load peak is about 17.5 kW (5 tons of refrigeration), which occurs in July. A thermodynamic model has been used to simulate the absorption cycle. The working fluid is water, which is pumped directly to the collector. The results showed that the collector mass flow rate has a negligible effect on the minimum required collector area, but it has a significant effect on the optimum capacity of the storage tank. The minimum required collector area was about 57.6 m 2 , which could supply the cooling loads for the sunshine hours of the design day for July. The operation of the system has also been considered after sunset by saving solar energy

  4. Diseño de un colector solar de placa plana; Design of a solar fl at plate collector

    Directory of Open Access Journals (Sweden)

    Jeovany Rafael Rodríguez Mejía

    2016-02-01

    Full Text Available En el presente artículo se integra el uso de un software de dis eño mecánico y un algoritmo de simulación de la operación de un colector solar de placa plana, con el objeti vo de simplificar el proceso de diseño y manufactura de este último. Se exponen los resultados de la sim ulación de la operación del colector solar considerando diferentes combinaciones en los parámetros de los materiales utilizados, tales como sus propiedades y características físico químicas, además de la var iación de las dimensiones del sistema a diseñar. Finalmente en el artículo se evalúa la operación de un colector solar para las condiciones climatológicas típicas de la irradiancia, velocidad de viento y temperatura ambiente a partir de una serie de curvas sinusoidales, típicas de Cuba, validándose la viabilidad del algoritmo como apoyo en la etapa de diseño y selección de materiales. In this article the use of mechanical design software and an al gorithm for simulating the operation of a flat plate solar collector, with the objective of simplifying the pr ocess of design and manufacture of the latter is integrated. The simulation results of the operation of the sola r collector considering different combinations in the parameters of the materials used, such as its physicochemic al properties and features in addition to the variation of the dimensions of the system design are set. The a rticle finally evaluates the operation of a solar collector for typical climatic conditions of irradiance, wind s peed and ambient temperature from a series of sinusoidal, typical Cuba curves is evaluated, validating the fe asibility of the algorithm as support in step design and material selection.

  5. A waveshifter light collector for a water Cherenkov detector

    International Nuclear Information System (INIS)

    Claus, R.; Sulak, L.; Ciocio, A.; Stone, J.L.; Seidel, S.; Casper, D.; Bionta, R.M.; Park, H.S.; Wuest, C.; Blewitt, G.; Bratton, C.B.; Dye, S.T.; Learned, J.G.; Errede, S.; Foster, G.W.; Gajewski, W.; Matthews, J.; Sinclair, D.; Thornton, G.; Van Der Velde, J.C.; Ganezer, K.S.; Haines, T.J.; Kropp, W.R.; Price, L.; Reines, F.; Schultz, J.; Sobel, H.W.; Svoboda, R.; Goldhaber, M.; Jones, T.W.; Kielczewska, D.; Losecco, J.M.; Shumard, E.

    1987-01-01

    A device has been developed which is capable of doubling the light collection capability of a 5 inch hemispherical photomultiplier tube. Known as a 'waveshifter plate', its geometry is adaptable to various applications. Its marginal cost is small with respect to that of a phototube, it is readily removable, and it has minimum effect upon dark noise and timing resolution. (orig.)

  6. Thermo-economic optimization of a hybrid solar district heating plant with flat plate collectors and parabolic trough collectors in series

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2018-01-01

    heating network in this study. The results also show that parabolic trough collectors are economically feasible for district heating networks in Denmark. The generic and multivariable levelized cost of heat method can guide engineers and designers on the design, construction and control of large...... to optimize the hybrid solar district heating systems based on levelized cost of heat. It is found that the lowest net levelized cost of heat of hybrid solar heating plants could reach about 0.36 DKK/kWh. The system levelized cost of heat can be reduced by 5–9% by use of solar collectors in the district...

  7. Primary collector wall local temperature fluctuations in the area of water-steam phase boundary

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O.; Klinga, J.; Simo, T. [Energovyzkum Ltd., Brno (Switzerland)

    1995-12-31

    A limited number of temperature sensors could be installed at the primary collector surface in the area of water - steam phase boundary. The surface temperatures as well WWER 440 steam generator process data were measured and stored for a long time and off-line evaluated. Selected results are presented in the paper. (orig.). 2 refs.

  8. Primary collector wall local temperature fluctuations in the area of water-steam phase boundary

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O; Klinga, J; Simo, T [Energovyzkum Ltd., Brno (Switzerland)

    1996-12-31

    A limited number of temperature sensors could be installed at the primary collector surface in the area of water - steam phase boundary. The surface temperatures as well WWER 440 steam generator process data were measured and stored for a long time and off-line evaluated. Selected results are presented in the paper. (orig.). 2 refs.

  9. PERFORMANCE CHARACTERISTICS OF PARABOLIC SOLAR COLLECTOR WATER HEATER SYSTEM FITTED WITH NAIL TWISTED TAPES ABSORBER

    Directory of Open Access Journals (Sweden)

    K. SYED JAFAR

    2017-03-01

    Full Text Available In this paper, the experimental heat transfer, friction loss and thermal performance data for water flowing through the absorber tube fitted with two different twisted tape configurations in parabolic trough collector (PTC are presented. In the present work, a relative experimental study is carried out to investigate the performance of a PTC influenced by heat transfer through fluidabsorber wall mixing mechanism. The major findings of this experiment show that heat transport enhancement in the nail twisted tape collector perform significantly better than plain twisted tapes and also show that the smallest twisted tape ratio enhances the system performance remarkably maximizing the collector efficiency. The results suggest that the twisted tape and nail twisted tape would be a better option for high thermal energy collection in laminar region of the PTC system.

  10. Numerical model of simulation for solar collector of water heating; Modelo de simulaco numerica para colector solar de aquecimento de agua

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A. C. G. C.; Dutra, J. C. C.; Henriquez, J. R.; Michalewicz, J. S.

    2008-07-01

    Before being installed a solar heater, It must be tested, numerical or experimentally to get his characteristic equation, which is the efficiency curve, plotted as a function on the temperature of entry and solar incident radiation on the collector. In this work was developed a tool for numerical simulation of heating water flat-plate solar collectors. This tool has been developed from a mathematical model which is composed of a system of equations. In the model are included equations of balance energy for the collector, equation of the first law, the law of cooling equation of Newton, convective heat transfer coefficient correlations, equations for calculating the solar incident radiation, and one equation that calculates of the water flow due to the siphon effect. The solution of the equations system was obtained by the multidimensional version of the Newton-Raphson method. the model was validated with experimental data from literature. The results shows, that it is a very interesting tool to simulate efficiency curve of the solar collector. (Author)

  11. Solar Heating Systems with Evacuated Tubular Solar Collector

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1998-01-01

    Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...... carried out, employing both laboratory test and theoretical calculations. The collectors were tested in a small solar domestic hot water (SDHW) system in a laboratory test facility under realistic conditions. The yearly thermal performance of solar heating systems with these evacuated tubular collectors......, as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat...

  12. PERFORMANCE OF EVACUATED TUBE SOLAR COLLECTOR USING WATER-BASED TITANIUM OXIDE NANOFLUID

    Directory of Open Access Journals (Sweden)

    M. Mahendran

    2012-12-01

    Full Text Available Experiments are undertaken to determine the efficiency of an evacuated tube solar collector using water-based Titanium Oxide (TiO2 nanofluid at the Pekan Campus (3˚32’ N, 103˚25’ E, Faculty of Mechanical Engineering, University Malaysia Pahang, for the conversion of solar thermal energy. Malaysia lies in the equatorial zone with an average daily solar insolation of more than 900 W/m², which can reach a maximum of 1200 W/m² for most of the year. Traditionally water is pumped through the collector at an optimum flow rate, for the extraction of solar thermal energy. If the outlet temperature of the water is high, further circulation of the water through the collector is useless. This is due to the low thermal conductivity of water of 0.6 W/m.K compared to metals which is many orders higher. Hence it is necessary to reduce the surface temperature either by pumping water at a higher flow rate or by enhancing the fluid’s properties by the dispersion of nanoparticles. Pumping water at higher flow rates is not advantageous as the overall efficiency of the system is lowered. Liquids in which nanosized particles of metal or their oxides are dispersed in a base liquid such as water are known as 'Nanofluids'. This results in higher values of thermal conductivity compared to the base liquid. The thermal conductivity increases with the concentration and temperature of the nanofluid. The increase in thermal conductivity with temperature is advantageous for application in collectors as the solar insolation varies throughout the day, with a minimum in the morning reaching a maximum at 2.00p.m and reducing thereafter. The efficiency of the collector estimated using a TiO2 nanofluid of 0.3% concentration is about 0.73, compared to water which is about 0.58. The efficiency is enhanced by 16.7% maximum with 30–50nm sized TiO2 nanoparticles dispersed in the water, compared to the system working solely with water. The flow rate is fixed at 2.7 liters per

  13. An experimental study of the mass flow rates effect on flat-plate solar water heater performance using Al2O3/water nanofluid

    Directory of Open Access Journals (Sweden)

    Prakasam Michael Joseph Stalin

    2017-01-01

    Full Text Available In the present work, flat plate solar water heating system has been designed and fabricated accommodating 2 m2 area of solar collector and 0.12 m2 surface area of the heat exchanger using Al2O3/water nanofluid as the working fluid in order to evaluate the performance efficiency in the forced circulation mode. The instantaneous efficiency of solar collector is calculated by taking lower volume fraction of 0.01% with average particle size of 25 nm with and without Triton X-100 surfactant and varying the flow rate from 1 L per minute to 3 L per minute, as per ASHRAE standard. The experimental results show that utilizing Al2O3/water nanofluid with mass flow rate at 2 L per minute increases the collector efficiency by 14.3% when compared to distilled water as the working medium.

  14. Effect of the Dust on the Performance of Solar Water Collectors in Iraq

    Directory of Open Access Journals (Sweden)

    Omer Khalil Ahmed

    2016-02-01

    Full Text Available There is little research about it in present literatures in Iraq. So the effect of dust accumulation on the performance of conventional of solar collectors is analyzed. The experimental study was carried out mainly on a flat solar collector, which comprised the major part of this work. According to the experimental results obtained, there is a limited decrease in the instantaneous efficiency which was 1.6 % for the dirty collector. At load condition, the outlet temperature reaches a maximum value of 43.85oC at 12 noon without dust on the front glass and 33.7 oC in the presence of the dust. The instantaneous efficiency reaches its maximum value of 49.74 % at 12 noon without dust and 48.94% with dust after that the efficiency was decreased. The variation of useful transferred energy closely follows the variation of solar intensity and reaches its maximum value of 690 W/m2 at 12 noon in the presence of the dust for this particular day. It is also observed that, at the second half of the day, there is a large decrease in the instantaneous efficiency resulting from a large reduction in the useful energy transferred. Therefore, for Iraqi places, daily cleaning of the glass covers is strictly recommended as part of the maintenance works but the equipment should be cleaned immediately after a dust storm to keep the collector efficient. Article History: Received August 16, 2015; Received in revised form Nov 17, 2015; Accepted Dec 19, 2015; Available onlineHow to Cite This Article: Ahmed, O.K (2016. Effect of the Dust on the Performance of Solar Water Collectors in Iraq. Int. Journal of Renewable Energy Development, 5(1, 65-72.http://dx.doi.org/10.14710/ijred.5.1.65-72 

  15. Estimation of solar collector area for water heating in buildings of Malaysia

    Science.gov (United States)

    Manoj Kumar, Nallapaneni; Sudhakar, K.; Samykano, M.

    2018-04-01

    Solar thermal energy (STE) utilization for water heating at various sectorial levels became popular and still growing especially for buildings in the residential area. This paper aims to study and identify the solar collector area needed based on the user requirements in an efficient manner. A step by step mathematical approach is followed to estimate the area in Sq. m. Four different cases each having different hot water temperatures (45°, 50°C, 55°C, and 60°C) delivered by the solar water heating system (SWHS) for typical residential application at Kuala Lumpur City, Malaysia is analysed for the share of hot and cold water mix. As the hot water temperature levels increased the share of cold water mix is increased to satisfy the user requirement temperature, i.e. 40°C. It is also observed that as the share of hot water mix is reduced, the collector area can also be reduced. Following this methodology at the installation stage would help both the user and installers in the effective use of the solar resource.

  16. Solar radiation for sea-water desalination and electric power generation via vacuum solar collectors

    International Nuclear Information System (INIS)

    Mottinelli, L.; Reali, M.; El-Nashar, A.M.; Giusiano, F.; Vigotti, R.

    1996-01-01

    The present report concerns the energetic potential of vacuum solar which are rather versatile and efficient devices for converting solar energy into thermal energy. Two main energetic applications have been analysed: the first one for a solar sea water desalination plant which has been operated in Abu Dhabi for the past ten years, the other for a conceptual solar thermoelectric-power plant having a fair thermodynamic efficiency (15-20%). A simple technology for the manufacture of vacuum solar collectors in a standard mechanical shop is being developed in collaboration between ENEL Sp A (DSR-CRIS, Milano) and WED (Abu Dhabi). Such technology should have an important economy-saving potential per se and would also make repair and substitution operations simple enough for the actual operators of the vacuum solar collector system without any need of external assistance. The technic-operative-economical features of the Abu Dhabi solar desalination plant suggest that the use novel simplified vacuum solar collectors could have a considerable technic economical potential. The analysis of the conceptual solar thermo-electric-power plant focuses on its general layout and singles out key technological issues which ought to be addressed in an overall feasibility study. 5 figs., 3 tabs

  17. Analytical analysis of solar thermal collector with glass and Fresnel lens glazing

    Science.gov (United States)

    Zulkifle, Idris; Ruslan, Mohd Hafidz Hj; Othman, Mohd Yusof Hj; Ibarahim, Zahari

    2018-04-01

    Solar thermal collector is a system that converts solar radiation to heat. The heat will raise the temperature higher than the ambient temperature. Absorber and glazing are two important components in order to increase the temperature of the collector. The thermal absorber will release heat by convection and as radiation to the surrounding. These losses will be reduced by glazing. Other than that, glazing is beneficial for protecting the collector from dust and water. This study discusses about modelling of solar thermal collector effects of different mass flow rates with different glazing for V-groove flat plate solar collectors. The glazing used was the glass and linear Fresnel lens. Concentration ratio in this modelling was 1.3 for 0.1m solar collector thickness. Results show that solar collectors with linear Fresnel lens has the highest efficiency value of 71.18% compared to solar collectors with glass which has efficiency 54.10% with same operation conditions.

  18. Tracking system for solar collectors

    Science.gov (United States)

    Butler, B.

    1980-10-01

    A tracking system is provided for pivotally mounted spaced-apart solar collectors. A pair of cables is connected to spaced-apart portions of each collector, and a driver displaces the cables, thereby causing the collectors to pivot about their mounting, so as to assume the desired orientation. The collectors may be of the cylindrical type as well as the flat-plate type. Rigid spar-like linkages may be substituted for the cables. Releasable attachments of the cables to the collectors is also described, as is a fine tuning mechanism for precisely aligning each individual collector.

  19. High-Efficiency Fog Collector: Water Unidirectional Transport on Heterogeneous Rough Conical Wires.

    Science.gov (United States)

    Xu, Ting; Lin, Yucai; Zhang, Miaoxin; Shi, Weiwei; Zheng, Yongmei

    2016-12-27

    An artificial periodic roughness-gradient conical copper wire (PCCW) can be fabricated by inspiration from cactus spines and wet spider silks. PCCW can harvest fog on periodic points of the conical surface from air and transports the drops for a long distance without external force, which is attributed to dynamic as-released energy generated from drop deformation in drop coalescence, in addition to both gradients of geometric curve (inducing Laplace pressure) and periodic roughness (inducing surface energy difference). It is found that the ability of fog collection can be related to various tilt-angle wires, thus a fog collector with an array system of PCCWs is further designed to achieve a continuous process of efficient water collection. As a result, the effect of water collection on PCCWs is better than previous results. These findings are significant to develop and design materials with water collection and water transport for promising application in fogwater systems to ease the water crisis.

  20. Air/liquid collectors

    DEFF Research Database (Denmark)

    Jensen, Søren Østergaard; Olesen, Ole; Kristiansen, Finn Harken

    1997-01-01

    this kind of collectors. The modified simulation program has been used for the determination of the surplus in performance which solar heating systems with this type of solar collectors for combined preheating of ventilation air and domestic hot water will have. The simulation program and the efficiency......This report determine efficiency equations for combined air/liquid solar collectors by measurements on to different air/liquid collectors. Equations which contain all relevant informations on the solar collectors. A simulation program (Kviksol) has been modified in order to be able to handle...

  1. Thermal stratification in storage tanks of integrated collector storage solar water heaters

    International Nuclear Information System (INIS)

    Oshchepkov, M.Y.; Frid, S.E.

    2015-01-01

    To determine the influence of the shape of the tank, the installation angle, and the magnitude of the absorbed heat flux on thermal stratification in integrated collector-storage solar water heaters, numerical simulation of thermal convection in tanks of different shapes and same volume was carried out. Idealized two-dimensional models were studied; auto model stratification profiles were obtained at the constant heat flux. The shape of the tank, the pattern of the heat flux dynamics, the adiabatic mixing on the circulation rate and the degree of stratification were shown to have significant influence. (authors)

  2. Turning collectors for solar radiation

    Science.gov (United States)

    Barak, Amitzur Z.

    1976-01-01

    A device is provided for turning a solar collector about the polar axis so that the collector is directed toward the sun as the sun tracks the sky each day. It includes two heat-expansive elements and a shadow plate. In the morning a first expansive element is heated, expands to turn the collector to face the sun, while the second expansive element is shaded by the plate. In the afternoon the second element is heated, expands to turn the collector to face the sun, while the first is shaded by the plate.

  3. High-performance, low-cost solar collectors for disinfection of contaminated water.

    Science.gov (United States)

    Vidal, A; Diaz, A I

    2000-01-01

    Although the germicidal action of sunlight has long been recognized, its potential for practical applications has to be researched more thoroughly. This paper summarizes the progress made toward a commercially practical collector for solar disinfection applications. Nontracking compound parabolic collectors (CPCs), developed originally for capturing solar photons for thermal energy applications, were examined as potential solar photoreactors. A field demonstration of solar disinfection treatment using commercially manufactured solar reactors was conducted. Field tests showed successful destruction of Escherichia coli and Enterococcus faecalis and have provided data for full-scale design of water treatment systems. From above observations, a throughput value of 50 L/m2 h for the low-cost CPC reactor tested was estimated. For a 190 m3/d (0.05 MGD) facility, the estimated total costs for disinfection using UV-A is U.S. $0.19/m3 ($0.70/1000 gal). The use of near-UV sunlight to disinfect water supplies seems promising in rural communities of developing countries where treated water is unavailable.

  4. The design of an optimal fog water collector: A theoretical analysis

    Science.gov (United States)

    Regalado, Carlos M.; Ritter, Axel

    2016-09-01

    We investigate the collection efficiency of different fog water catchers assemblies (mainly flat and cylindrical structures equipped with several screens of staggered filaments) by means of parametric equations which take into consideration both impaction and aerodynamic effects. We introduce different models that vary in complexity and range of applicability, and may be used to analyze the effect that geometry, number of screens, spacing and inclination of the filament strands have on the fog water yield of the collector. Increasing the number of impacting screens, nR, is shown to improve the collection efficiency up to an optimum for nR = 3-5; beyond nR > 5 impermeability to the airflow makes the fog catcher less efficient. Geometry of the collector is shown to be relatively important: unless wind direction varies widely, the rectangular flat design is preferred over the cylindrical one, because of its larger drag, i.e. increased aerodynamic efficiency, ηa. In fact ηa is shown to be limiting, such that values over ηa > 50% are difficult to attain. By contrast the impaction efficiency, ηimp, of fog water droplets onto multiple nR parallel screens of filaments may reach theoretical values of ηimp > 80%. Inclination of the impacting screens over the vertical may slightly reduce ηimp, but this may be compensated by a reduction in flow resistance, i.e. increased aerodynamic efficiency.

  5. Design and simulation of a prototype of a small-scale solar CHP system based on evacuated flat-plate solar collectors and Organic Rankine Cycle

    International Nuclear Information System (INIS)

    Calise, Francesco; D’Accadia, Massimo Dentice; Vicidomini, Maria; Scarpellino, Marco

    2015-01-01

    Highlights: • A novel small scale solar power plant was designed and simulated. • The system is based on evacuated solar thermal collectors and an ORC system. • An average electric efficiency of 10% was found for the ORC. • The efficiency of solar collectors was found to be high in summer (>50%). • Pay-back periods lower than 5 years were estimated, in case of public funding. - Abstract: This paper presents a dynamic simulation model of a novel prototype of a 6 kW e solar power plant. The system is based on the coupling of innovative solar thermal collectors with a small Organic Rankine Cycle (ORC), simultaneously producing electric energy and low temperature heat. The novelty of the proposed system lies in the solar collector field, which is based on stationary evacuated flat-plate solar thermal collectors capable to achieve the operating temperatures typical of the concentrating solar thermal collectors. The solar field consists of about 73.5 m 2 of flat-plate evacuated solar collectors, heating a diathermic oil up to a maximum temperature of 230 °C. A diathermic oil storage tank is employed in order to mitigate the fluctuations due to the variability of solar energy availability. The hot diathermic oil exiting from the tank passes through an auxiliary gas-fired burner which provides eventual additional thermal energy. The inlet temperature of the diathermic oil entering the ORC system varies as a function of the availability of solar energy, also determining an oscillating response of the ORC. The ORC was simulated in Engineering Equation Solver (EES), using zero-dimensional energy and mass balances. The ORC model was subsequently implemented in a more general TRNSYS model, including all the remaining components of the system. The model was used to evaluate the energy and economic performance of the solar CHP system under analysis, in different climatic conditions. The results show that the efficiency of the ORC does not significantly vary during the

  6. Determination of silver in fresh water by atomic absorption spectrometry following flotation preconcentration by iron(III) collectors

    Energy Technology Data Exchange (ETDEWEB)

    Cundeva, K.; Stafilov, T. [Institute of Chemistry, Faculty of Science, St. Cyril and Methodius University, Skopje (Yugoslavia)

    1997-08-01

    Colloid precipitate flotation of silver from fresh water is applied for preconcentration and separation. Optimal conditions using hydrated iron(III) oxide and iron(III) tetramethylenedithiocarbamate as collectors were investigated. Various factors affecting the silver recovery, including collector mass, nature of the supporting electrolyte, pH of the working medium, electrokinetic potential of the collector particle surfaces, type of surfactant, induction time etc., were checked. Within the optimal pH range (5.5-6.5) silver was separated quantitatively (94.9- 100.0%) with 30 mg Fe(III) as collector. The content of silver was determined by electrothermal atomic absorption spectrometry and compared to that from inductively coupled plasma-atomic emission spectrometry. The detection limit of silver by the method described is 0.01 {mu}g/L. (orig.) With 2 figs., 3 tabs.

  7. Experimental investigation of forced-convection in a finned rhombic tube of the flat-plate solar collectors

    DEFF Research Database (Denmark)

    Taherian, Hessam; Yazdanshenas, Eshagh

    2006-01-01

    Due to scarcity of literature on forced-convection heat transfer in a solar collector with rhombic cross-section absorbing tubes, a series of experiments was arranged and conducted to determine heat transfer coefficient. In this study, a typical rhombic cross-section finned tube of flat...

  8. Heat transfer analysis and the effect of CuO/Water nanofluid on direct absorption concentrating solar collector

    International Nuclear Information System (INIS)

    Menbari, Amir; Alemrajabi, Ali Akbar; Rezaei, Amin

    2016-01-01

    Highlights: • The effect of CuO/Water on a direct absorption parabolic collector is investigated. • The power-law is used for simulating the turbulent flow into the receiver pipe. • In this collector the solar irradiance is absorbed directly and converted to heat. • Nanofluid as the working fluid improves the thermal efficiency of the collector. - Abstract: Direct absorption solar collectors (DASCs) form a new class of collectors that directly harvest sun beams via a working fluid. They offer several advantages over their conventional surface absorption counterparts such as reduced surface heat loss and increased solar irradiance absorption. The optical and thermo-physical properties of the working fluid may be improved and system efficiency may be enhanced in direct absorption solar collectors (DASCs) by introducing nanoparticles into the base fluid. The present study investigates, both analytically and experimentally, the effects of CuO/Water nanofluid on the efficiency of a direct absorption parabolic trough collector (DAPTC). The theoretical analysis of DAPTC is based on the power-law with the objective of simulating a turbulent flow into the receiver pipe. Comparison of the results obtained from the model and the experimental measurements reveals a good agreement between the two sets of data, indicating that they can be exploited to validate the numerical solution. Moreover, modeling results indicate that the average radial temperature and energy generation terms due to the solar irradiance absorbed and scattered by the nanoparticles decrease with increasing distance from the receiver pipe wall. It is also found that the solar irradiance is absorbed and converted into a significant amount of sensible heat along the length of the receiver pipe. Finally, the results of both the numerical and the experimental investigations of the DAPTC collector show that the thermal efficiency of the system improves as a result of increased nanoparticle volume fraction

  9. New collectors from all over the world

    Energy Technology Data Exchange (ETDEWEB)

    Augsten, Eva

    2008-07-01

    Flat-plate collectors are fashionable, even among customers in Shanghai, although China is considered the land of evacuated tubes. Elsewhere, fashion is also a consideration, which partly explains the switch from fin collectors to full-surface collectors. Sun and Wind Energy has put together a list of new collectors from various countries. (orig.)

  10. Integrated collector-storage solar water heater with extended storage unit

    International Nuclear Information System (INIS)

    Kumar, Rakesh; Rosen, Marc A.

    2011-01-01

    The integrated collector-storage solar water heater (ICSSWH) is one of the simplest designs of solar water heater. In ICSSWH systems the conversion of solar energy into useful heat is often simple, efficient and cost effective. To broaden the usefulness of ICSSWH systems, especially for overnight applications, numerous design modifications have been proposed and analyzed in the past. In the present investigation the storage tank of an ICSSWH is coupled with an extended storage section. The total volume of the modified ICSSWH has two sections. Section A is exposed to incoming solar radiation, while section B is insulated on all sides. An expression is developed for the natural convection flow rate in section A. The inter-related energy balances are written for each section and solved to ascertain the impact of the extended storage unit on the water temperature and the water heater efficiency. The volumes of water in the two sections are optimized to achieve a maximum water temperature at a reasonably high efficiency. The influence is investigated of inclination angle of section A on the temperature of water heater and the angle is optimized. It is determined that a volume ratio of 7/3 between sections A and B yields the maximum water temperature and efficiency in the modified solar water heater. The performance of the modified water heater is also compared with a conventional ICSSWH system under similar conditions.

  11. Collector feedwater supply and stability of the power distribution in a pressurized-water reactor

    International Nuclear Information System (INIS)

    Budnikov, V.I.; Kosolapov, S.V.; Kramerov, A.Ya.

    1980-01-01

    It is necessary to determine how the collector feedwater supply affects the disposition of the stability limits and the instability period for the power distribution in such a reactor. The main reason for the fluctuations in feedwater flow rate were shown by additional calculations with the general power regulator switched out to be due to instability on the fundamental in the neutron distribution. The power-level fluctuations are due to oscillation of the feed valve in the level regulator, and consequently to oscillations in the feedwater flow rate. If collector feed is to be employed, it is desirable to improve the response of the pressure control system for the separator drum, because under certain emergency conditions there will be a considerable fall in pressure in the separator drum. The deviation from saturation for the water in the separator drum tube is less in the second method than it is in the first, so the cavitation margin in the principal pumps may be reduced somewhat. Calculations show that this reduction will not occur if the time constant of the turbine synchronizer is about 10 sec. Also, the dynamic characteristics of the nuclear power station in these modes of feedwater supply are appreciably influenced by the parameters of the pressure-control system and the water-level control for the separator drum

  12. The effect of coupling a flat-plat collector on the solar still productivity

    International Nuclear Information System (INIS)

    Badran, O. O.; Al-Tahaineh, H. A.

    2006-01-01

    Experimental investigation to study the effect of coupling a flat plate solar collector on the productivity of solar stills was carried out. Other different parameters (i.e. water depth, direction of still, solar radiation) to enhance the productivity were also studied. Single slope solar still with mirrors fixed to its interior sides was coupled with a flat plate collector. It has been found that coupling of a solar collector with a still has increased the productivity by 56%. Also the increase of water depth has decreased the productivity, while the still productivity is found to be proportional to the solar radiation intensity.(Author)

  13. Thermal performance of an integrated collector storage solar water heater (ICSSWH) with phase change materials (PCM)

    International Nuclear Information System (INIS)

    Chaabane, Monia; Mhiri, Hatem; Bournot, Philippe

    2014-01-01

    Highlights: • We study the effect of phase change materials integration on the thermal performances of an ICSSWH. • Two kinds and tree radiuses of the PCM layer are studied and the most appropriate design is presented. • The use of phase change materials in ICSSWH is determined to reduce the night thermal losses. • Myristic acid is the most appropriate PCM for this application regarding the daily and night operation. - Abstract: In this paper, we propose a numerical study of an integrated collector storage solar water heater (ICSSWH). Two numerical models in three-dimensional modeling are developed. The first one which describes a sensible heat storage unit (SHSU), allowing validating the numerical model. Based on the good agreement between numerical results and experimental data from literature, and as this type of solar water heater presents the disadvantage of its high night losses, we propose to integrate a phase change material (PCM) directly in the collector and to study its effect on the ICSSWH thermal performance. Indeed, a second 3D CFD model is developed and series of numerical simulations are conducted for two kind (myristic acid and RT42-graphite) and three radiuses (R = 0.2 m, R = 0.25 m and R = 0.3 m) of this PCM layer. Numerical results show that during the day-time, the latent heat storage unit (LHSU) performs better than the sensible one when myristic acid is used as PCM. Regarding the night operating of this solar system, it is found that the LHSU is more effective for both PCMs as it allows lower thermal losses and better heat preservation

  14. Biological sample collector

    Science.gov (United States)

    Murphy, Gloria A [French Camp, CA

    2010-09-07

    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  15. The impact of the hot tap water load pattern in the industrial hall on the energy yield from solar collectors

    Science.gov (United States)

    Fidorów-Kaprawyl, Natalia; Dudkiewicz, Edyta

    2017-11-01

    The systems using solar energy, popular in Poland, can be used to supply hot water for the installation used by employees of industrial halls. In manufacturing plants, employing a large number of people, the demand for hot water is practically constant throughout the year and is characterized by periodic use at the end of each work shift. Dynamics of the hot water consumption depends on the number of shifts as well as working days and holidays. Additionally the maximum hot tap water demand occurs in the whole period of installation operation. In polish climatic conditions the solar collectors' systems have the largest capacity in the summer, while in winter they need to be assisted. Beside that the supply of renewable energy is uneven and depends on weather conditions. In the paper the one-hour step analysis concerning the dependence of the load pattern of the hot tap water preparation system on the energy yield from solar collectors had been performed.

  16. No-contact method of determining average working-surface temperature of plate-type radiation-absorbing thermal exchange panels of flat solar collectors for heating heat-transfer fluid

    International Nuclear Information System (INIS)

    Avezova, N.R.; Avezov, R.R.

    2015-01-01

    A brand new no-contact method of determining the average working-surface temperature of plate-type radiation-absorbing thermal exchange panels (RATEPs) of flat solar collectors (FSCs) for heating a heat-transfer fluid (HTF) is suggested on the basis of the results of thermal tests in full-scale quasistationary conditions. (authors)

  17. Air-liquid solar collector for solar heating, combined heating and cooling, and hot water subsystems

    Science.gov (United States)

    1978-01-01

    A collection of quarterly reports consisting of the installation and layout design of the air collector system for commercial applications, completion of the preliminary design review, detailed design efforts, and preparation of the verification test plan are given. Performance specifications and performance testing of a prototype model of a two manifold, 144 tube air collector array is presented.

  18. ANALYSIS AND MODELING OF SOLAR EVAPORATOR-COLLECTOR

    Directory of Open Access Journals (Sweden)

    Zakaria Mohd. Amin

    2015-11-01

    Full Text Available Solar energy is considered a sustainable resource that poses little to no harmful effects on the environment. The performance of a solar system depends to a great extent on the collector used for the conversion of solar radiant energy to thermal energy. A solar evaporator-collector (SEC is basically an unglazed flat plate collector where refrigerants, such as R134a is used as the working fluid. As the operating temperature of the SEC is very low, it utilizes both solar irradiation and ambient energy leading to a much higher efficiency than the conventional collectors. This capability of SECs to utilize ambient energy also enables the system to operate at night. This type of collector can be locally made and is relatively much cheaper than the conventional collector.   At the National University of Singapore, the evaporator-collector was integrated to a heat pump and the performance was investigated for several thermal applications: (i water heating, (ii drying and (iii desalination. A 2-dimensional transient mathematical model of this system was developed and validated by experimental data. The present study provides a comprehensive study of performance. KEYWORDS: heat pump; evaporator-collector.

  19. Modelling of Microclimate in collectors

    DEFF Research Database (Denmark)

    Holck, Ole

    1996-01-01

    Abstract It is important to avoid condensation in solar collectors, most of all because wetness of the absorber can damage the selective surface and cause corrosion on the absorber plate. During night time the cover of collectors will cool below ambient temperature due to thermal radiation...

  20. Numerical and experimental investigation on a new type of compound parabolic concentrator solar collector

    International Nuclear Information System (INIS)

    Zheng, Wandong; Yang, Lin; Zhang, Huan; You, Shijun; Zhu, Chunguang

    2016-01-01

    Highlights: • A serpentine compound parabolic concentrator solar collector is proposed. • A mathematical model for the new collector is developed and verified by experiments. • The thermal efficiency of the collector can be up to 60.5% during the experiments. • The effects of key parameters on the thermal performance are mathematically studied. - Abstract: In order to improve the thermal efficiency, reduce the heat losses and achieve high freezing resistance of the solar device for space heating in cold regions, a new type of serpentine compound parabolic concentrator solar collector is presented in this paper, which is a combination of a compound parabolic concentrator solar collector and a flat plate solar collector. A detailed mathematical model for the new collector based on the analysis of heat transfer is developed and then solved by the software tool Matlab. The numerical results are compared with the experimental data and the maximum deviation is 8.07%, which shows a good agreement with each other. The experimental results show that the thermal efficiency of the collector can be as high as 60.5%. The model is used to predict the thermal performance of the new collector. The effects of structure and operating parameters on the thermal performance are mathematically discussed. The numerical and experimental results show that the new collector is more suitable to provide low temperature hot water for space heating in cold regions and the mathematical model will be much helpful in the designing and optimizing of the solar collectors.

  1. Energy performance of water hybrid PV/T collectors applied to combisystems of Direct Solar Floor type

    Energy Technology Data Exchange (ETDEWEB)

    Fraisse, G.; Johannes, K. [Laboratoire Optimisation de la Conception et Ingenierie de l' Environnement, Ecole Superieure d' Ingenieurs de Chambery, Campus Scientifique Savoie Technolac, 73376 Le Bourget du Lac Cedex (France); Menezo, C. [Centre de Thermique de Lyon, Domaine Scientifique de La Doua, Bat. Freyssinet, 20, Avenue A. Einstein, 69621 Villeurbanne Cedex (France)

    2007-11-15

    The integration of photovoltaic (PV) modules in buildings allows one to consider a multifunctional frame and then to reduce the cost by substitution of components. In order to limit the rise of the cell operating temperature, a photovoltaics/thermal (PV/T) collector combines a solar water heating collector and PV cells. The recovered heat energy can be used for heating systems and domestic hot water. A combination with a Direct Solar Floor is studied. Its low operating temperature level is appropriate for the operating conditions of the mono- or poly-crystalline photovoltaic modules which are selected in that study. However, for a system including a glass covered collector and localised in Macon area in France, we show that the annual photovoltaic cell efficiency is 6.8% which represents a decrease of 28% in comparison with a conventional non-integrated PV module of 9.4% annual efficiency. This is obviously due to a temperature increase related to the cover. On the other hand, we show that without a glass cover, the efficiency is 10% which is 6% better than a standard module due to the cooling effect. Moreover, in the case of a glazed PV/T collector with a conventional control system for Direct Solar Floor, the maximum temperature reached at the level of the PV modules is higher than 100{sup o}C. This is due to the oversize of the collectors during the summer when the heating needs are null, i.e. without a heated swimming pool for example. This temperature level does not allow the use of EVA resin (ethylene vinyl acetate) in PV modules due to strong risks of degradation. The current solution consists of using amorphous cells or, if we do not enhance the thermal production, uncovered PV/T collector. Further research led to water hybrid PV/T solar collectors as a one-piece component, both reliable and efficient, and including the thermal absorber, the heat exchanger and the photovoltaic functions. (author)

  2. Thermal-hydraulics of PGV-4 water volume during damage of the feedwater collector nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Logvinov, S.A.; Titov, V.F. [OKB Gidropress (Russian Federation); Notaros, U.; Lenkei, I. [NPP Paks (Hungary)

    1995-12-31

    A number of VVER-440 plants has experienced the distributing nozzles of feedwater collector being damaged due to corrosion-erosion wearing. Such phenomenon could result in feedwater redistribution within the SG inventory with undesirable consequences. The collector with damaged nozzles has to be replaced but a certain time is needed for the preparatory works. The main objective of the investigation conducted is to assess if the safe operation of SG is possible before collector replacement. It was shown that the nozzle damage as observed did not result in the dangerous disturbances of thermobydraulics as compared with the conditions existing at the initial period of operation. (orig.).

  3. Thermal-hydraulics of PGV-4 water volume during damage of the feedwater collector nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Logvinov, S A; Titov, V F [OKB Gidropress (Russian Federation); Notaros, U; Lenkei, I [NPP Paks (Hungary)

    1996-12-31

    A number of VVER-440 plants has experienced the distributing nozzles of feedwater collector being damaged due to corrosion-erosion wearing. Such phenomenon could result in feedwater redistribution within the SG inventory with undesirable consequences. The collector with damaged nozzles has to be replaced but a certain time is needed for the preparatory works. The main objective of the investigation conducted is to assess if the safe operation of SG is possible before collector replacement. It was shown that the nozzle damage as observed did not result in the dangerous disturbances of thermobydraulics as compared with the conditions existing at the initial period of operation. (orig.).

  4. Effects of solar collecting area and water flow rate on the performance of a sand bed solar collector

    International Nuclear Information System (INIS)

    Maganhar, A.L.; Memon, A.H.; Panhwar, M.I.

    2005-01-01

    The often discussed renewable sources of energy have been great interest to energy researchers and planners for quite some time. The primary of renewing all sources of energy is the sun. There have been two main problems not yet fully resolved. One is the large scale production of energy and other is the cost factor. In the present study, the cost factor is under consideration. In this regard a non-conventional solar collector using indigenous material (pit sand) as solar absorber is designed and manufactured. This paper presents the results of an investigation of the effect of solar collecting area and water flow rate on the performance of a pit sand bed solar collector especially in terms of rise in water temperature. Three pit sand solar collectors of area 1m/sup 2/ each were connected in series to enhance the collecting area and the system was tested for different flow rates. Experimental results proved that there was increase in water temperature with increase in solar collecting area an decreases in water temperature with increase in flow rate. (author)

  5. Optimum tilt angle for flat plate collectors all over the World – A declination dependence formula and comparisons of three solar radiation models

    International Nuclear Information System (INIS)

    Stanciu, Camelia; Stanciu, Dorin

    2014-01-01

    Highlights: • Monthly optimum tilt angle is predicted for North latitudes between 0° and 80°. • From practical considerations, an optimum fixed value all along the year is derived. • Three solar radiation models are compared from the point of view of total incident solar radiation density prediction. - Abstract: The paper presents a theoretical study on the optimum tilt angle for flat plate collectors at different geographical locations and different time moments over a year. The solar radiation density is estimated based on three analysis models, namely Hottel and Woertz model (the simplest), Isotropic diffuse model (Liu and Jordan model) and HDKR model (Hay–Davis–Klucker–Reindl), passing from the simplest to the most complex one. Further, the absorbed solar radiation density is computed and the optimum tilt angle is found for different geographical locations (covering the Globe latitudes). The optimum value for the tilt angle is researched for maximum incident solar radiation and also for maximum absorbed one. The results indicate that the same angle is obtained when looking for maximum incident and for maximum absorbed solar radiation. When comparing the three above mentioned models, different tilt angles are supplied by applying the Hottel and Woertz model and respectively the others two (both of them providing the same angle). Although, the predicted absorbed solar radiation is the same in the summertime for all three models, and probably overestimated by the last model in the springtime. The obtained results give an overview over the whole year operation at different geographical latitudes. When using the Hottel and Woertz model for estimating the incident solar radiation, the optimum tilt angle for a flat plate collector should be computed as simplest as β opt = φ − δ function on the latitude and declination. If a fixed value is easier to be used over a specific operation period, an optimum value is provided by this research. The novelty

  6. A Stochastic Integer Programming Model for Minimizing Cost in the Use of Rain Water Collectors for Firefighting

    Directory of Open Access Journals (Sweden)

    Luis A. Rivera-Morales

    2014-01-01

    Full Text Available In this paper we propose a stochastic integer programming optimization model to determine the optimal location and number of rain water collectors (RWCs for forest firefighting. The objective is to minimize expected total cost to control forest fires. The model is tested using a real case and several additional realistic scenarios. The impact on the solution of varying the limit on the number of RWCs, the RWC water capacity, the aircraft capacity, the water demands, and the aircraft operating cost is explored. Some observations are that the objective value improves with larger RWCs and with the use of aircraft with greater capacity.

  7. Experimental anaerobic digestion generator coupled at a plan plates solar collector; Biodigestor experimental acoplado a coletor solar de placas planas

    Energy Technology Data Exchange (ETDEWEB)

    Kaneshiro, Tsuneharu [Brasilia Univ., DF (Brazil); Venanzi, D. [Sao Paulo Univ., Sao Carlos, SP (Brazil). Escola de Engenharia; Medeiros, J.T.N. de [Rio Grande do Norte Univ., Natal, RN (Brazil)

    1987-12-31

    Analysis of results of research in course in solar energy used as heat source to anaerobic degradation in organic matter are presented; water is circulated around the generator to rise and maintain a constant process. (author). 16 refs., 2 figs

  8. A flat solar collector built from galvanized steel plate, working by thermosyphonic flow, optimized for Mexican conditions; Un colector solar plano construido de lamina de acero galvanizada, operando por flujo termosifonico, optimizado para las condiciones mexicanas

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin de Jesus, A; Olivares Ramirez, J.M.; Ramos Lopez, G.A.; Pless, R.C. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Instituto Politecnico Nacional, Unidad Queretaro (Mexico)]. E-mail: amarroquind@utsjr.edu.mx

    2009-07-15

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled types, the other one flat, which are joined by electric welding. The absorber is connected to a 198-L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m{sup 2}, about 20% smaller than comparable copper-tube-based collectors offered in the market. Temperature measurements conducted over a 30-day period gave values which were a few degrees lower than the theoretically calculated water temperatures. Momentary thermal efficiency values between 35% and 77% were observed. The water temperature achieved the tank at the end of the day averages 65 degrees Celsius in winter weather conditions in the central Mexican highland. This design of solar water heater is well suited to Mexican conditions, as it makes use of the high local intensity of the solar radiation, and as the channel shape of the ducts minimizes bursting during the rare occurrences of freezing temperatures in the region; it also has the advantage of being manufacturable at low cost from simple materials. [Spanish] Se describe el diseno, construccion y pruebas del desempeno termico de un colector solar plano para calentamiento de agua para uso domestico. La placa absorbedora se construyo de materiales facilmente asequibles: dos placas de acero galvanizado, una del tipo acanalado y la otra plana, unidas mediante soldadura de acero electrico. La placa absorbedora esta conectada a un termotanque con capacidad de 198 L, aislado con espuma de poliuretano. La superficie receptora de este prototipo es de 1.35 m{sup 2}, aproximadamente 20% mas pequena comparado con los colectores, basados en tubos de cobre, ofertados en el mercado. Mediciones de temperatura por un periodo de 30 dias, arrojaron valores

  9. Experimental study on depth of paraffin wax over floating absorber plate in built-in storage solar water heater

    Directory of Open Access Journals (Sweden)

    R Sivakumar

    2015-11-01

    Full Text Available The aim of this article is to study the effect of depth of phase change material over the absorber surface of an integrated collector-storage type flat plate solar water heater. Flat plate solar water heaters are extensively used all over the world to utilize the natural source of solar energy. In order to utilize the solar energy during off-sunshine hours, it is inevitable to store and retain solar thermal energy as long as possible. Here, phase change material is not used for heat storage, but to minimize losses during day and night time only. The depth of phase change material over a fixed depth of water in a solar thermal collector is an important geometric parameter that influences the maximum temperature rise during peak solar irradiation and hence the losses. From the results of the studies for different masses of paraffin wax phase change material layers, the optimum depth corresponding to the maximum heat gain till evening is found to be 2 mm, and the heat retention till the next day morning is found to be 4 mm.

  10. Dynamic Analysis of Plate in Water Tank

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Soo; Jeong, Kyeng Hoon; Koo, Gyeong Hoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    A pool door (Plate) is installed at the chase of the pool gate by means of an overhead crane in the building of a research reactor. The principal function of the pool door, which is located between the reactor pool and service pool, is to separate the reactor pool from the service pool for the maintenance and/or the removal of the equipment either in the reactor pool or service pool. A stress analysis for each component of the pool door was conducted against the given loads including the seismic load. Because the stresses for the analysis results were lower than the design limits for the given material, the structural integrity for the given dimension of the pool door was confirmed.

  11. Design package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    Information used to evaluate the design of the Northrup concentrating collector is presented. Included are the system performance specifications, the applications manual, and the detailed design drawings of the collector. The collector is a water/glycol/working fluid type, with a dipped galvanized steel housing, transparent acrylic Fresnel lens cover, copper absorber tube, and fiber glass insulation. It weights 98 pounds. A collector assembly includes four collector units within a tracking mount array.

  12. Design package for concentrating solar collector panels

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    Information used to evaluate the design of the Northrup concentrating collector is presented. Included are the system performance specifications, the applications manual, and the detailed design drawings of the collector. The Northrup concentrating solar collector is a water/glycol/working fluid type, dipped galvanized steel housing, transparent acrylic Fresnel lens cover, copper absorber tube, fiber glass insulation and weighs 98 pounds. The gross collector area is about 29.4/sup 2/ per collector. A collector assembly includes four collector units within a tracking mount array.

  13. Optimization study of a single-effect water–lithium bromide absorption refrigeration system powered by flat-plate collector in hot regions

    International Nuclear Information System (INIS)

    Saleh, A.; Mosa, M.

    2014-01-01

    Highlights: • A comprehensive analysis for optimizing solar absorption system in hot region. • The most important parameter to be controlled is hot source temperature. • Ensuring appropriate choice of parameters, COP of absorption unit exceeds 0.8. • Results show that solar cooling systems are promising in hot regions. • The research aims to play a vital role to promote the use of renewable energy. - Abstract: This investigation has been carried out to present a comprehensive analysis for optimizing the operation of solar absorption system in hot regions. To optimize performance of the system, the hot source temperature should be controlled in function of incident solar radiation, chilled and cooling water temperatures. With an appropriate control, these external conditions can be monitored to detect and implement the actual optimization conditions. Adopting typical values encountered in hot regions, the overall system performance takes its optimal value at temperatures between 75 and 80 °C. It was found that in designing or selecting solar collector, selective coating type is necessary to produce hot water with potential around 80–90 °C needed to optimize operation of absorption unit. By ensuring an appropriate choice of components temperatures, COP of absorption unit can exceed the value 0.8. Cooling water temperature above 40 °C reduces significantly the performance of the unit which requires, under conditions of extremely high external temperatures, dimensioning and selection of condensers and absorbers that guarantee values less than this limit

  14. Thermo-ecological optimization of a solar collector

    International Nuclear Information System (INIS)

    Szargut, J.; Stanek, W.

    2007-01-01

    The depletion of non-renewable natural exergy resources (the thermo-ecological cost) has been accepted as the objective function for thermo-ecological optimization. Its general formulation has been cited. A detailed form of the objective function has been formulated for a solar collector producing hot water for household needs. The following design parameters have been accepted as the decision variables: the collector area per unit of the heat demand, the diameter of collector pipes, the distance of the pipe axes in the collector plate. The design parameters of the internal installation (the pipes, the hot water receiver) have not been taken into account, because they are very individual. The accumulation ability of hot water comprising one day has been assumed. The objective function contains the following components: the thermo-ecological cost of copper plate, copper pipes, glass plate, steel box, thermal insulation, heat transfer liquid, electricity for driving the pump of liquid, fuel for the peak boiler. The duration curves of the flux of solar radiation and absorbed heat have been elaborated according to meteorological data and used in the calculations. The objective function for economic optimization may have a similar form, only the cost values would be different

  15. Design and testing of large fog collectors for water harvesting in Asir region, Kingdom of Saudi Arabia

    Science.gov (United States)

    Abualhamayel, H. I.; Gandhidasan, P.

    2010-07-01

    The region of Asir is located in the southwestern part of the Kingdom of Saudi Arabia between longitudes 41 - 45 E and latitudes 17 - 21 N. Known for its natural beauty and cool climate delight the visitors and the region has become a destination for tourists. One of the main problems in the Asir region is the high demand for water during tourism seasons especially in view of the rapidly growing tourism sector. Flourishing tourism in the region is challenged by the scarcity of water resources and there is urgent need to identify alternative sources of potable water. It is found that fog water collection is a viable resource and Asir region is the most suitable location for fog water harvesting. An operational fog water collection project was initiated in 2007 to provide fresh water supply. Al-Sooda, situated at an altitude of about 3,000 m, was identified as the most suitable experimental site and two large fog collectors measuring 20 m by 2 m each were erected in 2009. The distance between the two sites is about 2 km. This paper gives the methods used to select the experimental site and the design of the large fog collection system. The fog collectors are flat rectangular nets supported by a post at both ends and arranged perpendicular to the direction of the prevailing wind. The collection surface, comprising two layers of black polypropylene mesh net, is fastened laterally to the posts with a set of fastening bars. The aluminum trough located below the mesh net catches the water that runs down the net and carries it to a pipe connected to the storage tank. Because the fog collectors are long and require space for guy wires for the posts, the basic site consideration is that at least 25 m of horizontal land available for the erection. Meteorological instruments and the portable weather station are used to measure the climatic data which are recorded three times a day, namely at 7:00, 14:00 and 19:00 h. On average, yields of about 5 to 6 L/m2 per day are collected

  16. Raising of geo ecological safety of engineering collectors: the new method of assessment of water tightness of reinforced concrete blocks with basalt plastic lining

    Directory of Open Access Journals (Sweden)

    Lyapidevskaya Olga

    2017-01-01

    Full Text Available This work presents analytics ways to estimation and assessment of water tightness of reinforced concrete blocks with basalt plastic lining for increasing geo ecological safety of engineering collectors. It is proved the advisability of application basalt plastic lining instead secondary protection of concrete with hydraulic seal. The results of estimation filtration coefficient and assessment of water tightness of basalt plastic lining of engineering collectors are represented. It is carried out comparative analysis of filtration coefficient and water tightness data of basalt plastic lining and secondary protection. The geo ecological effect is proved at the expense of application of new materials and reducing breakdown events with collectors that may lead pollution of ground and subsoil water with sewage.

  17. "Water-in-salt" electrolytes enable the use of cost-effective aluminum current collectors for aqueous high-voltage batteries.

    Science.gov (United States)

    Kühnel, R-S; Reber, D; Remhof, A; Figi, R; Bleiner, D; Battaglia, C

    2016-08-16

    The extended electrochemical stability window offered by highly concentrated electrolytes allows the operation of aqueous batteries at voltages significantly above the thermodynamic stability limit of water, at which the stability of the current collector potentially limits the cell voltage. Here we report the observation of suppressed anodic dissolution of aluminum in "water-in-salt" electrolytes enabling roll-to-roll electrode fabrication for high-voltage aqueous lithium-ion batteries on cost-effective light-weight aluminum current collectors using established lithium-ion battery technology.

  18. Experimental Study On Efficiency Of Solar Collector At Nagpur India During Winter

    Directory of Open Access Journals (Sweden)

    Jayant. V. Madan

    2015-08-01

    Full Text Available Abstract In this experimental study the active solar water heating direct circulation systems the thermo siphon solar flat plate collector has been tested at Government medical college 21.15N 79.09E Nagpur Maharashtra India. The various data needed are collected from Indian metrological department and during months from November to January i.e. during the winter season the responses from the system has been studied and analyzed. The maximum temperature was obtained was around 70c and the minimum ambient temperature was 18c. The objective of the present work is to evaluate efficiency of flat plate collector in Nagpur region considering these aspects of the flat plate collector both theoretically and experimentally. A test setup is fabricated and experiments conducted to study these aspects.

  19. Cheap effective thermal solar-energy collectors

    Energy Technology Data Exchange (ETDEWEB)

    Highgate, D.J.; Probert, S.D. [Cranfield University, Bedford (United Kingdom). Dept. of Applied Energy

    1996-04-01

    A light-weight flexible solar-collector, with a wavelength-selective absorption surface and an insolation-transparent thermal-insulation protecter for its aperture, was built and tested. Its cheapness and high performance, relative to a conventional flat-plate solar-collector, provide a prima-facie case for the more widespread adoption of its design. (author)

  20. [Comparison of novel infrared heating plates and conventional warm water plates for piglets' creep areas in farrowing pens].

    Science.gov (United States)

    Strauch-Sürken, L; Wendt, M

    2015-01-01

    On a conventionally managed piglet-producing farm, novel infrared (IR) heating plates for piglets in the farrowing pens were tested for their suitability and compared with common warm-water (WW) heating plates. In total, 134 litters (summer n = 82, winter n = 52) were investigated, which were housed on IR or WW heating plates, respectively, with or without an extra cover plate (groups 1-4). To determine the influence of the different heat sources, the wound healing after castration and tail docking, the umbilical regression and the weight gain of the piglets were investigated. Additionally, the lying behavior of the piglets and the position of the sows' udder at the time of farrowing were examined with regard to the heating plates. Furthermore, the energy consumption and costs were compared. The piglets housed on IR heating plates displayed better wound healing after castration and tail docking than the piglets housed on WW plates. The best results were obtained in piglets kept on IR heating plates with an extra cover plate. In addition, significant benefits were demonstrated for the usage of IR heating plates regarding umbilical regression. The piglets kept on IR heating plates had a slightly better weight gain in summer, whereas there were no differences between groups during winter. The lying behavior in the creep areas was similar in all groups. In general, with increasing age the percentage of time piglets spent in the lying position on the plates decreased. The percentage of time lying on the plates was higher in winter than in summer. At farrowing, 74.6% of all investigated sows directed their udder towards the heating plates. With the IR heating plates, this behavior occurred significantly more often. The energy consumption (kWh) per litter was significantly lower for the IR heating plates (electric power) both in winter and summer in comparison with the WW plates (gas). The energy costs were comparable in summer, but were higher for the IR heating plates

  1. OUT Success Stories: Solar Hot Water Technology

    International Nuclear Information System (INIS)

    Clyne, R.

    2000-01-01

    Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building

  2. OUT Success Stories: Solar Hot Water Technology

    Science.gov (United States)

    Clyne, R.

    2000-08-01

    Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building.

  3. Contrasting the Views and Actions of Data Collectors and Data Consumers in a Volunteer Water Quality Monitoring Project: Implications for Project Design and Management

    Directory of Open Access Journals (Sweden)

    Caren B. Cooper

    2017-12-01

    Full Text Available Data collection or generation is the primary way that the majority of volunteers advance the scientific goals of citizen science projects, but other activities such as data consumption also may influence learning, civic, and conservation outcomes. Project designers and managers balance goals for multiple outcomes and thus need to consider the influence of all project-related activities on outcomes. In a study of the kayak-based Citizen’s Water Quality Testing (CWQT Program in New York City, we compared the characteristics, perceptions, and behaviors of those collecting and using CWQT data (data collectors and those solely using the data (data consumers. Data collectors (n = 40 and consumers (n = 24 were similar in gender and political orientation, but collectors were younger, devoted more time to the project, and experienced far more face-to-face interactions related to the project. Data collectors and consumers had similar motivations for participation, except that collectors were more likely motivated by recognition for their efforts. Lack of free time was the largest barrier to participation for both types of participants, and a significantly greater barrier for consumers. Data collectors and consumers trusted volunteer-collected data more than government-collected data. Collectors and consumers both recognized multiple scientific, environmental, and social benefits associated with the project, and both were equally likely to use volunteer-collected data for a variety of purposes, such as informing decisions about conservation and recreation. Importantly, both groups were equally likely to undertake a suite of conservation behaviors. We synthesize and expand current conceptual frameworks of citizen science participation and outcomes, highlighting the need for further study to understand mechanisms and linkages between the varied activities of citizen science projects and broader social and ecological impacts. To achieve conservation goals

  4. Dust collector

    Energy Technology Data Exchange (ETDEWEB)

    Sahourin, H.

    1988-03-22

    This invention relates to a dust collector or filter which may be used for large volume cleaning air for gases or for separating out industrial byproducts such as wood chips, sawdust, and shavings. It relies on filtration or separation using only a uniquely configured medium. A primary, but not exclusive, purpose of the invention is to enable very large throughput, capable of separating or filtering of gases containing up to three or more tons of byproduct with a minimum pressure-drop across the device. No preliminary cycloning, to remove major particulates is necessary. The collector generally comprises a continuous and integral filter medium which is suspended from a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom. 11 figs.

  5. Standardized performance tests of collectors of solar thermal energy: A selectively coated, steel collector with one transparent cover

    Science.gov (United States)

    1976-01-01

    Basic test results are presented of a flat-plate solar collector whose performance was determined in solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and coolant flow rates. Collector efficiency was correlated in terms of inlet temperature and flux level.

  6. Standardized performance tests of collectors of solar thermal energy: An evacuated flatplate copper collector with a serpentine flow distribution

    Science.gov (United States)

    Johnson, S. M.

    1976-01-01

    Basic test results are given for a flat plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and one coolant flow rate. Collector efficiency is correlated in terms of inlet temperature and flux level.

  7. Comparison of three different collectors for process heat applications

    Science.gov (United States)

    Brunold, Stefan; Frey, R.; Frei, Ulrich

    1994-09-01

    In general vacuum tube collectors are used in solar process heat systems. Another possibility is to use transparent insulated flat plate collectors. A critical point however, is that most of the common transparent insulating materials can not withstand high temperatures because they consist of plastics. Thus, temperature resistive collector covers combining a high tranmisivity with a low U-value are required. One possibility is to use capillaries made of glass instead of plastics. Measurement results of collector efficiency and incident angle modifier will be presented as well as calculated energy gains for three different collectors: a vacuum tube collector (Giordano Ind., France), a CPC vacuum tube collector (microtherm Energietechnik Germany; a new flat plate collector using glass capillary as transparent insulation (SET, Germany).

  8. Magnetic collectors

    International Nuclear Information System (INIS)

    Frew, J.D.

    1980-01-01

    A collector for use in a magnetic separator is formed by isostatically pressing a metal which is resistant to attack by acid about ferromagnetic bodies whereby to encase the bodies in the metal. In one arrangement, as shown, the bodies are encapsulated between inner and outer cylinders. In other arrangements the encapsulating metal is in the form of a tube or planar sheets. The bodies are of Fe or an oxide thereof and the acid-resistant metal parts may be of stainless steel, Au, Pt, Pa or an alloy. The magnetic separator is intended for use in removing particles from liquids during the reprocessing of nuclear fuel materials. (author)

  9. The effect of water molecules on the thiol collector interaction on the galena (PbS) and sphalerite (ZnS) surfaces: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Long, Xianhao [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Chen, Ye, E-mail: fby18@126.com [College of Resources and Metallurgy, Guangxi University, Nanning 530004 (China); Chen, Jianhua, E-mail: jhchen@gxu.edu.cn [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); College of Resources and Metallurgy, Guangxi University, Nanning 530004 (China); Xu, Zhenghe; Liu, Qingxia [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada); Du, Zheng [National Supercomputing Center in Shenzhen, Shenzhen 518055 (China)

    2016-12-15

    Highlights: • Water adsorption has a greater effect on the electron distribution of ZnS surface than PbS surface. • Water adsorption decreases the reactivity of ZnS surface atoms but improves that of PbS. • Thiol collectors cannot interact with the hydrated ZnS surface. • The hydration has little influence on the interaction of thiol collectors with PbS surface. - Abstracts: In froth flotation the molecular interaction between reagents and mineral surfaces take place at the solid liquid interface. In this paper, the effect of water molecule on the three typical thiol collectors (xanthate, dithiocarbomate and dithiophosphate) interactions at the galena (PbS) and sphalerite (ZnS) surfaces has been studied adopting density functional theory (DFT). The results suggests that the presence of water molecule shows a greater influence on the electron distribution of ZnS surface than PbS surface, and reduce the reactivity of ZnS surface atoms but improves the reactivity of PbS surface atoms during the reaction with xanthate. Water adsorption could also reduce the covalent binding between Zn and S atoms but have little influence on Pb-S bond. In the presence of water, xanthate, dithiocarbomate (DTC) and dithiophosphate (DTP) could not adsorb on the sphalerite surface. And for galena (PbS) surface, the interaction of DTP is the strongest, then the DTC and the interaction of xanthate is the weakest. These results agree well with the flotation practice.

  10. Method of forming oxide coatings. [for solar collector heating panels

    Science.gov (United States)

    Mcdonald, G. E. (Inventor)

    1983-01-01

    This invention is concerned with an improved plating process for covering a substrate with a black metal oxide film. The invention is particularly directed to making a heating panel for a solar collector. A compound is electrodeposited from an aqueous solution containing cobalt metal salts onto a metal substrate. This compound is converted during plating into a black, highly absorbing oxide coating which contains hydrated oxides. This is achieved by the inclusion of an oxidizing agent in the plating bath. The inclusion of an oxidizing agent in the plating bath is contrary to standard electroplating practice. The hydrated oxides are converted to oxides by treatment in a hot bath, such as boiling water. An oxidizing agent may be added to the hot liquid treating bath.

  11. Irreversibility analysis of non isothermal flat plate solar collectors for air heating with a dimensionless model; Analisis de las irreversibilidades en colectores solares de placas planas no isotermicos para calentamiento de aire utilizando un modelo adimensional

    Energy Technology Data Exchange (ETDEWEB)

    Bracamonte-Baran, Johane Hans; Baritto-Loreto, Miguel Leonardo [Universidad Central de Venezuela (Venezuela)]. E-mails: johanehb@gmail.com; johane.bracamonte@ucv.ve; miguel.baritto@ucv.ve

    2013-04-15

    The dimensionless model developed and validated by Baritto and Bracamonte (2012) for the thermal behavior of flat plate solar collector without glass cover is improved by adding the entropy balance equation in a dimensionless form. The model is solved for a wide range of aspect ratios and mass flow numbers. A parametric study is developed and the distribution of internal irreversibilities along the collector is analyzed. The influence of the design parameters on the entropy generation by fluid friction and heat transfer is analyzed and it is found that for certain combinations of these parameters optimal thermodynamic operation can be achieved. [Spanish] En el presente trabajo, el modelo adimensional desarrollado y validado por Baritto y Bracamonte (2012) para describir el comportamiento termico de colectores solares de placas planas sin cubierta transparente, se complementa con la ecuacion adimensional de balance de entropia para un elemento diferencial de colector solar. El modelo se resuelve para un amplio rango de valores de relaciones de aspecto y numero de flujo de masa. A partir de los resultados del modelo se desarrolla un analisis detallado de la influencia de estos parametros sobre la distribucion de irreversibilidades internas a lo largo del colector. Adicionalmente se estudia la influencia de estos parametros sobre los numeros de generacion de entropia por friccion viscosa, por transferencia de calor y total. Se encuentra que existen combinaciones de los parametros antes mencionados, para los cuales, la operacion del colector es termodinamicamente optima para numeros de flujo de masa elevados.

  12. Large Dew water collectors in a village of S-Morocco (Idouasskssou)

    Science.gov (United States)

    Lekouch, I.; Clus, O.; Durand, M.; Lanfourmi, M.; Muselli, M.; Milimouk, I.; Beysens, D.

    2010-07-01

    With precipitations close to 227 mm/year in average, the coastal region of south Morocco presents a chronically shortage of drinkable and fresh water. Since 1994, in the Mirleft area (150 km south of Agadir), inhabitants are facing a critically drought event. In the year 2007, only 49 mm of rain was recorded. However, measurements in Mirleft in the same year, showed that the dew yield was on order of 40 % of rain fall. In order to show to the local population the interest of recovering dew water in addition to rain water, a small nearby village (Idouasskssou, 8 km SE of Mirleft) was equipped with three pilot condensers of 136 m2 total surface area. In order to ensure a good integration of the project by the village inhabitants, a local organization (Association IMRJANE) collaborated to the project. A concrete tank at ground level with a flat horizontal surface, easily accessible for inhabitants and also a model for traditional Morocco terrace roofings, has been equipped with two lines of condensers (40.6 m²). All roofing materials were from local shops. Only the special radiative and hydrophilic coating was coming from non local resources (see www.opur.fr). The top of a second tank (aside the first one) was renovated and covered with a 21.2 m² two slopes steel roof, insulated and painted with the special dew coating as above. These roofs represent a condensation surface comparable to that of a very little house. A third condenser, with 73.8 m² surface area, was implemented directly on the ground, ensuring minimal work and very cheap implementation costs. Dew was collected and measured in one of the concrete tanks. The water production during 6 months, from 15-12-2008 to 31-07-2009 (137 dew events, 47 % of days) was more than 3800 L (more than 0.2 mm/dew day). It is important to note that, while the devices are specifically designed to condense dew water, they also harvest rain and fog as well, thus providing to the population a valuable water resource.

  13. COSTEAU - preheating and cooling by means of underground collectors with water circulation - case study (Perret building at Satigny, Geneva) and generalisation; COSTEAU. Prechauffage et rafraichissement par collecteurs souterrains a eau. Etude de cas (batiment Perret a Satigny, Geneve) et generalisation

    Energy Technology Data Exchange (ETDEWEB)

    Hollmuller, P.; Lachal, B.

    2003-07-01

    Since a couple of years, underground collectors with air circulation have been becoming increasingly popular as a simple means for preheating (at winter time) and cooling (at summer time) of outdoor air ahead of a ventilation system for well insulated buildings. This report considers underground collectors with water circulation used for similar purposes. They are connected to the ventilation system via an air/water heat exchanger. Starting from a case study - one-year detailed in-situ measurements and data analysis from an air-heated office building near Geneva, Switzerland - computerised simulations have been performed as a sensitivity analysis tool as well as to establish recommendations and sizing rules for planners, including cost considerations. In the case study it turned out that the water-circulated underground collector, which is installed right under the basement of this well insulated building, is in thermal contact with the basement. Its main function is to damp the daily temperature oscillation of the inlet ventilation air, bringing the expected thermal comfort improvement in the summer time. However, this underground collector is unable to collect seasonally stored heat from the ground. Hence, in the winter time the main preheating contribution arises from the series-connected heat-recovery unit from the exit air. Numerical simulations show that optimal sizing of underground collectors is essential, and that both the underground collector and the well insulated building as a physical system with thermal inertia have to be simultaneously considered in the optimization process. Optimization also has to include parasitic energy (electricity) needed by fans and pumps. As outdoor air inlet can never be flooded in the case of underground collectors with water circulation the sanitary risk encountered with air-circulated underground collectors does not exist for them. Initial investment cost for water-circulated underground collectors is higher than for a

  14. The Thermal Collector With Varied Glass Covers

    International Nuclear Information System (INIS)

    Luminosu, I.; Pop, N.

    2010-01-01

    The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

  15. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    OpenAIRE

    M. Norhafana; Ahmad Faris Ismail; Z. A. A. Majid

    2015-01-01

    Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of...

  16. Simulation of the interaction of a solar domestic hot water tank system with a compact plate heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Nizami, D.J.; Lightstone, M.F. [McMaster Univ., Hamilton, ON (Canada). Dept. of Mechanical Engineering; Harrison, S.; Cruickshank, C. [Queen' s Univ., Kingston, ON (Canada). Dept. of Mechanical and Materials Engineering

    2008-08-15

    An external natural convection heat exchanger (NCHE) was used as an alternative to forced convection for transferring energy from solar collector loops to a hot water storage tank. A computational fluid dynamics (CFD) program was used to predict interactions between the natural convection-driven side-arm heat exchanger and a hot water storage tank. A solar domestic hot water tank with a vertical compact plate natural convection heat exchanger was modelled. In addition, the heat exchanger was modelled as a section of pipe with high flow resistance and a volumetric energy source. Transient analyses were conducted and the CFD model was then compared with data obtained from laboratory experiments. Simulations were conducted on the fluid domain in order to investigate the influence of the flow on the thermal stratification in the tank, the heat transfer inside the tank, and the natural convection in the tank loop. Buoyancy for an incompressible fluid with constant fluid properties was modelled using a Boussinesq approximation. Temperature distributions were measured as a function of time. Results of the study indicated that assuming a constant thermal expansion coefficient in evaluation buoyancy forces for a wide range of operating temperatures did not result in accurate predictions. Future studies will model natural convection with a full buoyancy model. 11 refs., 2 tabs., 5 figs.

  17. Low-cost solar collectors using thin-film plastics absorbers and glazings

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, W.G.

    1980-01-01

    The design, fabrication, performance, cost, and marketing of flat plate solar collectors using plastic absorbers and glazings are described. Manufacturing cost breakdowns are given for single-glazed and double-glazed collectors. (WHK)

  18. A new concept of hybrid photovoltaic thermal (PVT) collector with natural circulation

    Science.gov (United States)

    Lu, Longsheng; Wang, Xiaowu; Wang, Shuai; Liu, Xiaokang

    2017-07-01

    Hybrid photovoltaic thermal (PVT) technology refers to the integration of a photovoltaic module into a conventional solar thermal collector. Generally, the traditional design of a PVT collector has solar cells fixed on the top surface of an absorber in a flat-plate solar thermal collector. In this work, we presented a new concept of water-based PVT collector in which solar cells were directly placed on the bottom surface of its glass cover. A dynamic numerical model of this new PVT is developed and validated by experimental tests. With numerical analysis, it is found that at same covering factor, the electricity conversion efficiency of solar cells of the new PVT exceed that of the traditional PVT by nearly 10% while its thermal efficiency is approximately 30% lower than that of the traditional PVT. When the covering factor changes from 0.05 to 1, the thermal efficiency of the new PVT drops nearly 70%. The thermal efficiency of both the new PVT and the traditional PVT rise up as the water mass in tank increases. Meanwhile, the final water temperature in tank of the traditional PVT collector declines more than 17 °C, whereas that of the new PVT declines less than 6 °C, when the water mass increases from 100 to 300 kg.

  19. Experiences with the ASDEX neutralizer plates and construction of water-cooled plates for long-pulse heating

    International Nuclear Information System (INIS)

    Rapp, H.; Niedermeyer, H.; Kornherr, M.

    1987-01-01

    After dismantling of the titanium neutralizer plates inspection yielded satisfactory status of flat areas whereas edges and curved shapes were heavily melted. At the inner plates of the lower divertor strongly focused melting and cutting was found which is caused by fast electrons. These electrons are continuously produced. The production mechanism is not yet clear but runaway processes can be excluded. With long-pulse additional heating of 6 MW/10s as planned for ASDEX in 1987, the total energy delivered to the plasma will increase by a factor of 30. Therefore new water-cooled neutralizer plates have been constructed which consist of a copper-steel compound. The construction principle and the topology of the cooling circuits is presented

  20. Performance Evaluation of a Nanofluid-Based Direct Absorption Solar Collector with Parabolic Trough Concentrator

    Directory of Open Access Journals (Sweden)

    Guoying Xu

    2015-12-01

    Full Text Available Application of solar collectors for hot water supply, space heating, and cooling plays a significant role in reducing building energy consumption. For conventional solar collectors, solar radiation is absorbed by spectral selective coating on the collectors’ tube/plate wall. The poor durability of the coating can lead to an increased manufacturing cost and unreliability for a solar collector operated at a higher temperature. Therefore, a novel nanofluid-based direct absorption solar collector (NDASC employing uncoated collector tubes has been proposed, and its operating characteristics for medium-temperature solar collection were theoretically and experimentally studied in this paper. CuO/oil nanofluid was prepared and used as working fluid of the NDASC. The heat-transfer mechanism of the NDASC with parabolic trough concentrator was theoretically evaluated and compared with a conventional indirect absorption solar collector (IASC. The theoretical analysis results suggested that the fluid’s temperature distribution in the NDASC was much more uniform than that in the IASC, and an enhanced collection efficiency could be achieved for the NDASC operated within a preferred working temperature range. To demonstrate the feasibility of the proposed NDASC, experimental performances of an NDASC and an IASC with the same parabolic trough concentrator were furthermore evaluated and comparatively discussed.

  1. Performance Evaluation of a Nanofluid-Based Direct Absorption Solar Collector with Parabolic Trough Concentrator

    Science.gov (United States)

    Xu, Guoying; Chen, Wei; Deng, Shiming; Zhang, Xiaosong; Zhao, Sainan

    2015-01-01

    Application of solar collectors for hot water supply, space heating, and cooling plays a significant role in reducing building energy consumption. For conventional solar collectors, solar radiation is absorbed by spectral selective coating on the collectors’ tube/plate wall. The poor durability of the coating can lead to an increased manufacturing cost and unreliability for a solar collector operated at a higher temperature. Therefore, a novel nanofluid-based direct absorption solar collector (NDASC) employing uncoated collector tubes has been proposed, and its operating characteristics for medium-temperature solar collection were theoretically and experimentally studied in this paper. CuO/oil nanofluid was prepared and used as working fluid of the NDASC. The heat-transfer mechanism of the NDASC with parabolic trough concentrator was theoretically evaluated and compared with a conventional indirect absorption solar collector (IASC). The theoretical analysis results suggested that the fluid’s temperature distribution in the NDASC was much more uniform than that in the IASC, and an enhanced collection efficiency could be achieved for the NDASC operated within a preferred working temperature range. To demonstrate the feasibility of the proposed NDASC, experimental performances of an NDASC and an IASC with the same parabolic trough concentrator were furthermore evaluated and comparatively discussed. PMID:28347112

  2. PV-hybrid and thermoelectric collectors

    Energy Technology Data Exchange (ETDEWEB)

    Rockendorf, G.; Sillmann, R. [Institut fuer Solarenergieforschung GmbH, Emmerthal (Germany); Podlowski, L.; Litzenburger, B. [SolarWerk GmbH, Teltow (Germany)

    1999-07-01

    Two different principles of thermoelectric cogeneration solar collectors have been realized and investigated. Concerning the first principle, the thermoelectric collector (TEC) delivers electricity indirectly by first producing heat and subsequently generating electricity by means of a thermoelectric generator. Concerning the second principle, the photovoltaic-hybrid collector (PVHC) uses photovoltaic cells, which are cooled by a liquid heat-transfer medium. The characteristics of both collector types are described. Simulation modules have been developed and implemented in TRNSYS 14.1 (1994), in order to simulate their behaviour in typical domestic hot-water systems. The discussion of the results shows that the electric output of the PV-hybrid collector is significantly higher than that of the thermoelectric collector. (author)

  3. Solar Hot Water Heater

    Science.gov (United States)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

  4. Microsecond Electrical Discharge in Water in Plate-to-Plate Configuration With Nitrogen Bubble Injection

    Czech Academy of Sciences Publication Activity Database

    Stelmashuk, Vitaliy

    2016-01-01

    Roč. 44, č. 4 (2016), s. 702-707 ISSN 0093-3813 Institutional support: RVO:61389021 Keywords : Electric breakdown * plate electrodes * underwater discharge Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.052, year: 2016 http://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=7450213

  5. Inactivation of Heterosigma akashiwo in ballast water by circular orifice plate-generated hydrodynamic cavitation.

    Science.gov (United States)

    Feng, Daolun; Zhao, Jie; Liu, Tian

    2016-01-01

    The discharge of alien ballast water is a well-known, major reason for marine species invasion. Here, circular orifice plate-generated hydrodynamic cavitation was used to inactivate Heterosigma akashiwo in ballast water. In comparison with single- and multihole orifice plates, the conical-hole orifice plate yielded the highest inactivation percentage, 51.12%, and consumed only 6.84% energy (based on a 50% inactivation percentage). Repeating treatment, either using double series-connection or circling inactivation, elevated the inactivation percentage, yet consumed much more energy. The results indicate that conical-hole-generated hydrodynamic cavitation shows great potential as a pre-inactivation method for ballast water treatment.

  6. Garbage collector interface

    OpenAIRE

    Ive, Anders; Blomdell, Anders; Ekman, Torbjörn; Henriksson, Roger; Nilsson, Anders; Nilsson, Klas; Robertz, Sven

    2002-01-01

    The purpose of the presented garbage collector interface is to provide a universal interface for many different implementations of garbage collectors. This is to simplify the integration and exchange of garbage collectors, but also to support incremental, non-conservative, and thread safe implementations. Due to the complexity of the interface, it is aimed at code generators and preprocessors. Experiences from ongoing implementations indicate that the garbage collector interface successfully ...

  7. Countercurrent air/water and steam/water flow above a perforated plate. Report for October 1978-October 1979

    International Nuclear Information System (INIS)

    Hsieh, C.; Bankoff, S.G.; Tankin, R.S.; Yuen, M.C.

    1980-11-01

    The perforated plate weeping phenomena have been studied in both air/water and steam/cold water systems. The air/water experiment is designed to investigate the effect of geometric factors of the perforated plate on the rate of weeping. A new dimensionless flow rate in the form of H star is suggested. The data obtained are successfully correlated by this H star scaling in the conventional flooding equation. The steam/cold water experiment is concentrated on locating the boundary between weeping and no weeping. The effects of water subcooling, water inlet flow rate, and position of water spray are investigated. Depending on the combination of these factors, several types of weeping were observed. The data obtained at high water spray position can be related to the air/water flooding correlation by replacing the stream flow rate to an effective stream flow rate, which is determined by the mixing efficiency above the plate

  8. Evaluation of the solar water disinfection process (SODIS) against Cryptosporidium parvum using a 25-L static solar reactor fitted with a compound parabolic collector (CPC).

    Science.gov (United States)

    Fontán-Sainz, María; Gómez-Couso, Hipólito; Fernández-Ibáñez, Pilar; Ares-Mazás, Elvira

    2012-02-01

    Water samples of 0, 5, and 30 nephelometric turbidity units (NTU) spiked with Cryptosporidium parvum oocysts were exposed to natural sunlight using a 25-L static solar reactor fitted with a compound parabolic collector (CPC). The global oocyst viability was calculated by the evaluation of the inclusion/exclusion of the fluorogenic vital dye propidium iodide and the spontaneous excystation. After an exposure time of 8 hours, the global oocyst viabilities were 21.8 ± 3.1%, 31.3 ± 12.9%, and 45.0 ± 10.0% for turbidity levels of 0, 5, and 30 NTU, respectively, and these values were significantly lower (P 10 times).

  9. Presence and absence of a water film between moving air bubbles and a plate

    International Nuclear Information System (INIS)

    Remenyik, C.J.

    1990-01-01

    The thickness of water films between an inclined Lucite plate submerged in water and air bubbles moving beneath it was measured with a small impedance probe. The instrument was calibrated with a laser interferometer built for this purpose. The bubbles released beneath the plate varied in size from 10 cc to 100 cc. At a plate inclination angle of 0.98 degree, and in tap water, an uninterrupted water film covered most of the bubbles. Some bubbles, however, dewetted the plate, and the water film covered only a forward part of the bubble. When the film was uninterrupted, its thickness was very uniform from front to rear. When the bubble dewetted the plate, a large forward section of the film had the same uniform thickness, but this was followed by a hump on the film the rear slope of which ended at the plate surface. For some of the experiments, the surface tension of the water was reduced by admixing a detergent. In these experiments, dewetting was not observed. In a second set of experiments, a hand held transparent container filled with water and a 1.3 cm3 air bubble was used to observe visually the behavior of the moving bubble and its associated water film

  10. Experimental and theoretical evaluation of the performance of a tar solar water heater

    International Nuclear Information System (INIS)

    Ammari, H.D.; Nimir, Y.L.

    2003-01-01

    The paper presents an experimental and theoretical evaluation of the performance of a tar solar water heater and comparison with that of a conventional type collector. The performance of both collectors is assessed under the same conditions. Both of the collectors have the same surface area and are glazed. The conventional type has the water tubes welded to the absorber plate, whereas in the tar type, the tar acts as an absorber plate that covers the water tubes. The theoretical model for each collector type, with the transient effects taken into account, is based on a control volume and a time base in the related energy equations. By considering a small element of the collector in each case, three partial differential equations were developed for each collector and were solved numerically by the Runge-Kutta method of the fifth order. A good agreement was achieved between the numerical and experimental results for both the conventional and tar collectors, indicating the feasibility of employing the theoretical model in the design of flat plate solar collectors. The results also showed that the conventional collector is more efficient than the tar type during most of the daylight, but the tar collector had the added advantage of better conservation of energy in late afternoon and evening

  11. Caramel, uranium oxide fuel plates for water cooled reactors

    International Nuclear Information System (INIS)

    Bussy, Pierre; Delafosse, Jacques; Lestiboudois, Guy; Cerles, J.-M.; Schwartz, J.-P.

    1979-01-01

    The fuel is composed of thin plates assembled parallel to each other to form bundles or assemblies. Each plate is composed of a pavement of uranium oxide pellets, insulated from each other by a zircaloy cladding. The 235 U enrichment does not exceed 8%. The range of uses for this fuel extends from electric power generating reactors to irradiation reactors for research work. A parametric study in test loops has made it possible to determine the operating limits of this thick fuel, without bursting. The resulting diagram gives the permissible power densities, with and without cycling for specific burn-ups beyond 50,000 MWd/t. The thinnest plates were also irradiated in total in the form of advance assemblies irradiated in the core of the OSIRIS pile prior to its transformation. This transformation and the operation of this reactor with a core of 'Caramel' elements is the main trial experiment of this fuel [fr

  12. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  13. Photovoltaic-thermal (PV/T) solar collectors: Features and performance modelling

    International Nuclear Information System (INIS)

    Atienza-Márquez, Antonio; Bruno, Joan Carles; Coronas, Alberto; Korolija, Ivan; Greenough, Richard; Wright, Andy

    2017-01-01

    Currently, the electrical efficiency of photovoltaic (PV) solar cells ranges between 5–25%. One of the most important parameters that affects the electrical efficiency of a PV collector is the temperature of its cells: the higher temperature, the lower is the efficiency. Photovoltaic/thermal (PV/T) technology is a potential solution to ensure an acceptable solar energy conversion. The PV/T technology produces both electrical and thermal energy simultaneously. It is suitable for low temperature applications (25–40 o C) and overall efficiency increases compared to individual collectors. This paper describes an installation in a single-family house where PV/T collectors are coupled with a ground heat exchanger and a heat pump for domestic hot water and space heating purposes. The aim of this work is twofold. First, the features of the PV/T technology are analyzed. Second, a model of a flat-plate PV/T water collector was developed in TRNSYS in order to analyze collectors performance. (author)

  14. Dynamic testing of solar collectors under special consideration of the correction of the inclination angle and reduction of the test duration; Dynamische Pruefung von Sonnenkollektoren unter besonderer Beruecksichtigung der Einfallswinkelkorrektur und der Reduzierung der Pruefdauer

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Stephan

    2011-07-01

    Solar thermal systems are gaining more and more market shares. At the beginning of the last decade only systems for swimming pool heating and domestic hot water heating were available on the market. Today the system variety includes additionally solar thermal systems for space heating, solar thermal cooling, process heat and solar thermal power plants. Independent of the purpose of the solar thermal system, it is always the collector that converts the solar irradiance into heat and is thus the most important component within a solar thermal system. The high number of applications results also in a large variety of different collector concepts. The differences between flat plate collectors, evacuated tubular collectors (with or without heat pipes). CPC collectors, parabolic trough collectors. Fresnel collectors and others is not limited to geometry and working principles but include as well the thermal performance, especially when the thermal behaviour under different angles of incidence and fractions of diffuse irradiance is taking into account. For the test of solar thermal collectors and for the optimisation of solar thermal systems a mathematical model is necessary to describe the thermal performance of the solar collector. Thus this thesis is dealing with the mathematic modelling and the experimental testing of solar thermal collectors. Based on already existing procedures a numerical model and a new procedure for the test of thermal collectors is introduced. The numerical model enables the description of the thermal behaviour for most collectors available on the market. The numerical model and the test procedure were developed paying special attention to the incidence angle modifier and the reduction of testing time. As basis for the general numerical model and the test procedure part one of the thesis describes and discusses the parameters needed to characterise the thermal performance of solar thermal collectors. It is shown that some of the influencing

  15. Performance analysis of a minichannel-based solar collector using different nanofluids

    International Nuclear Information System (INIS)

    Mahian, Omid; Kianifar, Ali; Sahin, Ahmet Z.; Wongwises, Somchai

    2014-01-01

    Highlights: • Performance of a minichannel-based solar collector has been studied using four different nanofluids. • First and second law thermodynamic analyses are conducted by considering constant mass flow rate of nanofluid. • Al 2 O 3 /water nanofluids show the highest heat transfer coefficient in the tubes. • The highest outlet temperature is provided by Cu/water nanofluids. • Cu/water nanofluid produces the lowest entropy generation among the nanofluids. - Abstract: In this paper, an analytical analysis has been performed to evaluate the performance of a minichannel-based solar collector using four different nanofluids including Cu/water, Al 2 O 3 /water, TiO 2 /water, and SiO 2 /water. The analysis of first and second laws is conducted for turbulent flow by considering the constant mass flow rate of nanofluid. The results are presented for volume fractions up to 4% and nanoparticle size of 25 nm where the inner diameter of the risers of flat plate collector is assumed to be 2 mm. Analysis of the first law of thermodynamics reveals that Al 2 O 3 /water nanofluids show the highest heat transfer coefficient in the tubes while the lowest value belongs to SiO 2 /water nanofluids. The highest outlet temperature is provided by Cu/water nanofluids, and after that TiO 2 /water, Al 2 O 3 /water, and SiO 2 /water nanofluids are in ranks of second to fourth. The results of second law analysis elucidate that Cu/water nanofluid produces the lowest entropy generation among the nanofluids. It is found that although the effective thermal conductivity of TiO 2 /water nanofluids is less than Al 2 O 3 /water nanofluids, but the entropy generation of TiO 2 /water is lower than Al 2 O 3 /water. Finally, some recommendations are given for future studies on the applications of nanofluids in solar collectors

  16. Modular Porous Plate Sublimator /MPPS/ requires only water supply for coolant

    Science.gov (United States)

    Rathbun, R. J.

    1966-01-01

    Modular porous plate sublimators, provided for each location where heat must be dissipated, conserve the battery power of a space vehicle by eliminating the coolant pump. The sublimator requires only a water supply for coolant.

  17. Recent progress in terrestrial photovoltaic collector technology

    Science.gov (United States)

    Ferber, R. R.

    1982-01-01

    The U.S. Photovoltaic Research and Development Program has the objective to develop the technology necessary to foster widespread grid-competitive electric power generation by the late 1980s. The flat-plate and the concentrator collector activities form the nucleus of the program. The project is concerned with the refining of silicon, silicon sheet production, solar cell processing and fabrication, encapsulation materials development, and collector design and production. The Large-Area Silicon Sheet Task has the objective to develop and demonstrate the feasibility of several methods for producing large area silicon sheet material suitable for fabricating low-cost, high-efficiency solar cells. It is expected that a variety of economic flat-plate and concentrator collectors will become commercially available for grid-connected applications.

  18. Collector sealants and breathing. Final Report, 25 September 1978-31 December 1979

    Energy Technology Data Exchange (ETDEWEB)

    Mendelsohn, M A; Luck, R M; Yeoman, F A; Navish, Jr, F W

    1980-02-20

    The objectives of this program were: (1) to investigate the pertinent properties of a variety of possible sealants for solar collectors and identify the most promising candidates, and (2) to study the effect of breathing in flat-plate, thermal solar collector units. The study involved two types of sealants, Class PS which includes preformed seals or gaskets and Class SC which includes sealing compounds or caulks. It was the intent of the study to obtain data regarding initial properties of candidate elastomers from manufacturers and from the technical literature and to use those sources to provide data pertaining to endurance of these materials under environmental service conditions. Where necessary, these data were augmented by experimental measurements. Environmental stresses evaluated by these measurements included elevated temperatures, moisture, ultraviolet light, ozone and oxygen, and fungus. The second major area of the work involved a study of the effects of materials used and design on the durability of solar collectors. Factors such as design, fabrication, materials of construction, seals and sealing techniques and absorber plate coatings were observed on actual field units removed from service. Such phenomena as leakage, corrosion and formation of deposits on glazing and absorber plate were noted. An evaluation of the properties of several desiccants was made in order to providemeans to mitigate the deleterious effects of water on collector life. Adsorbents for organic degradation products of sealants were also investigated in order to protect the glazing and absorber plate from deposited coatings. Since adsorbents and desiccants in general tend to take up both water and organic decomposition products, relative affinities of a number of these agents for water and for organic compounds were determined . Results are presented in detail.

  19. Performance of an absorbing concentrating solar collectors

    International Nuclear Information System (INIS)

    Imadojemu, H.

    1990-01-01

    This paper reports on a comparison of the efficiency of an absorbing fluid parabolic trough concentrating solar collector and a traditional concentrating collector that was made. In the absorbing fluid collector, black liquid flows through a glass tube absorber while the same black liquid flows through a selective black coated copper tube absorber while the same black fluid flows through a selective black coated copper tube absorber in the traditional collector. After a careful study of the properties of available black liquids, a mixture of water and black ink was chosen as the black absorbing medium or transfer fluid. In the black liquid glass collector there is a slightly improved efficiency based on beam radiation as a result of the direct absorption process and an increase in the effective transmittance absorptance. At worst the efficiency of this collector equals that of the traditional concentrating collector when the efficiency is based on total radiation. The collector's reflecting surfaces were made of aluminum sheet, parabolic line focus and with cylindrical receivers. The ease of manufacture and reduced cost per unit energy collected, in addition to the clean and pollution free mode of energy conversion, makes it very attractive

  20. Simultaneous separation of copper, cadmium and cobalt from sea-water by co-flotation with octadecylamine and ferric hydroxide as collectors.

    Science.gov (United States)

    Cabezon, L M; Caballero, M; Cela, R; Perez-Bustamante, J A

    1984-08-01

    A method is proposed for the simultaneous quantitative separation of traces ofCu(II), Cd(II) and Co(II) from sea-water samples by means of the co-flotation (adsorbing colloid flotation) technique with ferric hydroxide as co-precipitant and octadecylamine as collector. The experimental parameters have been studied and optimized. The drawbacks arising from the low solubility of octadecylamine and the corresponding sublates in water have been avoided by use of a 6M hydrochloric acid-MIBK-ethanol (1:2:2 v v ) mixture. The results obtained by means of the proposed method have been compared with those given by the usual ammonium pyrrolidine dithiocarbamate/MIBK extraction method.

  1. Design of a Solar Water Heating System for Kuti Hall, University of ...

    African Journals Online (AJOL)

    Monthly average daily irradiance in plane of solar collector and Cold water temperature calculated from weather data collated to determine heating load. Mathematical model was developed based on heat transfer, thermal and optical and energy performance of collector. The absorber plate area, dimensions of solar ...

  2. Performance of solar collectors under low temperature conditions

    DEFF Research Database (Denmark)

    Bunea, Mircea; Eicher, Sara; Hildbrand, Catherine

    The performance of four solar thermal collectors (flat plate, evacuated tube, unglazed with rear insulation and unglazed without rear insulation) was experimentally measured and simulated for temperatures below ambient. The influence of several parameters (e.g. collector inlet temperature, air...... evaluated and results compared to experimental measurements. A mathematical model is also under development to include, in addition to the condensation phenomena, the frost, the rain and the long-wave radiation gains/losses on the rear of the solar collector. While the potential gain from rain was estimated...... to be around 2%, frost heat gains were measured to be up to 40% per day, under specific conditions. Overall, results have shown that unglazed collectors are more efficient than flat plate or evacuated tube collectors at low operation temperatures or for night conditions, making them more suitable for heat pump...

  3. Development of 12.5 m² Solar Collector Panel for Solar Heating Plants

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian; Furbo, Simon; Shah, Louise Jivan

    2004-01-01

    and large solar heating systems. Based on the theoretical findings a prototype of an improved HT solar collector was built and tested side-by-side with the original HT solar collector. The improved HT collector makes use of a changed insulation material, an absorber with improved absorptance and emittance......Theoretical and experimental investigations have elucidated how different changes in the design of the 12.5 m(2) HT flat-plate solar collector from the Danish company ARCON Solvarme A/S influence the solar collector efficiency and the yearly thermal performance. The collector is designed for medium...

  4. Radiation energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Bei Tse; Rabl, A

    1977-02-10

    The invention deals with a concentrating solar collector. Collectors of this kind often have considerable natural convection losses which are due, among other facts, to the location of the energy absorber at the outlet with the heated surface of the absorber facing the inlet opening of the collector. According to the invention, the collector is designed in such manner that the absorber is located inside a space in such a way that the radiation emitted by the absorber is reflected back to the absorber with the aid of mirror surfaces. Various designs are described.

  5. Thermal Modeling of a Hybrid Thermoelectric Solar Collector with a Compound Parabolic Concentrator

    Science.gov (United States)

    Lertsatitthanakorn, C.; Jamradloedluk, J.; Rungsiyopas, M.

    2013-07-01

    In this study radiant light from the sun is used by a hybrid thermoelectric (TE) solar collector and a compound parabolic concentrator (CPC) to generate electricity and thermal energy. The hybrid TE solar collector system described in this report is composed of transparent glass, an air gap, an absorber plate, TE modules, a heat sink to cool the water, and a storage tank. Incident solar radiation falls on the CPC, which directs and reflects the radiation to heat up the absorber plate, creating a temperature difference across the TE modules. The water, which absorbs heat from the hot TE modules, flows through the heat sink to release its heat. The results show that the electrical power output and the conversion efficiency depend on the temperature difference between the hot and cold sides of the TE modules. A maximum power output of 1.03 W and a conversion efficiency of 0.6% were obtained when the temperature difference was 12°C. The thermal efficiency increased as the water flow rate increased. The maximum thermal efficiency achieved was 43.3%, corresponding to a water flow rate of 0.24 kg/s. These experimental results verify that using a TE solar collector with a CPC to produce both electrical power and thermal energy seems to be feasible. The thermal model and calculation method can be applied for performance prediction.

  6. Water in geodynamical models of mantle convection and plate tectonics

    Science.gov (United States)

    Rodríguez-González, J.; Van Hunen, J.; Chotalia, K.; Lithgow-Bertelloni, C. R.; Rozel, A.; Tackley, P. J.; Nakagawa, T.

    2017-12-01

    The presence of water in the the mantle has a significant effect in the dynamical and thermal evolution of Earth, which partially explains the differences with other planets and is a key factor for the presence of life on Earth. First, a small amount of water can decrease the mantle viscosity by a several orders of magnitude, thereby changing the convection regime and affecting the thermal evolution. Second, the presence of water significantly changes the solidus curve, with crucial implications for melting. Third, water in the mantle can change the Clapeyron slope of mantle materials, which changes the depth at which phase transitions take place. The thermal and dynamical evolution of Earth under the presence of water in the mantle has been the focus of recent studies, but many questions remain unanswered. In this project we intend to investigate how the maximum water capacity of different mantle regions affects water transport and Earth's convective regime. We will study the effect phase transitions under the presence of water, which can change the buoyancy of slabs in the transition zone. We present preliminary results numerical models of global mantle convection for the whole history of earth using the numerical geodynamics software tool StagYY. We will use a new parametrisation of dehydration processes, obtained from high-resolution numerical simulations, to implement a more accurate description of the water released from the slab as it travels through the mantle. We have integrated recent experimental results of the water capacity of deep mantle minerals to study the water circulation and the total water budget. We use data from the most recent experiments and ab-inito calculations to implement a realistic rheology.

  7. The numerical simulation of the performances of water rotors used in pipelines with the water baffle plates

    Energy Technology Data Exchange (ETDEWEB)

    Altan, Burcin Deda [Pamukkale University, Kinikli (Turkmenistan)

    2014-11-15

    In this study, obtaining energy especially from large and medium sized pipelines used for drinking water, rain water, or even some used for waste water has been aimed. In line with this objective, it has been investigated how to increase the performance of the water rotors used in the pipelines in order to benefit optimally from the energy of the flowing fluid in pipe. Furthermore, in order to increase the performance of the water rotor used in pipelines, a water baffle plate has been placed in front of the water rotor. In this way, the effects of size parameters of the water rotor used in the pipeline in conjunction with the various design parameters of the water baffle plate on the power performance of rotor has been investigated. By comparing design parameters, the number of the water rotor blades has also been investigated. Optimization steps have been carried out with numerical results of the study supported by theoretical computation. For numerical optimization of the water rotor, both static and dynamic performances of rotor have been found. According to the optimization study, the maximum power performance values have been obtained from a power pipe unit which consists of a water rotor and a water baffle plate with (x{sub g} /r{sub r} = 0.1, y{sub g}/r{sub r} = 0.4, ve r{sub r}/r{sub p} = 0.4 ve α = 60 .deg. ) size ratios.

  8. The numerical simulation of the performances of water rotors used in pipelines with the water baffle plates

    International Nuclear Information System (INIS)

    Altan, Burcin Deda

    2014-01-01

    In this study, obtaining energy especially from large and medium sized pipelines used for drinking water, rain water, or even some used for waste water has been aimed. In line with this objective, it has been investigated how to increase the performance of the water rotors used in the pipelines in order to benefit optimally from the energy of the flowing fluid in pipe. Furthermore, in order to increase the performance of the water rotor used in pipelines, a water baffle plate has been placed in front of the water rotor. In this way, the effects of size parameters of the water rotor used in the pipeline in conjunction with the various design parameters of the water baffle plate on the power performance of rotor has been investigated. By comparing design parameters, the number of the water rotor blades has also been investigated. Optimization steps have been carried out with numerical results of the study supported by theoretical computation. For numerical optimization of the water rotor, both static and dynamic performances of rotor have been found. According to the optimization study, the maximum power performance values have been obtained from a power pipe unit which consists of a water rotor and a water baffle plate with (x g /r r = 0.1, y g /r r = 0.4, ve r r /r p = 0.4 ve α = 60 .deg. ) size ratios.

  9. Short-Term Solar Collector Power Forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Perers, Bengt

    2011-01-01

    This paper describes a new approach to online forecasting of power output from solar thermal collectors. The method is suited for online forecasting in many applications and in this paper it is applied to predict hourly values of power from a standard single glazed large area flat plate collector...... enabling tracking of changes in the system and in the surrounding conditions, such as decreasing performance due to wear and dirt, and seasonal changes such as leaves on trees. This furthermore facilitates remote monitoring and check of the system....

  10. Influence of material anisotropy on the hydroelastic response of composite plates in water

    Science.gov (United States)

    Akcabay, Deniz Tolga; Young, Yin Lu

    2018-03-01

    Flexible lightweight plate-like lifting surfaces in external flows have a diverse range of use from propelling and controlling marine and aerospace vehicles to converting wind and ocean energy to electrical energy. Design and analysis of such structures are complex for underwater applications where the water density is much higher than air. The hydrodynamic loads, which vary with the inflow speed, can significantly alter the dynamic response and stability. This paper focuses on the hydroelastic response of composite plates in water. The results show that the dynamics and stability of the structure can be significantly modified by taking advantage of the material anisotropic; on the contrary, careless composite material designs may lead to unwanted dynamic instability failures. The resonance frequencies, divergence speeds, and fluid loss coefficients change with material anisotropy and hydrodynamic loads. The resonance frequencies are much lower in water than in air. The critical divergence speed increases, if the principal fiber direction is oriented towards the inflow. Hydrodynamic damping is shown to be much higher than the material damping, and tend to increase with flow speed and to decrease with increasing modal frequency. The paper derives Response Amplitude Operators (RAOs) for sample composite plates in water and use them to predict the motion response when subject to stochastic flow excitations. We show how material anisotropy can be used to passively tailor the plate vibration response spectrum to limit or enhance flow-induced vibrations of the plate depending on the desired applications.

  11. Experimental observations and modelling of thermal history within a steel plate during water jet impingement

    International Nuclear Information System (INIS)

    Liu, Z.D.; Fraser, D.; Samarasekera, I.V.; Lockhart, G.T.

    2002-01-01

    In order to investigate heat transfer of steel plates under a water jet impingement and to further simulate runout table operation in a hot strip mill, a full-scale pilot runout table facility was designed and constructed at the University of British Columbia (UBC). This paper describes the experimental details, data acquisition and data handling techniques for steel plates during water jet impingement by one circular water jet from an industrial header. Recorded visual observations at the impinging surface were obtained. The effects of cooling water temperature and impingement velocity on the heat transfer from a steel plate were studied. A two-dimensional finite element method-based transient inverse heat conduction model was developed. With the help of the model, heat fluxes and heat transfer coefficients along the impinging surface under various cooling conditions were calculated. The microstructural evolution of the steel plate was also investigated for the varying cooling conditions. Samples were obtained from each plate, polished, etched and then photographed. (author)

  12. Solar collector overheating protection

    NARCIS (Netherlands)

    Slaman, M.J.; Griessen, R.P.

    Prismatic structures in a thermal solar collector are used as overheating protection. Such structures reflect incoming light efficiently back whenever less thermal power is extracted from the solar collector. Maximum thermal power is generated when the prismatic structure is surrounded by a

  13. Corrosion Behavior of Nickel-Plated Alloy 600 in High Temperature Water

    International Nuclear Information System (INIS)

    Kim, Ji Hyun; Hwang, Il Soon

    2008-01-01

    In this paper, electrochemical and microstructural characteristics of nickel-plated Alloy 600 wee investigated in order to identify the performance of electroless Ni-plating on Alloy 600 in high-temperature aqueous condition with the comparison of electrolytic nickel-plating. For high temperature corrosion test of nickel-plated Alloy 600, specimens were exposed for 770 hours to typical PWR primary water condition. During the test, open circuit potentials (OCP's) of all specimens were measured using a reference electrode. Also, resistance to flow accelerated corrosion (FAC) test was examined in order to check the durability of plated layers in high-velocity flow environment at high temperature. After exposures to high flow rate aqueous condition, the integrity of surfaces was confirmed by using both scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). For the field application, a remote process for electroless nickel-plating was demonstrated using a plate specimen with narrow gap on a laboratory scale. Finally, a practical seal design was suggested for more convenient application

  14. Temperature dependence of the evaporation lengthscale for water confined between two hydrophobic plates.

    Science.gov (United States)

    Djikaev, Yuri S; Ruckenstein, Eli

    2015-07-01

    Liquid water in a hydrophobic confinement is the object of high interest in physicochemical sciences. Confined between two macroscopic hydrophobic surfaces, liquid water transforms into vapor if the distance between surfaces is smaller than a critical separation, referred to as the evaporation lengthscale. To investigate the temperature dependence of the evaporation lengthscale of water confined between two hydrophobic parallel plates, we use the combination of the density functional theory (DFT) with the probabilistic hydrogen bond (PHB) model for water-water hydrogen bonding. The PHB model provides an analytic expression for the average number of hydrogen bonds per water molecule as a function of its distance to a hydrophobic surface and its curvature. Knowing this expression, one can implement the effect of hydrogen bonding between water molecules on their interaction with the hydrophobe into DFT, which is then employed to determine the distribution of water molecules between two macroscopic hydrophobic plates at various interplate distances and various temperatures. For water confined between hydrophobic plates, our results suggest the evaporation lengthscale to be of the order of several nanometers and a linearly increasing function of temperature from T=293 K to T=333 K, qualitatively consistent with previous results. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Thermal performances of vertical hybrid PV/T air collector

    Science.gov (United States)

    Tabet, I.; Touafek, K.; Bellel, N.; Khelifa, A.

    2016-11-01

    In this work, numerical analyses and the experimental validation of the thermal behavior of a vertical photovoltaic thermal air collector are investigated. The thermal model is developed using the energy balance equations of the PV/T air collector. Experimental tests are conducted to validate our mathematical model. The tests are performed in the southern Algerian region (Ghardaïa) under clear sky conditions. The prototype of the PV/T air collector is vertically erected and south oriented. The absorber upper plate temperature, glass cover temperature, air temperature in the inlet and outlet of the collector, ambient temperature, wind speed, and solar radiation are measured. The efficiency of the collector increases with increase in mass flow of air, but the increase in mass flow of air reduces the temperature of the system. The increase in efficiency of the PV/T air collector is due to the increase in the number of fins added. In the experiments, the air temperature difference between the inlet and the outlet of the PV/T air collector reaches 10 ° C on November 21, 2014, the interval time is between 10:00 and 14:00, and the temperature of the upper plate reaches 45 ° C at noon. The mathematical model describing the dynamic behavior of the typical PV/T air collector is evaluated by calculating the root mean square error and mean absolute percentage error. A good agreement between the experiment and the simulation results is obtained.

  16. Financial viability study using a heat pump as an alternative to support solar collector for water heating in Southeastern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Roberts Vinicius de Melo; Oliveira, Raphael Nunes; Machado, Luiz; Koury, Ricardo Nassau N. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. of Mechanical Engineering], E-mails: robertsreis@ufmg.br, luizm@demec.ufmg.br, koury@ufmg.br

    2010-07-01

    Along with related greenhouse effect environmental issues, constant problems changes in oil prices,make the use of solar energy an important renewable energy source. Brazil is a country which is privilege, considering the high rates of solar irradiation present throughout most of the entire national territory. Nevertheless, during certain times of the year, a solar energy deficit, leads solar systems to require electrical resistance support. The use of electrical resistance represents 23.5% of electric energy consumption and it presents a low residential energy efficiency. The purpose of this work is conducting a study of Brazilian States in the Southeastern region regarding the financial viability of replacing a resistive system combined with the use of solar collector and a heat pump. One such heat pump has been designed, constructed and tested experimentally. The average performance coefficient is equal to 2.10, a low value due to the use of a hermetic reciprocating compressor. Despite this low-moderate price coefficient of acquisition and installation of a heat pump, a return on investment in from 2.1 to 2.7 years can be expected. Whereas the equipment has a useful life of about 20 years, this period of return on investment is interesting. (author)

  17. Low velocity impact on polymer composite plates in contact with water

    Directory of Open Access Journals (Sweden)

    Y Kwon

    2016-09-01

    Full Text Available In this study, composite materials were tested in two different environments to determine the role of Fluid Structure Interaction with composites under a low velocity impact. This was done using a low velocity impact machine and polymer composite plates. The composite is made of laminated symmetrical plain weave E-glass fabrics. The test area of the composite plates is 30.5 cm by 30.5 cm with clamped boundary conditions. The testing was done using a drop weight system to impact the center of the test area. One testing was performed with composite plates in air, called dry impact. The other testing was conducted while composite plates were submerged in water, called wet impact. A Plexiglas box in conjunction with the impact machine was used to keep the top of the composite sample dry while it was submerged in an anechoic water tank, so called water-backed air impact. Output from the tests was recorded using strain gauges and a force impact sensor. The results show that an added mass effect from the water plays a large role in the Fluid Structure Interaction with composites due to the similar densities of water and the composites. The wet impact results in a larger impact force and damage than the dry impact under the same impact condition, i.e., the same impact mass and drop height.

  18. Dynamically slow processes in supercooled water confined between hydrophobic plates

    Energy Technology Data Exchange (ETDEWEB)

    Franzese, Giancarlo [Departamento de Fisica Fundamental, Universidad de Barcelona, Diagonal 647, Barcelona 08028 (Spain); Santos, Francisco de los, E-mail: gfranzese@ub.ed, E-mail: fdlsant@ugr.e [Departamento de Electromagnetismo y Fisica de la Materia, Universidad de Granada, Fuentenueva s/n, 18071 Granada (Spain)

    2009-12-16

    We study the dynamics of water confined between hydrophobic flat surfaces at low temperature. At different pressures, we observe different behaviors that we understand in terms of the hydrogen bond dynamics. At high pressure, the formation of the open structure of the hydrogen bond network is inhibited and the surfaces can be rapidly dried (dewetted) by formation of a large cavity with decreasing temperature. At lower pressure we observe strong non-exponential behavior of the correlation function, but with no strong increase of the correlation time. This behavior can be associated, on the one hand, to the rapid ordering of the hydrogen bonds that generates heterogeneities and, on the other hand, to the lack of a single timescale as a consequence of the cooperativity in the vicinity of the liquid-liquid critical point that characterizes the phase diagram at low temperature of the water model considered here. At very low pressures, the gradual formation of the hydrogen bond network is responsible for the large increase of the correlation time and, eventually, the dynamical arrest of the system, with a strikingly different dewetting process, characterized by the formation of many small cavities.

  19. Dynamically slow processes in supercooled water confined between hydrophobic plates

    International Nuclear Information System (INIS)

    Franzese, Giancarlo; Santos, Francisco de los

    2009-01-01

    We study the dynamics of water confined between hydrophobic flat surfaces at low temperature. At different pressures, we observe different behaviors that we understand in terms of the hydrogen bond dynamics. At high pressure, the formation of the open structure of the hydrogen bond network is inhibited and the surfaces can be rapidly dried (dewetted) by formation of a large cavity with decreasing temperature. At lower pressure we observe strong non-exponential behavior of the correlation function, but with no strong increase of the correlation time. This behavior can be associated, on the one hand, to the rapid ordering of the hydrogen bonds that generates heterogeneities and, on the other hand, to the lack of a single timescale as a consequence of the cooperativity in the vicinity of the liquid-liquid critical point that characterizes the phase diagram at low temperature of the water model considered here. At very low pressures, the gradual formation of the hydrogen bond network is responsible for the large increase of the correlation time and, eventually, the dynamical arrest of the system, with a strikingly different dewetting process, characterized by the formation of many small cavities.

  20. The flow in an oil/water plate heat exchanger for the automotive industry

    OpenAIRE

    Lozano , A.; Barreras , F.; Fueyo , N.; Santodomingo , S.

    2008-01-01

    The flow in an oil/water plate heat exchanger for the automotive industry correspondence: Corresponding author. Tel.: +34976716463; fax: +34976716456. (Lozano, A.) (Lozano, A.) LITEC/CSIC--> , Mar?'a de Luna 10--> , 50018--> , Zaragoza--> - SPAIN (Lozano, A.) SPAIN (Lozano, A.) LITEC/CSIC--> , Mar?'a de Luna 10--> , 50018--> , Zaragoza--> - S...

  1. Production of monodispersed Oil-in Water Emulsion Using Crossflow-Type Silicon Microchannel Plate

    Energy Technology Data Exchange (ETDEWEB)

    Kawakatsu, Takahiro.; Komori, Hideaki.; Yonemoto, Toshikuni. [Tohoku University, Miyagi (Japan). Chemical Engineering Department; Nakajima, Mitsutoshi.; Kikuchi, Yuji. [National Food Research Institute, Ibaraki (Japan)

    1999-04-01

    A novel method for continuous productin of monodispersed oil-in-water (O/W) emulsion is developed using acrossflow-type silicaon microchannel plate. On the single crystal silicon plate, a liquid flow path for continuous phase was made, and at each side of th wall of the path an array of regular-sized slits was precisely fabricated. A flat glass plate was tightly attached on the microchannel plate to cover the top of the slits to form the array of microchannels. Regular-sized oil (triolein) droplets were generated by squeezing the oil through the microchannels into the continuous-phase water (0.3 wt% sodium lauryl sulfate solutin) flowing in the liquid path. Oil droplet size is significantly dependent on the microchannel structure, which is identified with the microchannel width, height, and the length of the terrace (a flat area at the microchannel outlet). Three types of microchannel plates having different microchannel structures generate monodispersed emulsions of different average droplet sizes, 16,20, and 48 {mu}m at the watr flow rate of 1.4x10{sup -2}mL{center_dot}min{sup -1}. For the microchannel plate which generates large droplets of 48 {mu}m, increasing the flow rate causes decreasing droplet size. However, for the microchannel plate which generates small droplets of 16 or 20 {mu}m, the size is not affected by the flow rate within the range from 1.4x10{sup -2}to 2.4 mL{center_dot}min{sup -1}. In every case, the droplet size distribution is narrow, and the geometric standard deviation is 1.03 or less. (author)

  2. Experimental studies of rectangular tube absorber photovoltaic thermal collector with various types of nanofluids under the tropical climate conditions

    International Nuclear Information System (INIS)

    Al-Shamani, Ali Najah; Sopian, K.; Mat, Sohif; Hasan, Husam Abdulrasool; Abed, Azher M.; Ruslan, M.H.

    2016-01-01

    Highlights: • A new rectangular tube as absorber for the PVT solar collector was developed. • Different types of nanofluids (SiO_2, TiO_2 and SiC) evaluated. • η_e_l PVT SiC nanofluid was 13.52% at 1000 W/m"2 and flow rate of 0.17 kg/s. • η_c_o_m_b_i_n_e_d PVT SiC nanofluid was 81.73% at 1000 W/m"2 and flow rate of 0.17 kg/s. - Abstract: The flat plate photovoltaic thermal (PVT) collectors can be classified into the type of working fluids used namely the water based PVT collectors, air based PVT collectors and combination of water/air PVT collectors. However, low thermal conductivity of the working fluids has always been the primary limitation in the development of energy-efficient heat transfer fluids, and higher collector performance. To overcome this limitation, there is a strong motivation to improve the heat transfer of fluids with higher thermal conductivity. This new generation of heat transfer fluids called nanofluids consists of suspended nanoparticles and has higher suspension stability compared to the millimeter or micrometer size nanoparticles. Thus, the heat transfer characteristics will be enhanced by using nanofluids. The PVT collector has been designed, fabricated and tested outdoor under the Malaysia tropical climate conditions. The PVT collector consists of specially designed rectangular tube absorber (stainless steel material, height of 15 mm, width of 25 mm and thickness of 1 mm) attached under the photovoltaic module. The PVT collector was experimentally tested with different types of nanofluids (SiO_2, TiO_2 and SiC). The results indicated that the PVT collector with SiC nanofluid has the highest combined photovoltaic thermal (PVT) efficiency of 81.73% and PVT electrical efficiency of 13.52% with the best overall energy coefficient (COE) of 0.93 has been achieved at a flow rate of 0.170 kg/s and solar irradiance levels of 1000 W/m"2, followed by PVT-TiO_2 nanofluids, PVT-SiO_2 nanofluids, and PVT-water respectively.

  3. Performance of non-conventional solar collectors in local market of Nawabshah

    International Nuclear Information System (INIS)

    Memon, M.; Tanwani, N.K.; Memon, A.H.

    1998-01-01

    This paper presents experimental studies concerning the performance of solar collectors using sand-bed as absorbing surface and a collector. These collectors were designed, manufactured locally and tested in meteorological conditions of Nawabshah, Sindh, Pakistan. The ordinary tap water was used as working fluid and tests were carried out in open space during day time. The effect of collector area and tubing diameter on collector performance was investigated. For each test run ambient, inlet and outlet water temperature together with flow rate of collector fluid was recorded. Two collectors connected in series showed an increase of about 20 deg. C in outlet temperature of water. Thus an average increase of 15 deg. C in the temperature was observed for each collector. The temperature was raised to 90 deg. C using the concentrator in combination with the two non-conventional flat collectors. (author)

  4. Variation in Lateral Plate Quality in Threespine Stickleback from Fresh, Brackish and Marine Water: A Micro-Computed Tomography Study.

    Directory of Open Access Journals (Sweden)

    Elisabeth Wiig

    Full Text Available It is important to understand the drivers leading to adaptive phenotypic diversity within and among species. The threespine stickleback (Gasterosteus aculeatus has become a model system for investigating the genetic and phenotypic responses during repeated colonization of fresh waters from the original marine habitat. During the freshwater colonization process there has been a recurrent and parallel reduction in the number of lateral bone plates, making it a suitable system for studying adaptability and parallel evolution.The aim of this study was to investigate an alternative evolutionary path of lateral plate reduction, where lateral plates are reduced in size rather than number.A total of 72 threespine stickleback individuals from freshwater (n = 54, brackish water (n = 27 and marine water (n = 9 were analysed using microcomputed tomography (μCT to determine variation in size, thickness and structure of the lateral plates. Furthermore, whole-body bone volume, and bone volume, bone surface and porosity of lateral plate number 4 were quantified in all specimens from each environment.The results showed a significant difference in plate size (area and volume among populations, where threespine stickleback from polymorphic freshwater and brackish water populations displayed lateral plates reduced in size (area and volume compared to marine stickleback.Reduction of lateral plates in threespine stickleback in fresh and brackish water occurs by both plate loss and reduction in plate size (area and volume.

  5. PERFORMANCE DETERIORATION OF THERMOSIPHON SOLAR FLAT PLATE WATER HEATER DUE TO SCALING

    OpenAIRE

    arunachala umesh chandavar

    2011-01-01

    The performance of Flat plate Solar Water Heater deteriorates within five to twelve years of their installation due to factors related to manufacturing, operating conditions, lack of maintenance etc. Especially, problem due to scaling is significant as it is based on quality of water used. The remaining factors are system dependent and could be overcome by quality production. Software is developed by incorporating Hottel Whillier Bliss (H-W-B) equation to ascertain the effect of scaling o...

  6. Natural convection in a water tank with a heated horizontal plate facing downward

    International Nuclear Information System (INIS)

    Yang, Sun Kyoo; Jung, Moon Kee; Helmut Hoffmann

    1995-01-01

    Experimental and computational studies were carried out to investigate the natural convection of the single phase flow in a tank with a heated horizontal plate facing downward. This is a simplified model for investigations of the influence of a core melt at the bottom of a reactor vessel on the thermal hydraulic behavior in a water filled cavity surrounding the vessel. In this case the vessel is simulated by a hexahedron insulated box with a heated plate horizontally mounted at the bottom of the box. The box with the heated plate is installed in a water filled hexahedron tank. Coolers are immersed in the U-type water volume between the box and the tank. Although the multicomponent flows exist more probably below the heated plate in reality, present study concentrates on the single phase flow in a first step prior to investigating the complicated multicomponent thermal hydraulic phenomena. In the present study, in order to get a better understanding for the natural convection characteristics below the heated plate, the velocity and temperature are measured by LDA(Laser Doppler Anemometry) and thermocouples, respectively. And flow fields are visualized by taking pictures of the flow region with suspended particles. The results show the occurrence of a very effective circulation of the fluid in the whole flow area as the heater and coolers are put into operation. In the remote region below the heated plate the flow is nearly stagnant, and a remarkable temperature stratification can be observed with very thin thermal boundary. Analytical predictions using the FLUTAN code show a reasonable matching of the measured velocity fields. 18 figs., 2 tabs., 18 refs. (Author)

  7. City sewer collectors biocorrosion

    Science.gov (United States)

    Ksiażek, Mariusz

    2014-12-01

    This paper presents the biocorrosion of city sewer collectors impregnated with special polymer sulphur binders, polymerized sulphur, which is applied as the industrial waste material. The city sewer collectors are settled with a colony of soil bacteria which have corrosive effects on its structure. Chemoautotrophic nitrifying bacteria utilize the residues of halites (carbamide) which migrate in the city sewer collectors, due to the damaged dampproofing of the roadway and produce nitrogen salts. Chemoorganotrophic bacteria utilize the traces of organic substrates and produce a number of organic acids (formic, acetic, propionic, citric, oxalic and other). The activity of microorganisms so enables the origination of primary and secondary salts which affect physical properties of concretes in city sewer collectors unfavourably.

  8. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  9. Thermal analysis of building roof assisted with water heater and ...

    Indian Academy of Sciences (India)

    D Prakash

    2018-03-14

    Mar 14, 2018 ... Thermal analysis; building roof; solar water heating system; roof ... These solar collec- ... several benefits, such as its wide range of storage temper- ... rugated plate, rear plate and back insulation material [12]. ..... [7] Weiss W and Rommel M 2008 Process heat collectors. State of the art within Task 33/IV.

  10. Water experiments on thermal striping in reactor vessel of advanced sodium-cooled fast reactor. Influence of flow collector of backup CR guide tube

    International Nuclear Information System (INIS)

    Kobayashi, Jun; Ezure, Toshiki; Tanaka, Masaaki; Kamide, Hideki

    2016-01-01

    Design study of an advanced large-scale sodium-cooled fast reactor (SFR) has been conducted in JAEA. In the region between the bottom of the Upper Internal Structure (UIS) and the core outlet, the hot sodium from the fuel subassembly mixes with the cold sodium from the neighbor control rod (CR) channel. Therefore, temperature fluctuation due to mixing fluids at different temperatures may cause high cycle thermal fatigue at the bottom of the UIS. In the advanced design, installation of a flow guide structure named Flow-Collector (FC) to the backup control rod (BCR) guide tube is considered to enhance reliable operation of self-actuated shutdown system (SASS) and to ensure reactor shutdown operation. Previously, water experiments without the FC model had been examined in JAEA to investigate effective countermeasures to the significant temperature fluctuation generation at the bottom of the UIS. Since the FC may affect the thermal mixing behavior at the bottom of the UIS, influence of the FC on characteristics of the temperature fluctuation around the BCR channels was investigated using a water experimental facility with structure model of the FC. Through the experiment, small influence of the FC on the temperature fluctuation distribution at the bottom of the UIS was indicated. (author)

  11. Movable air solar collector and its efficiency

    International Nuclear Information System (INIS)

    Lauva, A.; Aboltinš, A.; Palabinskis, J.; Karpova Sadigova, N.

    2008-01-01

    Implementing the guidelines of the Latvian National Programme for Energy in the field of alternative energy, intensive research shall be carried on regarding the use of solar energy, as it can be successfully used not only for the purposes of water heating and production of electrical energy, but also for air warming. The amount of heat necessary for the drying of rough forage and grain drying by active aeration in June, July and August can be obtained using solar radiation. The Latvian Guidelines for the Energy Development 2006-2016 state that the solar radiance in Latvia is of quite low intensity. The total amount of solar energy is 1109 kWh m -2 per year. The period of usage of the solar thermal energy is beginning from the last decade of April, when the intensity of radiation is 120 kWh m -2 , until the first decade of September. Within this period (approximately 1800 hours), it is possible to use the solar thermal energy by placing solar collectors. The usage of solar collectors for in drying of agricultural production is topical from the viewpoint of decreasing the consumption of energy used for the drying, as electrical energy and fossil energy resources become more expensive and tend to run out. In the processes that concern drying of agricultural production, efficiently enough solar radiation energy can be used. Due to this reason researching continues and expands in the field of usage of solar energy for the processes of drying and heating. The efficiency factor of the existing solar collectors is not high, but they are of simple design and cheep for production and exploitation. By improving the design of the solar collectors and choosing modern materials that absorb the solar radiation energy, it is possible the decrease the efficiency factor of solar collectors and decrease the production costs. In the scientific laboratory of grain drying and storage of Latvia University of Agriculture, a pilot device movable folding solar collector pilot device

  12. Study of the effect of water vapor on a resistive plate chamber with glass electrodes

    CERN Document Server

    Sakai, H H; Teramoto, Y; Nakano, E E; Takahashi, T T

    2002-01-01

    We studied the effects of water vapor on the efficiencies of resistive plate chambers with glass electrodes, operated in the streamer mode. With moisture in the chamber gas that has freon as a component (water vapor approx 1000 ppm), a decrease in the efficiency (approx 20%) has been observed after operating for a period of several weeks to a few months. From our study, the cause of the efficiency decrease was identified as a change on the cathode surface. In addition, a recovery method was found: flushing for 1 day with argon bubbled through water containing >=3% ammonia, followed by a few weeks of training with dry gas.

  13. Multiple-effect diffusion solar still coupled with a vacuum-tube collector and heat pipe

    KAUST Repository

    Chong, Tze-Ling

    2014-08-01

    The present study develops a multiple-effect diffusion solar still (MEDS) with a bended-plate design in multiple-effect diffusion unit (MDU) to solve the peel-off problem of wick material. The MDU is coupled with a vacuum-tube solar collector to produce a high temperature gradient for high productivity. A heat pipe is used to transfer the solar heat to the MDU. A prototype MEDS-1L was built and tested outdoors. Four performance indexes are proposed for the performance evaluation of MEDS, including daily pure water production per unit area of glass cover, solar absorber, and evaporating surface (Mcov, Msol, Mevp, respectively), and solar distillation efficiency Rcov. The outdoor test results of MEDS-1L show that the solar collector supply temperature Th reaches 100°C at solar radiation 800Wm-2. The highest Mcov is 23.9kgm-2d-1 which is about 29% higher than the basin-type MEDS [11]. The highest value is 25.9kgm-2d-1 for Msol and 2.79kgm-2d-1 for Mevp. The measured Rcov is 1.5-2.44, higher than the basin-type MEDS (1.45-1.88). The Mcov, Msol, Mevp and Rcov of MEDS-1L are all higher than the theoretical calculation of a MEDS with a flat-plate solar collector coupled with a heat pipe (MEDS-FHP) [17].© 2014 Elsevier B.V.

  14. Large zero-tension plate lysimeters for soil water and solute collection in undisturbed soils

    Directory of Open Access Journals (Sweden)

    A. Peters

    2009-09-01

    Full Text Available Water collection from undisturbed unsaturated soils to estimate in situ water and solute fluxes in the field is a challenge, in particular if soils are heterogeneous. Large sampling devices are required if preferential flow paths are present. We present a modular plate system that allows installation of large zero-tension lysimeter plates under undisturbed soils in the field. To investigate the influence of the lysimeter on the water flow field in the soil, a numerical 2-D simulation study was conducted for homogeneous soils with uni- and bimodal pore-size distributions and stochastic Miller-Miller heterogeneity. The collection efficiency was found to be highly dependent on the hydraulic functions, infiltration rate, and lysimeter size, and was furthermore affected by the degree of heterogeneity. In homogeneous soils with high saturated conductivities the devices perform poorly and even large lysimeters (width 250 cm can be bypassed by the soil water. Heterogeneities of soil hydraulic properties result into a network of flow channels that enhance the sampling efficiency of the lysimeter plates. Solute breakthrough into zero-tension lysimeter occurs slightly retarded as compared to the free soil, but concentrations in the collected water are similar to the mean flux concentration in the undisturbed soil. To validate the results from the numerical study, a dual tracer study with seven lysimeters of 1.25×1.25 m area was conducted in the field. Three lysimeters were installed underneath a 1.2 m filling of contaminated silty sand, the others deeper in the undisturbed soil. The lysimeters directly underneath the filled soil material collected water with a collection efficiency of 45%. The deeper lysimeters did not collect any water. The arrival of the tracers showed that almost all collected water came from preferential flow paths.

  15. Experimental investigations of hybrid PV/Spiral flow thermal collector system performance using Al2O3/water nanofluid

    Science.gov (United States)

    Gangadevi, R.; Vinayagam, B. K.; Senthilraja, S.

    2017-05-01

    In this paper, the PV/T (Photovoltaic thermal unit) system is investigated experimentally to examine the thermal, electrical and overall efficiency by circulating Al2O3/water nanofluid of 1wt% and 2wt% with an optimum flow rate of 40L/H. The overall efficiency of PVT system is largely influenced by various factors such as heat due to photovoltaic action; energy radiated at the infrared wavelength of the solar spectrum, solar irradiance, mounting structure, tilt angle, wind speed direction, Ambient temperature and panel material composition. However, the major factor is considered in this study to extract the heat generated in the PV panel by using nanofluid as a coolant to increase the overall system efficiency. Therefore, the result shows that by using 2 wt% Al2O3/water nanofluid the electrical efficiency, thermal efficiency and overall efficiency of the PVT system enhanced by 13%, 45%, and 58% respectively compared with water.

  16. Cavitation inception in nozzle-plate and wire mesh pressure droppers in water and sodium

    International Nuclear Information System (INIS)

    Collinson, A.E.

    1976-01-01

    Cavitation tests on multi-hole nozzle plates and wire meshes approximately 100mm diameter in water at 20 deg C and sodium at 300 deg C are described. These pressure dropping elements were mounted in recirculating loops where cavitation was induced by gradually lowering the back-ground pressure at constant flow. Cavitation was detected acoustically using wall mounted piezoelectric microphones, the signal being displayed on a ratemeter recording individual cavitation events. For nozzle plates, cavitation started intermittently as the pressure was lowered, the noise level suddenly increasing at a critical cavitation number sigma. For meshes the intermittent region was absent. Values of sigma for nozzles and meshes were similar in water and sodium for the conditions prevailing during the tests. It was apparent that cavitation took place on the axes of vortices both in the free stream and close to nozzle curved surfaces

  17. Performance of a LiBr water absorption chiller operating with plate heat exchangers

    OpenAIRE

    Vega Blázquez, Mercedes de; Almendros Ibáñez, José Antonio; Ruiz, G.

    2006-01-01

    This paper studies the performance of a lithium bromide water absorption chiller operating with plate heat exchangers (PHE). The overall heat transfer coefficients in the desorber, the condenser and the solution heat recoverer are calculated using the correlations provided in the literature for evaporation, condensation and liquid to liquid heat transfer in PHEs. The variable parameters are the external driving temperatures. In the desorber, the inlet temperature of the hot fluid ranges from ...

  18. A solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Vasil' yev, L.L.; Avakyan, Yu.V.; Bogdanov, V.M.; Gagiyan, L.A.; Grakovich, L.P.; Karapetyan, G.S.; Morgun, V.A.

    1984-01-01

    A collector whose primary component is a heating pipe is proposed. The evaporation zone located in the lower half of the heating pipe has an external absorption coating. Chambers that open upward and contain the evaporating fluid are mounted within this region along the top. In order to improve operational reliability of the collector, these chambers are mounted on one coated wall; the area of projection of each of the chambers onto the horizontal plane is greater than the area of the projection of each of the chambers placed above it. The coating may be in the form of photocells; a filter is mounted on the chamber side inside the evaporation zone. The evaporation zone may take the form of a cylinder with a segmented base; the photocells are mounted on a flat section of the lateral surface. The collector may be used to cool the photocells.

  19. Preliminary design package for solar collector and solar pump

    Science.gov (United States)

    1978-01-01

    A solar-operated pump using an existing solar collector, for use on solar heating and cooling and hot water systems is described. Preliminary design criteria of the collector and solar-powered pump is given including: design drawings, verification plans, and hazard analysis.

  20. Advances in design of air-heating collectors

    CSIR Research Space (South Africa)

    Johannsen, A

    1982-11-01

    Full Text Available Principles of the operation of air-heating collectors are discussed. The fundamental differences between the design principles of air-heating as opposed to water-heating collectors are highlighted. The main requirement is the transfer of heat from...

  1. Fit for purpose validated method for the determination of the strontium isotopic signature in mineral water samples by multi-collector inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Brach-Papa, Christophe; Van Bocxstaele, Marleen; Ponzevera, Emmanuel [European Commission - Joint Research Centre - Institute for Reference Materials and Measurements, Retieseweg 111 - 2440 Geel (Belgium); Quetel, Christophe R. [European Commission - Joint Research Centre - Institute for Reference Materials and Measurements, Retieseweg 111 - 2440 Geel (Belgium)], E-mail: christophe.quetel@ec.europa.eu

    2009-03-15

    A robust method allowing the routine determination of n({sup 87}Sr)/n({sup 86}Sr) with at least five significant decimal digits for large sets of mineral water samples is described. It is based on 2 consecutive chromatographic separations of Sr associated to multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements. Separations are performed using commercial pre-packed columns filled with 'Sr resin' to overcome isobaric interferences affecting the determination of strontium isotope ratios. The careful method validation scheme applied is described. It included investigations on all parameters influencing both chromatographic separations and MC-ICPMS measurements, and also the test on a synthetic sample made of an aliquot of the NIST SRM 987 certified reference material dispersed in a saline matrix to mimic complex samples. Correction for mass discrimination was done internally using the n({sup 88}Sr)/n({sup 86}Sr) ratio. For comparing mineral waters originating from different geological backgrounds or identifying counterfeits, calculations involved the well known consensus value (1/0.1194) {+-} 0 as reference. The typical uncertainty budget estimated for these results was 40 'ppm' relative (k = 2). It increased to 150 'ppm' (k = 2) for the establishment of stand alone results, taking into account a relative difference of about 126 'ppm' systematically observed between measured and certified values of the NIST SRM 987. In case there was suspicion of a deviation of the n({sup 88}Sr)/n({sup 86}Sr) ratio (worst case scenario) our proposal was to use the NIST SRM 987 value 8.37861 {+-} 0.00325 (k = 2) as reference, and assign a typical relative uncertainty budget of 300 'ppm' (k = 2). This method is thus fit for purpose and was applied to eleven French samples.

  2. Evaluation of initial collector field performance at the Langley Solar Building Test Facility

    Science.gov (United States)

    Boyle, R. J.; Knoll, R. H.; Jensen, R. N.

    1977-01-01

    The thermal performance of the solar collector field for the NASA Langley Solar Building Test Facility is given for October 1976 through January 1977. An 1180 square meter solar collector field with seven collector designs helped to provide hot water for the building heating system and absorption air conditioner. The collectors were arranged in 12 rows with nominally 51 collectors per row. Heat transfer rates for each row are calculated and recorded along with sensor, insolation, and weather data every 5 minutes using a mini-computer. The agreement between the experimental and predicted collector efficiencies was generally within five percentage points.

  3. Solar water lifter

    Energy Technology Data Exchange (ETDEWEB)

    Khandurdyyev, A; Daykhanov, S; Itayev, K I; Kurbanov, N

    1982-01-01

    A water lifter is described which contains a diaphram pump with working cavity and inlet and outlet valves and solar energy collector filled with easily boiling fluid. In order to improve the degree of use of the solar energy and output, the water lifter additionally contains a bellows arranged in the working cavity of the pump and connected to it and the collector, and a cylinder made of magnetic-soft material with a magnetic valve arranged in it with a rod connected to the bellows, a seat for the valve on the upper end and contact plate interacting with the valve in its lower position.

  4. Characterization of gold and nickel coating on AISI 304 stainless steel for use in the fabrication of current collector plates for fuel cells; Caracterizacion de recubrimientos de oro y niquel realizados sobre acero inoxidable AISI 304 para su empleo en la fabricacion de placas colectoras de corriente para celdas de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Flores Hernandez, J. Roberto [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)] e-mail: jrflores@iie.org.mx; Aguilar Gama, M. Tulio [UNAM. Facultad de Quimica, Mexico D.F. (Mexico); Cano Castillo, Ulises; Albarran, Lorena [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Olvera, J. Carlos; Orozco, German [CIDETEQ, Pedro Escobedo, Queretaro (Mexico)

    2009-09-15

    Among the different components that compose fuel cell technology (MEA, bipolar plates, seals, etc.) current collector plates play an important role in the good performance of fuel cells, since they collect all of the current generated and distribute it to the external circuit. Therefore, the most important properties that the current collector plates should have are excellent conductivity and good resistance to the corrosive conditions present in the fuel cell. This document presents results obtained during the nickel and gold electrodeposition process on AISI 304 stainless steel and the morphology and thickness of each coating, their adhesion, hardness and conductivity values. Finally, results obtained during some of the electrochemical tests performed on the coatings are shown. [Spanish] De los diferentes componentes que integran la tecnologia de celdas de combustible (MEA's, placas bipolares, sellos, etc.), las placas colectoras de corriente tienen un importante rol en el buen desempeno de la celdas de combustibles, ya que en estas placas se colecta toda la corriente generada y se distribuye al circuito externo. Debido a esto, las propiedades mas importantes que deben tener las placas colectaras de corriente son: excelente conductividad y buena resistencia a las condiciones corrosivas presentes en la celda de combustible. En este documento se presentan los resultados obtenidos en el proceso de electrodeposicion de niquel y oro sobre acero inoxidable AISI 304, asi como la morfologia y el espesor de cada recubrimiento, sus valores de adherencia, dureza y conductividad. Finalmente se muestran tambien los resultados obtenidos de algunas pruebas electroquimicas a los que fueron sometidos los recubrimientos.

  5. Solar collector manufacturing activity, 1990

    International Nuclear Information System (INIS)

    1992-01-01

    The Solar Collector Manufacturing Activity 1990 report prepared by the Energy Information Administration (EIA) presents summary and detailed data provided by domestic manufacturers on shipments of solar thermal collectors and photovoltaic cells and modules. Summary data on solar thermal collector shipments are presented for the period 1974 through 1990. Summary data on photovoltaic cell and module shipments are presented for the period 1982 through 1990. Detailed information for solar thermal collectors and photovoltaic cells and modules are presented for 1990

  6. Solar energy collector

    Science.gov (United States)

    Brin, Raymond L.; Pace, Thomas L.

    1978-01-01

    The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

  7. Qualification test and analysis report: solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    Test results show that the Owens-Illinois Sunpak/sup TM/ Model SEC 601 air-cooled collector meets the national standards and codes as defined in the Subsystem Performance Specification and Verification Plan of NASA/MSFC Contract NAS8-32259, dated October 28, 1976. The architectural and engineering firm of Smith, Hinchman and Grylls, Detroit, Michigan, acted in the capacity of the independent certification agency. The program calls for the development, fabrication, qualification and delivery of an air-liquid solar collector for solar heating, combined heating and cooling, and/or hot water systems.

  8. Heat Pumps With Direct Expansion Solar Collectors

    Science.gov (United States)

    Ito, Sadasuke

    In this paper, the studies of heat pump systems using solar collectors as the evaporators, which have been done so far by reserchers, are reviwed. Usually, a solar collector without any cover is preferable to one with ac over because of the necessity of absorbing heat from the ambient air when the intensity of the solar energy on the collector is not enough. The performance of the collector depends on its area and the intensity of the convective heat transfer on the surface. Fins are fixed on the backside of the collector-surface or on the tube in which the refrigerant flows in order to increase the convective heat transfer. For the purpose of using a heat pump efficiently throughout year, a compressor with variable capacity is applied. The solar assisted heat pump can be used for air conditioning at night during the summer. Only a few groups of people have studied cooling by using solar assisted heat pump systems. In Japan, a kind of system for hot water supply has been produced commercially in a company and a kind of system for air conditioning has been installed in buildings commercially by another company.

  9. Comparison of Adsorption of Phenol O-O and N-O Chelating Collectors at the Malachite/Water Interface in Flotation

    Directory of Open Access Journals (Sweden)

    Zhili Li

    2017-02-01

    Full Text Available To separate one base metal mineral from another by flotation, it is indispensable to identify chemical reagents that specifically interact with the surface metal sites of one mineral or a group of minerals. This work studies the interactions of chelating collectors which offer the best potential for collecting abilities and mineral specificity with a typical refractory oxide mineral (malachite. Zeta potential, adsorption and Fourier transform infrared (FTIR measurements are applied to differentiate the interactions of salicylaldoxime and salicyl hydroxamate on the malachite surface. Salicylaldoxime and salicyl hydroxamate are of molecular structures that resemble each other, but with different bond distances in the ligand atoms which result in their unusual adsorption behavior and collecting ability. Thus, the flotation of malachite behaves differently with the two chelating collectors. This study might provide useful clues for designing novel collectors in base metal oxide flotations.

  10. Aging and characterization of PVC compound used as flat-panel of a low cost solar collector; Envelhecimento e caracterizacao de compostos de PVC usado em placas de coletores solares de baixo custo

    Energy Technology Data Exchange (ETDEWEB)

    Prado, Bruna R.; Pinto, Tatiana T.; Bartoli, Julio R. [Depto. de Tecnologia de Polimeros, Faculdade de Engenharia Quimica/Universidade Estadual de Campinas. FEQ/UNICAMP, SP (Brazil)], e-mail: bartoli@feq.unicamp.br; Fernandes, Elizabeth G. [Tezca P and D Celulas Solares (Brazil)

    2011-07-01

    Regardless the excellent amount of solar irradiation in Brazil, the development and production of solar water heating systems did not reach the low-income families yet. The relatively high cost of conventional solar water heaters is still the main reason to prevent it. The development of a low cost solar water heater (around US$ 200), easy technology, was the scope of previous work. All-plastic solar collector prototypes were developed using unplasticized Poly (vinyl chloride) ceiling panels and tubes, commodities from building engineering. Nevertheless, the main thermal and photo degradation mechanisms for PVC are well known; the unusual application of PVC as solar collector materials should need a specific investigation on environmental aging. This work presents a study on outdoor aging and characterization of PVC flat-plate absorber of solar collectors after 5 years on use. (author)

  11. Energy and exergy analysis of photovoltaic-thermal collector with and without glass cover

    International Nuclear Information System (INIS)

    Chow, T.T.; Pei, G.; Fong, K.F.; Lin, Z.; Chan, A.L.S.; Ji, J.

    2009-01-01

    In photovoltaic-thermal (PV/T) technology, the use of glass cover on the flat-plate hybrid solar collector is favorable to the photothermic process but not to the photovoltaic process. Because of the difference in the usefulness of electricity and thermal energy, there is often no straight forward answer on whether a glazed or unglazed collector system is more suitable for a specific application. This glazing issue was tackled in this paper from the viewpoint of thermodynamics. Based on experimental data and validated numerical models, a study of the appropriateness of glass cover on a thermosyphon-based water-heating PV/T system was carried out. The influences of six selected operating parameters were evaluated. From the first law point of view, a glazed PV/T system is found always suitable if we are to maximize the quantity of either the thermal or the overall energy output. From the exergy analysis point of view however, the increase of PV cell efficiency, packing factor, water mass to collector area ratio, and wind velocity are found favorable to go for an unglazed system, whereas the increase of on-site solar radiation and ambient temperature are favorable for a glazed system

  12. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    Directory of Open Access Journals (Sweden)

    M. Norhafana

    2015-11-01

    Full Text Available Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved. KEYWORDS: solar water heating system; solar collector; multilayered absorber; solar simulator; solar radiation 

  13. Relation between the amount of dissolved water and metals dissolved from stainless steel or aluminum plate in safflower oil

    Energy Technology Data Exchange (ETDEWEB)

    Takasago, Masahisa; Takaoka, Kyo

    1986-12-01

    The amount of water dissolved in safflower oil at the frying temperature (180 deg C) was 518 -- 1012 ppM, allowing water to drop continuously (0.035 g/2 min) into the oil for 1 -- 3 h. When the oil was heated with metal plates under the same conditions, the amount of dissolved water in the oil increased more than in the absence of the metal plates. In case of stainless steel, the amount was 1.26 to 1.33 times, and with aluminum plates, 1.06 to 1.13 times the amount without plates. When these metal plates were heated with the oil under the above conditions, the water dissolved the metal of the plates into the oil. In case of stainless steel, iron dissolved from 0.17 to 0.77 ppM, nickel, 0.04 ppM and chromium, from 0.02 to 0.03 ppM. Similarly, the amount of aluminum dissolved from the aluminum plate was from 0.10 to 0.45 ppM.

  14. The relation between the amount of dissolved water and metals dissolved from stainless steel or aluminum plate in safflower oil

    International Nuclear Information System (INIS)

    Takasago, Masahisa; Takaoka, Kyo

    1986-01-01

    The amount of water dissolved in safflower oil at the frying temperature (180 deg C) was 518 ∼ 1012 ppm, allowing water to drop continuously (0.035 g/2 min) into the oil for 1 ∼ 3 h. When the oil was heated with metal plates under the same conditions, the amount of dissolved water in the oil increased more than in the absence of the metal plates. In case of stainless steel, the amount was 1.26 to 1.33 times, and with aluminum plates, 1.06 to 1.13 times the amount without plates. When these metal plates were heated with the oil under the above conditions, the water dissolved the metal of the plates into the oil. In case of stainless steel, iron dissolved from 0.17 to 0.77 ppm, nickel, 0.04 ppm and chromium, from 0.02 to 0.03 ppm. Similarly, the amount of aluminum dissolved from the aluminum plate was from 0.10 to 0.45 ppm. (author)

  15. Performance Analysis of a Thermoelectric Solar Collector Integrated with a Heat Pump

    Science.gov (United States)

    Lertsatitthanakorn, C.; Jamradloedluk, J.; Rungsiyopas, M.; Therdyothin, A.; Soponronnarit, S.

    2013-07-01

    A novel heat pump system is proposed. A thermoelectric solar collector was coupled to a solar-assisted heat pump (TESC-HP) to work as an evaporator. The cooling effect of the system's refrigerant allowed the cold side of the system's thermoelectric modules to work at lower temperature, improving the conversion efficiency. The TESC-HP system mainly consisted of transparent glass, an air gap, an absorber plate that acted as a direct expansion-type collector/evaporator, an R-134a piston-type hermetic compressor, a water-cooled plate-type condenser, thermoelectric modules, and a water storage tank. Test results indicated that the TESC-HP has better coefficient of performance (COP) and conversion efficiency than the separate units. For the meteorological conditions in Mahasarakham, the COP of the TESC-HP system can reach 5.48 when the average temperature of 100 L of water is increased from 28°C to 40°C in 60 min with average ambient temperature of 32.5°C and average solar intensity of 815 W/m2, whereas the conversion efficiency of the TE power generator was around 2.03%.

  16. Investigation of methods to transfer heat from solar liquid-heating collectors to heat storage tanks

    Energy Technology Data Exchange (ETDEWEB)

    de Winter, F.

    1976-01-01

    A number of possible solutions to the problems of corrosion and freezing in flat-plate collectors are listed and discussed briefly. Specific considerations involved in the choice and definition of these solutions are discussed in greater detail. (MHR)

  17. Effect of radiation on convective flow in a tilted solar collector filled ...

    African Journals Online (AJOL)

    user

    International Journal of Engineering, Science and Technology. Vol. 4, No. 4, 2012, pp ... The flat-plate solar collector is commonly used today for the collection of low .... Outside the boundary layer, the amount of energy reflected q is neglected.

  18. Solar collector array

    Science.gov (United States)

    Hall, John Champlin; Martins, Guy Lawrence

    2015-09-06

    A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.

  19. Studi Kinerja Solar Water Heater Dengan Aliran Zig-zag Beralur Balok

    OpenAIRE

    Ikhsan, M. Rizki; Soeparman, Sudjito; Sasongko, Mega Nur

    2017-01-01

    Solar energy can be used for water heating by using solar water heater application. Therefore, its still needs some modification due to its low efficiency. This modification can be done by replacing the conventional plate of solar collectors into a double plate with a zig-zag pattern. The results shown that along with the decreasing of water flow rates could significantly increase the useful energy (Qu). Initial temperature of water inlet could affect the generated maximum temperature. The hi...

  20. Thermal analysis of gyrotron traveling-wave tube collector

    International Nuclear Information System (INIS)

    Zheng Zhiqing; Luo Yong; Jiang Wei; Tang Yong

    2013-01-01

    In order to solve cooling problem of the gyrotron traveling-wave tube(TWT) collector and guarantee the gyrotron TWT's reliability and stability, the electron trajectories in the gyrotron TWT are simulated using CST electron simulation software. Thermal analysis of the collector with finite element software ANSYS is performed. The ways of applying boundary that affects the distribution of collector temperature are compared. The influence of the water temperature and flow rate on collector temperature distribution under actual heat fluxes (boundary condition) is researched. The size and number of collector fins are optimized, and a relatively perfect structure is obtained finally. The result estimated by simulation is consistent with the experiment and proves that the model and method employed in this work are suitable. (authors)

  1. Molecular dynamics simulations of ultrathin water film confined between flat diamond plates

    Directory of Open Access Journals (Sweden)

    A.V. Khomenko

    2008-12-01

    Full Text Available Molecular dynamics simulations of ultrathin water film confined between atomically flat rigid diamond plates are described. Films with thickness of one and two molecular diameters are concerned and TIP4P model is used for water molecules. Dynamical and equilibrium characteristics of the system for different values of the external load and shear force are investigated. An increase of the external load causes the transition of the film to a solidlike state. This is manifested in a decrease of the diffusion constant and in the ordering of the liquid molecules into quasidiscrete layers. For two-layer film under high loads, the molecules also become ordered parallel to the surfaces. Time dependencies of the friction force and the changes of its average value with the load are obtained. In general, the behaviour of the studied model is consistent with the experimental results obtained for simple liquids with spherical molecules.

  2. Effects of different collector’s area on the coupling of a thermosiphon collector and a single zone

    International Nuclear Information System (INIS)

    Chargui, R.; Sammouda, H.

    2014-01-01

    Graphical abstract: - Highlights: • We simulate a thermosiphon collector associated to a single zone using TRNSYS. • We examine the temperature of water in collector, in tank and in single zone. • We study the temporal evolution of the temperature and the energy for 11 h operation in January and 2880 h operation in winter. • The system gives good results in all operating states. • The use of solar energy in the residential building is interesting. - Abstract: The novelty of this paper is the coupling between a thermosiphon collector and a single zone with the following details; a thermosiphon system (TYPE 45) which uses the solar energy as an unlimited renewable energy to produce the heat by using an internal coupling of a flat plate collector and a storage tank in a closed loop realized in TRNSYS. Consequently, the user simply utilizes TYPE 45 as thermosiphon ready to be run, and a single zone (TYPE 19) is a complex type which is designed for residential buildings that can be specified by the user in order to obtain an acceptable heating within a house. The user specified the characteristics of the internal space, external weather conditions, walls, windows, and doors. To facilitate this description, the parameters and inputs for this component are organized in separate table according to a logical structure. According to us, the choice of this model of thermosiphon coupled with a single zone can have multiple interesting engineering applications, in particular ameliorating the mode of the heating in residential buildings. Two flat plate collectors of aperture area of 6 and 8 m 2 are modeled. The solar fraction of the entire system is used as the optimization parameter. The temperature of the water in the storage tank, the collector’s temperature, the temperature inside and outside the house, the solar fraction for different collector areas and the total energy were also measured in 11 h operation in January and 2880 h operation in winter. The average

  3. Performance of double -pass solar collector with CPC and fins for heat transfer enhancement

    Science.gov (United States)

    Alfegi, Ebrahim M. A.; Abosbaia, Alhadi A. S.; Mezughi, Khaled M. A.; Sopian, Kamaruzzaman

    2013-06-01

    The temperature of photovoltaic modules increases when it absorbs solar radiation, causing a decrease in efficiency. This undesirable effect can be partially avoided by applying a heat recovery unit with fluid circulation (air or water) with the photovoltaic module. Such unit is called photovoltaic / thermal collector (pv/t) or hybrid (pv/t). In this unit, photovoltaic cells were pasted directly on the flat plate absorber. An experimental study of a solar air heater with photovoltaic cell located at the absorber with fins and compound parabolic collector for heat transfer enhancement and increasing the number of reflection on the cells have been conducted. The performance of the photovoltaic, thermal, and combined pv/t collector over range of operating conditions and the results was discussed. Results at solar irradiance of 500 W/m2 show that the combined pv/t efficiency is increasing from 37.28 % to 81.41 % at mass flow rates various from 0.029 to 0.436 kg/s.

  4. Performance of double –pass solar collector with CPC and fins for heat transfer enhancement

    International Nuclear Information System (INIS)

    Alfegi, Ebrahim M A; Abosbaia, Alhadi A S; Mezughi, Khaled M A; Sopian, Kamaruzzaman

    2013-01-01

    The temperature of photovoltaic modules increases when it absorbs solar radiation, causing a decrease in efficiency. This undesirable effect can be partially avoided by applying a heat recovery unit with fluid circulation (air or water) with the photovoltaic module. Such unit is called photovoltaic / thermal collector (pv/t) or hybrid (pv/t). In this unit, photovoltaic cells were pasted directly on the flat plate absorber. An experimental study of a solar air heater with photovoltaic cell located at the absorber with fins and compound parabolic collector for heat transfer enhancement and increasing the number of reflection on the cells have been conducted. The performance of the photovoltaic, thermal, and combined pv/t collector over range of operating conditions and the results was discussed. Results at solar irradiance of 500 W/m 2 show that the combined pv/t efficiency is increasing from 37.28 % to 81.41 % at mass flow rates various from 0.029 to 0.436 kg/s.

  5. Drilling and cutting of thin metal plates in water with radiation of a repetitively pulsed Nd : YAG laser

    Energy Technology Data Exchange (ETDEWEB)

    Glova, A F; Lysikov, A Yu [State Research Center of Russian Federation ' Troitsk Institute for Innovation and Fusion Research' , Troitsk, Moscow Region (Russian Federation)

    2011-10-31

    The conditions of drilling and cutting of 0.15-mm-thick titanium and stainless steel plates in water with the radiation of a repetitively pulsed Nd : YAG laser having the mean power up to 30 W are studied experimentally in the absence of water and gas jets. Dependences of the maximal cutting speed in water on the radiation power are obtained, the cutting efficiency is determined, and the comparison with the conditions of drilling and cutting of plates in air is carried out.

  6. Flow cytometric bacterial cell counts challenge conventional heterotrophic plate counts for routine microbiological drinking water monitoring

    KAUST Repository

    Van Nevel, S.

    2017-02-08

    Drinking water utilities and researchers continue to rely on the century-old heterotrophic plate counts (HPC) method for routine assessment of general microbiological water quality. Bacterial cell counting with flow cytometry (FCM) is one of a number of alternative methods that challenge this status quo and provide an opportunity for improved water quality monitoring. After more than a decade of application in drinking water research, FCM methodology is optimised and established for routine application, supported by a considerable amount of data from multiple full-scale studies. Bacterial cell concentrations obtained by FCM enable quantification of the entire bacterial community instead of the minute fraction of cultivable bacteria detected with HPC (typically < 1% of all bacteria). FCM measurements are reproducible with relative standard deviations below 3% and can be available within 15 min of samples arriving in the laboratory. High throughput sample processing and complete automation are feasible and FCM analysis is arguably less expensive than HPC when measuring more than 15 water samples per day, depending on the laboratory and selected staining procedure(s). Moreover, many studies have shown FCM total (TCC) and intact (ICC) cell concentrations to be reliable and robust process variables, responsive to changes in the bacterial abundance and relevant for characterising and monitoring drinking water treatment and distribution systems. The purpose of this critical review is to initiate a constructive discussion on whether FCM could replace HPC in routine water quality monitoring. We argue that FCM provides a faster, more descriptive and more representative quantification of bacterial abundance in drinking water.

  7. Flow cytometric bacterial cell counts challenge conventional heterotrophic plate counts for routine microbiological drinking water monitoring

    KAUST Repository

    Van Nevel, S.; Koetzsch, S.; Proctor, C.R.; Besmer, M.D.; Prest, E.I.; Vrouwenvelder, Johannes S.; Knezev, A.; Boon, N.; Hammes, F.

    2017-01-01

    Drinking water utilities and researchers continue to rely on the century-old heterotrophic plate counts (HPC) method for routine assessment of general microbiological water quality. Bacterial cell counting with flow cytometry (FCM) is one of a number of alternative methods that challenge this status quo and provide an opportunity for improved water quality monitoring. After more than a decade of application in drinking water research, FCM methodology is optimised and established for routine application, supported by a considerable amount of data from multiple full-scale studies. Bacterial cell concentrations obtained by FCM enable quantification of the entire bacterial community instead of the minute fraction of cultivable bacteria detected with HPC (typically < 1% of all bacteria). FCM measurements are reproducible with relative standard deviations below 3% and can be available within 15 min of samples arriving in the laboratory. High throughput sample processing and complete automation are feasible and FCM analysis is arguably less expensive than HPC when measuring more than 15 water samples per day, depending on the laboratory and selected staining procedure(s). Moreover, many studies have shown FCM total (TCC) and intact (ICC) cell concentrations to be reliable and robust process variables, responsive to changes in the bacterial abundance and relevant for characterising and monitoring drinking water treatment and distribution systems. The purpose of this critical review is to initiate a constructive discussion on whether FCM could replace HPC in routine water quality monitoring. We argue that FCM provides a faster, more descriptive and more representative quantification of bacterial abundance in drinking water.

  8. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  9. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Chen, Ziqian; Furbo, Simon

    2009-01-01

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  10. The CERN antiproton collector

    International Nuclear Information System (INIS)

    Autin, B.

    1984-01-01

    The Antiproton Collector is a new ring of much larger acceptance than the present accumulator. It is designed to receive 10 8 antiprotons per PS cycle. In order to be compatible with the Antiproton Accumulator, the momentum spread and the emittances are reduced from 6% to 0.2% and from 200 π mm mrad to 25 π mm mrad respectively. In addition to the ring itself, the new target area and the modifications to the stochastic systems of the Antiproton Accumulator are described. (orig.)

  11. Air solar collectors in building use - A review

    Science.gov (United States)

    Bejan, Andrei-Stelian; Labihi, Abdelouhab; Croitoru, Cristiana; Catalina, Tiberiu

    2018-02-01

    In the current energy and environmental context it is imperative to implement systems based on renewable energy sources in order to reduce energy consumptions worldwide. Solar collectors are studied by many years and many researchers are focusing their attention in order to increase their efficiency and cost-effectiveness. Water solar collectors are often implemented for domestic hot water, heating or industrial processes and already have a place on the market. A promising system which is not yet widely known is represented by air solar collectors that could represent an efficient way to use the solar energy with a lower investment cost, a system that can be used in order to preheat the fresh air required for heating, drying, or to maintain a minimum temperature during winter. This paper presents a comprehensive literature review on air solar collectors used mainly in buildings, acting as a solar wall. Air solar collectors are roughly classified into two types: glazed and opaque. The present study comprises the solar collector classification, applications and their main parameters with a special focus on opaque solar collectors.

  12. Air solar collectors in building use - A review

    Directory of Open Access Journals (Sweden)

    Bejan Andrei-Stelian

    2018-01-01

    Full Text Available In the current energy and environmental context it is imperative to implement systems based on renewable energy sources in order to reduce energy consumptions worldwide. Solar collectors are studied by many years and many researchers are focusing their attention in order to increase their efficiency and cost-effectiveness. Water solar collectors are often implemented for domestic hot water, heating or industrial processes and already have a place on the market. A promising system which is not yet widely known is represented by air solar collectors that could represent an efficient way to use the solar energy with a lower investment cost, a system that can be used in order to preheat the fresh air required for heating, drying, or to maintain a minimum temperature during winter. This paper presents a comprehensive literature review on air solar collectors used mainly in buildings, acting as a solar wall. Air solar collectors are roughly classified into two types: glazed and opaque. The present study comprises the solar collector classification, applications and their main parameters with a special focus on opaque solar collectors.

  13. Visualization of the contact line during the water exit of flat plates

    Science.gov (United States)

    Tassin, A.; Breton, T.; Forest, B.; Ohana, J.; Chalony, S.; Le Roux, D.; Tancray, A.

    2017-08-01

    We investigate experimentally the time evolution of the wetted surface during the lifting of a body initially floating at the water surface. This phenomenon is referred to as the water exit problem. The water exit experiments were conducted with transparent (PMMA) mock-ups of two different shapes: a circular disc and a square flat plate. Two different lighting systems were used to diffuse light in the mock-up material: a central high-power LED light normal to the surface and an edge-lighting system featuring an array of LED lights. These setups make it possible to illuminate the contact line, which delimits the surface of contact between the mock-up and the water. The characteristic size of the mock-ups is about 20 cm and the acceleration of the mock-up oscillates between 0 and 25 m/s^2. We show that the central light setup gives satisfactory results for the circular disc and that the edge lighting technique makes it possible to follow a contact line with a time-evolving complex shape (strong changes of convexity) up to 1000 fps. The observations presented in the paper support the possibility of extending this promising technique to more general three-dimensional bodies with arbitrary motion (e.g., including pitch motion).

  14. Water, oceanic fracture zones and the lubrication of subducting plate boundaries—insights from seismicity

    Science.gov (United States)

    Schlaphorst, David; Kendall, J.-Michael; Collier, Jenny S.; Verdon, James P.; Blundy, Jon; Baptie, Brian; Latchman, Joan L.; Massin, Frederic; Bouin, Marie-Paule

    2016-03-01

    We investigate the relationship between subduction processes and related seismicity for the Lesser Antilles Arc using the Gutenberg-Richter law. This power law describes the earthquake-magnitude distribution, with the gradient of the cumulative magnitude distribution being commonly known as the b-value. The Lesser Antilles Arc was chosen because of its along-strike variability in sediment subduction and the transition from subduction to strike-slip movement towards its northern and southern ends. The data are derived from the seismicity catalogues from the Seismic Research Centre of The University of the West Indies and the Observatoires Volcanologiques et Sismologiques of the Institut de Physique du Globe de Paris and consist of subcrustal events primarily from the slab interface. The b-value is found using a Kolmogorov-Smirnov test for a maximum-likelihood straight line-fitting routine. We investigate spatial variations in b-values using a grid-search with circular cells as well as an along-arc projection. Tests with different algorithms and the two independent earthquake cataloges provide confidence in the robustness of our results. We observe a strong spatial variability of the b-value that cannot be explained by the uncertainties. Rather than obtaining a simple north-south b-value distribution suggestive of the dominant control on earthquake triggering being water released from the sedimentary cover on the incoming American Plates, or a b-value distribution that correlates with on the obliquity of subduction, we obtain a series of discrete, high b-value `bull's-eyes' along strike. These bull's-eyes, which indicate stress release through a higher fraction of small earthquakes, coincide with the locations of known incoming oceanic fracture zones on the American Plates. We interpret the results in terms of water being delivered to the Lesser Antilles subduction zone in the vicinity of fracture zones providing lubrication and thus changing the character of the

  15. Solar space and water heating system at Stanford University Central Food Services Building. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    This active hydronic domestic hot water and space heating system was 840 ft/sup 2/ of single-glazed, liquid, flat plate collectors and 1550 gal heat storage tanks. The following are discussed: energy conservation, design philosophy, operation, acceptance testing, performance data, collector selection, bidding, costs, economics, problems, and recommendations. An operation and maintenance manual and as-built drawings are included in appendices. (MHR)

  16. Solar warming systems of water installed in Colombia. Photovoltaic solar systems installed in the Country

    International Nuclear Information System (INIS)

    Rodriguez P, F.

    1995-01-01

    Between the systems that operate as of solar energy, the solar collectors to heat water have had wide use and application in the Country. Basically, a solar collector is constituted by: Box, thermal insulator, ducts and transparent roof. Generally, the used materials are the following: As thermal insulator: Polyurethane or glass fiber; as absorbent plate: Copper or aluminum, painting in dull black or selective surfaces; for the ducts: Generally it is used copper pipeline; and for the cover: Common glass or temperate glass

  17. Exergy analysis of integrated photovoltaic thermal solar water heater under constant flow rate and constant collection temperature modes

    NARCIS (Netherlands)

    Tiwari, A.; Dubey, Swapnil; Sandhu, G.S.; Sodha, M.S.; Anwar, S.I.

    2009-01-01

    In this communication, an analytical expression for the water temperature of an integrated photovoltaic thermal solar (IPVTS) water heater under constant flow rate hot water withdrawal has been obtained. Analysis is based on basic energy balance for hybrid flat plate collector and storage tank,

  18. The PKI collector

    Science.gov (United States)

    Rice, M. P.

    1982-07-01

    The design and manufacturing of a solar thermal collector is discussed. The collector has three primary subsystems: concentrator, receiver/fluid loop, and controls. Identical curved reflective columns are utilized in a faceted Fresnel design to support 864 one foot square flat inexpensive second-surface, silvered glass mirrors. The columns are ganged together and rotated through their centers of gravity to provide elevation tracking. The concentrator is supported by a lightweight spaceframe structure which distributes all wind and gravity loads to the base supports. The base of the structure is a track which rotates on wheels mounted on concrete piers. A parallel tube steel heat exchanger is mounted at the concentrator focal area in a well insulated, galvanized steel housing. Two rows of vertical close-packed, staggered tubes connect a mud header and a steam header. Automatic two axis tracking and operational control is provided with a microprocessor based package. Concentrator-mounted shadowbands are the basis for active tracking. A software program provides azimuthal tracking during cloudy periods.

  19. A Study on the Development of Nonglass Solar Vacuum Tube Collector

    International Nuclear Information System (INIS)

    Oh, Seung Jin

    2008-02-01

    Nature has been providing us energy from the beginning of the world. However human has hardly used it wisely. Solar energy is a kind of renewable energy from the nature. This study has been carried out to study the use of solar energy as it is harnessed in the form of thermal energy. Solar energy is one of the most promising energy resources such as hydrogen, biomass, wind and geothermal energy, because it is clean and inexhaustible. Space heating in buildings can be provided from solar energy by systems that are similar in many respects to water heater systems. By tapping into solar energy, we can not only solve the problem of energy shortage, but also can protect the environment and benefit the human beings. There are currently two types of evacuated tube; a single glass tube and a double glass tube. The former consists of a single glass tube which contains a flat or curved aluminium plate attached to a copper heat pipe or water flow pipe. The latter consists of rows of parallel transparent glass tubes, each of which contains an absorber tube. Evacuated tube collectors introduced above, however, pose some problems as they break rather easily under mechanical stresses. This paper introduces some preliminary results in design and fabrication of a non-glass solar vacuum tube collector in which the thermosyphon(heat pipe)made of copper is used as a heat transfer device. A series of tests have been performed to assess the ability of a non-glass solar vacuum tube collector. The series of experiments are as follows: 1)Vacuum level inside a vacuum tube. 2)Effects of the air remaining inside a vacuum tube on the temperature on the absorber plate. 3)Comparison of a non-glass vacuum solar collector with a single glass evacuated tube(SEIDO 5). Different vacuum levels inside non-glass vacuum tubes were applied to check any leakage or unexpected physical or chemical developments with time. The vacuum level changed from 10 -2 torr to 5torr in 5 days due to air infiltration from

  20. The effective removal method of copper and cyanide in waste water of metal plating factories

    International Nuclear Information System (INIS)

    Jae, Won Mok; Hong, Zong Doo; Kim, Myun Sup

    1988-01-01

    To investigate the effective removal method of cooper and cyanide compounds in metal plating waste water, removal ratio of cooper and cyanide compounds in solution are measured with varying pH, concentration and contact time. As results of the present experiment, cyanide compounds in the solution are removed to 0.03mg/l or less with 5% NaOCl solution. The present result is satisfied to environmental disposal standards. The removal ratio against pH values show 99% over pH8. As results of neutral precipitation method, copper including solution are removed to 99% at pH8 in short time. The removal ratios of cyanide mixed copper solution against pH values show high efficiency(over 95%) at pH8 and 11 and removal ratios are decreased at pH10.(Author)

  1. Water resistant rhodium plated reflectors for use in the DIRC BaBar Cherenkov detector

    CERN Document Server

    Benkebil, M; Plaszczynski, S; Schune, M H; Wormser, G

    2000-01-01

    Early simulation studies showed that reflectors mounted on the photomultipliers would be useful for the DIRC BaBar Cherenkov detector, showing a gain between 20% and 30% in the number of Cherenkov photons. The proof of principle for these reflectors has been obtained during the beam test of a large-scale prototype of the DIRC detector. An extensive R and D has been conducted in order to test different metallization procedures. Indeed, the challenge was to find a metallization technique which can resist the pure de-ionized water (>15 M OMEGA) up to 10 yr. The chosen technology was rhodium plated reflectors. During the first BaBar cosmic run, the measured performance confirmed the results of the simulation, the prototype-II and the R and D.

  2. Boundary Layer Flow and Heat Transfer of FMWCNT/Water Nanofluids over a Flat Plate

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Safaei

    2016-09-01

    Full Text Available In the present study, the heat transfer and flow of water/FMWCNT (functionalized multi-walled carbon nanotube nanofluids over a flat plate was investigated using a finite volume method. Simulations were performed for velocity ranging from 0.17 mm/s to 1.7 mm/s under laminar regime and nanotube concentrations up to 0.2%. The 2-D governing equations were solved using an in-house FORTRAN code. For a specific free stream velocity, the presented results showed that increasing the weight percentage of nanotubes increased the Nusselt number. However, an increase in the solid weight percentage had a negligible effect on the wall shear stress. The results also indicated that increasing the free stream velocity for all cases leads to thinner boundary layer thickness, while increasing the FMWCNT concentration causes an increase in the boundary layer thickness.

  3. Nickel removal from nickel plating waste water using a biologically active moving-bed sand filter.

    Science.gov (United States)

    Pümpel, Thomas; Macaskie, Lynne E; Finlay, John A; Diels, Ludo; Tsezos, Marios

    2003-12-01

    Efficient removal of dissolved nickel was observed in a biologically active moving-bed 'MERESAFIN' sand filter treating rinsing water from an electroless nickel plating plant. Although nickel is fully soluble in this waste water, its passage through the sand filter promoted rapid removal of approximately 1 mg Ni/l. The speciation of Ni in the waste water was modelled; the most probable precipitates forming under the conditions in the filter were predicted using PHREEQC. Analyses of the Ni-containing biosludge using chemical, electron microscopical and X-ray spectroscopic techniques confirmed crystallisation of nickel phosphate as arupite (Ni3(PO4)2 x 8H2O), together with hydroxyapatite within the bacterial biofilm on the filter sand grains. Biosorption contributed less than 1% of the overall sequestered nickel. Metabolising bacteria are essential for the process; the definitive role of specific components of the mixed population is undefined but the increase in pH promoted by metabolic activity of some microbial components is likely to promote nickel desolubilisation by others.

  4. Heat transfer from a plate cooled by a water film with countercurrent air flow

    International Nuclear Information System (INIS)

    Ambrosini, W.; Manfredini, A.; Mariotti, F.; Oriolo, F.; Vigni, P.

    1995-01-01

    An experimental program at the University of Pisa provides specific data for the evaluation of heat and mass transfer by falling film evaporation. The problem is addressed primarily because of its relevance to the study of the behavior of passive containment cooling systems in simplified pressurized water reactors. In these plants, after an accident that releases vapor from the primary circuit, the steel containment envelope is cooled either by an ascending stream of air in natural circulation or by the combination of air flow and falling film evaporation. To qualify models for the prediction of the heat transfer capabilities in postulated accident conditions, researchers have built an experimental facility consisting of a flat heated plate with water sprays and a fan to simulate a countercurrent air stream. The range of relevant parameters to be investigated has been determined on the basis of integral calculations performed for the AP600 reactor containment. The facility has enabled the collection of data that confirm the adequacy of the classical heat and mass transfer analogy in predicting evaporation phenomena. Further developments in the research are needed to confirm the first results and to extend the experimental database by considering more subtle aspects of the phenomenon such as the characteristics of surface waviness of the water film and its effect on heat transfer

  5. Usage of hybrid solar collector system in drying technologies of medical plants

    International Nuclear Information System (INIS)

    Čiplienė, Aušra; Novošinskas, Henrikas; Raila, Algirdas; Zvicevičius, Egidijus

    2015-01-01

    Highlights: • Solar radiation energy utilization in drying technologies. • Accumulation of solar radiation energy. • The system comprising two different solar collector types. • Preparation of the drying agent by employing solar radiation energy around the clock. • The energy resources saving technology for medicinal plants’ raw material processing and drying. - Abstract: In the temperate climate zone under natural conditions, medicinal plants drying up to 8–12% moisture content and preparation of the quality medicinal plant’s raw material are complicated tasks. In many cases drying process of medicinal plants raw material, particularly rich in volatile compounds, needs the optimal drying temperatures of 30–45 °C and relative humidity not higher than 50–60%. In Lithuania, located in the northern part of the temperate climate zone, in summer the average temperature of ambient air is 16.1 ± 0.5 °C, and relative humidity is 77.3 ± 1.8%. In order to improve the sorption properties of ambient air, it is heated up to the admissible drying temperature. The experimental dryer was developed comprising two different solar collectors: the air type solar collector with area 12 m 2 for direct heating of the drying agent and the flat-plate type solar collector (8 m 2 ) for accumulation of converted heat energy. The research of motherwort (Leonurus cardiaca L.) drying was carried out in the dryer. It was determined that by combining operation of two different solar collectors, the solar radiation energy for drying agent’s heating could be used continuously around the clock by employing the accumulated energy, in order to compensate the solar irradiance variability and to ensure stability of the drying process. In the daytime the air-type solar collector at an airflow equal to 367 m 3 h −1 , i.e. at comparative flow of the drying agent per ton of dried medicinal plant raw material – 2450 m 3 h −1 , heats the air up to 30 °C when the solar

  6. Numerical investigation of coalescing plate system to understand the separation of water and oil in water treatment plant of petroleum industry

    Directory of Open Access Journals (Sweden)

    Sedat Yayla

    2017-01-01

    Full Text Available The most widely utilized process of produced water treatment is considered to be use of coalescing or corrugated plate systems in the oil industry because these systems have promising results in the acceleration of the separation process. Even use of corrugated plate systems seem to be effective in separation processes, the geometrical parameters of the plate system could greatly influence the performance of separation process. In this study, a two-dimensional computational fluid dynamics model for coalescing plates was developed to investigate Reynolds number and plate hole shape on separation efficiency. Spacing between plates was set to 12 mm while fluid mixture’s Reynolds number varied between 5 and 45 for the computational model. Hole profile and dimensions were determined to be cylindrical, rectangular and ellipse shapes as 10, 15 and 20 mm based on hydraulic diameter definition, respectively. Furthermore, when hole profiles of coalescing plates were chosen to be ellipse and rectangular shapes, separation efficiency nearly stayed constant regardless of hole dimension. The study also reported that change of oil fraction from 5% to 15% caused approximately 30% increase in the separation efficiency. The investigation also revealed Reynolds number of the mixture was inversely proportional to the separation efficiency. It was also found that the highest separation efficiency was obtained for a cylindrical shape with a hole diameter of 15 mm when distance between plates was 12 mm and Reynolds number was 18.

  7. A heat pipe solar collector system for winter heating in Zhengzhou city, China

    Directory of Open Access Journals (Sweden)

    Zheng Hui-Fan

    2017-01-01

    Full Text Available A heat pipe solar collector system for winter heating is investigated both experimentally and theoretically. The hourly heat collecting capacity, water temperature and contribution rate of solar collector system based on Zhengzhou city typical sunshine are calculated. The study reveals that the heat collecting capacity and water temperature increases initially and then decreases, and the solar collector system can provide from 40% to 78% heating load for a 200 m2 villa with in Zhengzhou city from November to March.

  8. LHCb Tag Collector

    International Nuclear Information System (INIS)

    Fernández, Paloma Fuente; Clemencic, Marco; Cousin, Nicolas

    2011-01-01

    The LHCb physics software consists of hundreds of packages, each of which is developed by one or more physicists. When the developers have some code changes that they would like released, they commit them to the version control system, and enter the revision number into a database. These changes have to be integrated into a new release of each of the physics analysis applications. Tests are then performed by a nightly build system, which rebuilds various configurations of the whole software stack and executes a suite of run-time functionality tests. A Tag Collector system has been developed using solid standard technologies to cover both the use cases of developers and integration managers. A simple Web interface, based on an AJAX-like technology, is available. Integration with SVN and Nightly Build System, is possible via a Python API. Data are stored in a relational database with the help of an ORM (Object-Relational Mapping) library.

  9. Advanced evacuated tube collectors

    Science.gov (United States)

    Schertz, W. W.; Hull, J. R.; Winston, R.; Ogallagher, J.

    1985-04-01

    The essence of the design concept for these new collectors is the integration of moderate levels of nonimaging concentration inside the evacuated tube itself. This permanently protects the reflection surfaces and allows the use of highly reflecting front surface mirrors with reflectances greater than 95%. Previous fabrication and long term testing of a proof-of-concept prototype has established the technical success of the concept. Present work is directed toward the development of a manufacturable unit that will be suitable for the widest possible range of applications. Design alternatives include scaling up the original prototype's tube diameter from 5 cm to 10 cm, using an internal shaped metal concentrating reflector, using a variety of profile shapes to minimize so-called gap losses and accommodate both single ended and double-ended flow geometries, and allowing the use of heat pipes for the absorber tube.

  10. Performance of Partially Covered N Number of Photovoltaic Thermal (PVT) - Compound Parabolic Concentrator (CPC) Series Connected Water Heating System

    OpenAIRE

    Rohit Tripathi; Sumit Tiwari; G. N. Tiwari

    2016-01-01

    In present study, an approach is adopted where photovoltaic thermal flat plate collector is integrated with compound parabolic concentrator. Analytical expression of temperature dependent electrical efficiency of N number of partially covered Photovoltaic Thermal (PVT) - Compound Parabolic Concentrator (CPC) water collector connected in series has been derived with the help of basic thermal energy balance equations. Analysis has been carried for winter weather condition at Delhi location, Ind...

  11. One-year assessment of a solar space/water heater--Clinton, Mississippi

    Science.gov (United States)

    1981-01-01

    Unit called "System 4" integrated into space-heating and hot-water systems of dormitory satisfied 32 percent of building heat load. System 4 includes flat-plate air collectors, circulation blowers, rock storage bed with heat exchanger, two hot water tanks, and auxiliary heaters. Report describes performance of system and subsystems, operating-energy requirements and savings, and performance parameters.

  12. Pathogenic features of heterotrophic plate count bacteria from drinking-water boreholes.

    Science.gov (United States)

    Horn, Suranie; Pieters, Rialet; Bezuidenhout, Carlos

    2016-12-01

    Evidence suggests that heterotrophic plate count (HPC) bacteria may be hazardous to humans with weakened health. We investigated the pathogenic potential of HPC bacteria from untreated borehole water, consumed by humans, for: their haemolytic properties, the production of extracellular enzymes such as DNase, proteinase, lipase, lecithinase, hyaluronidase and chondroitinase, the effect simulated gastric fluid has on their survival, as well as the bacteria's antibiotic-susceptible profile. HuTu-80 cells acted as model for the human intestine and were exposed to the HPC isolates to determine their effects on the viability of the cells. Several HPC isolates were α- or β-haemolytic, produced two or more extracellular enzymes, survived the SGF treatment, and showed resistance against selected antibiotics. The isolates were also harmful to the human intestinal cells to varying degrees. A novel pathogen score was calculated for each isolate. Bacillus cereus had the highest pathogen index: the pathogenicity of the other bacteria declined as follows: Aeromonas taiwanensis > Aeromonas hydrophila > Bacillus thuringiensis > Alcaligenes faecalis > Pseudomonas sp. > Bacillus pumilus > Brevibacillus sp. > Bacillus subtilis > Bacillus sp. These results demonstrated that the prevailing standards for HPCs in drinking water may expose humans with compromised immune systems to undue risk.

  13. Flow Regimes of Air-Water Counterflow Through Cross Corrugated Parallel Plates

    Energy Technology Data Exchange (ETDEWEB)

    de Almeida, V.F.

    2000-06-07

    Heretofore unknown flow regimes of air-water counterflow through a pair of transparent vertical parallel cross corrugated plates were observed via high-speed video. Air flows upward driven by pressure gradient and water, downward driven by gravity. The crimp geometry of the corrugations was drawn from typical corrugated sheets used as filling material in modern structured packed towers. Four regimes were featured, namely, rivulet, bicontinuous, flooding fronts, and flooding waves. It is conceivable that the regimes observed might constitute the basis for understanding how gas and liquid phases contend for available space in the interstices of structured packings in packed towers. Flow regime transitions were expressed in terms of liquid load (liquid superficial velocity) and gas flow factor parameters commonly used in pressure drop and capacity curves. We have carefully examined the range of parameters equivalent to the ill-understood high-liquid-flow operation in packed towers. More importantly, our findings should prove valuable in validating improved first-principles modeling of gas-liquid flows in these industrially important devices.

  14. Water and Electricity Do Mix: Studying Plates, Petroleum, and Permafrost using Marine Electromagnetism

    Science.gov (United States)

    Constable, S.

    2015-12-01

    Marine magnetotelluric (MT) and controlled-source electromagnetic (CSEM) sounding methods were developed in the early 1980's as deep-water academic tools to study the oceanic lithosphere and mantle. Electrical conductivity is a strong function of porosity, temperature, melting, and volatile content, and so marine MT and CSEM data can be used to address a variety of geological questions related to plate tectonics. These include the distribution of melt at mid-ocean ridges, the fate of fluids in subduction zones, and the nature of the lithosphere-asthenosphere boundary. With the advent of deepwater oil and gas drilling in the late 1990's, marine EM methods were embraced by the exploration community, and are now routinely used to assist in exploration and make drilling decisions for wells costing $100M or more. For countries without conventional hydrocarbon resources, gas hydrate offers the potential for energy production, and marine CSEM methods may be the only effective way to explore for and characterize this resource. The use of EM methods to map geothermal, groundwater, and mineral resources also has application in the marine environment. Water and electricity has proved to be a very successful mix!

  15. Performance of a LiBr-water absorption chiller operating with plate heat exchangers

    International Nuclear Information System (INIS)

    Vega, M. de; Almendros-Ibanez, J.A.; Ruiz, G.

    2006-01-01

    This paper studies the performance of a lithium bromide-water absorption chiller operating with plate heat exchangers (PHE). The overall heat transfer coefficients in the desorber, the condenser and the solution heat recoverer are calculated using the correlations provided in the literature for evaporation, condensation and liquid to liquid heat transfer in PHEs. The variable parameters are the external driving temperatures. In the desorber, the inlet temperature of the hot fluid ranges from 75 deg. C to 105 deg. C. In the condenser and the absorber, the inlet temperature of the cooling water goes from 20 deg. C to 40 deg. C. The coefficient of performance (COP) obtained ranges from 0.5 to 0.8 for cooling duties ranging from 2 kW to 12 kW. The chiller response to different hot fluid temperatures and circulated mass flow rates is also presented. The performance and the internal parameters of the chiller at part load are, therefore, calculated. A higher efficiency results when the solution pumped from the absorber to the desorber decreases. The heat transfer analysis of the PHEs is also presented. The overall heat transfer coefficient in the desorber, equal to 790 W/m 2 K at the design conditions, is also analysed at part load. The condenser performance can be represented by a similar relationship found in conventional air cooled condensers

  16. An experimental investigation with artificial sunlight of a solar hot-water heater

    Science.gov (United States)

    Simon, F. F.

    1976-01-01

    Thermal performance measurements were made of a commercial solar hot water heater in a solar simulator to determine basic performance characteristics of a traditional type of flat plate collector, with and without side reflectors (to increase the solar flux). Information on each of the following was obtained; (1) the effect of flow and incidence angle on the efficiency of a flat plate collector (but only without side reflectors); (2) transient performance under flow and nonflow conditions; (3) the effectiveness of reflectors to increase collector efficiency for a zero radiation angle at fluid temperatures required for solar air conditioning; and (4) the limits of applicability of a collector efficiency correlation based on the Hottel Whillier equation.

  17. Compilation of publication and results from project C2: Modelling of microclimates in collectors

    Energy Technology Data Exchange (ETDEWEB)

    Holck, O. [ed.

    1999-08-01

    It is important to avoid condensation in solar collectors, most of all because wetness of the absorber can damage the selective surface and cause corrosion on the absorber plate. During night time the cover of collectors will cool below ambient temperature due to thermal radiation to the cold sky. In climates where the air during night time becomes saturated with humidity (the relative humidity is 100%), condensation will form on the outside and inside of the collector glazing. If too much condensation takes place on the inside of the glazing, it will start to fall off on to the absorber surface. The intent of the present work is improvement of a existing computer model for calculation of microclimates data in collectors. Calculations with the model give insight in the humidity and temperature for artificial or realistic climatic data. This design tool makes it possible to calculate the effect of ventilation and insulation materials. Results from investigation of ventilation rates together with a model of the moisture inside the collector are built into the computer program. It has been found that modelling of the moisture transfer in backside insulation is essential to determine the humidity in the air gap of the collector. The objective is to develop guidelines for solar collector design to achieve the most favourable microclimates condition for materials. As a tool the computer model will be useful to fulfil this. Guidelines for collectors will be essential for manufactures to improve the long-term durability of solar collectors. (au)

  18. Flat solar collector an approach to its evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Sonino, T [Israel Atomic Energy Commission, Yavne. Soreq Nuclear Research Center

    1977-01-01

    The flat solar collector is the most widely used device for the utilization of solar energy, but its energetic and economic values are still debated. A preliminary energy and economic analysis is presented. The energy analysis indicates that the energy needed to produce one solar collector is equivalent to the electricity consumed by an electric water heater in roughly three months. The economic analysis indicates that the pay-back time for a solar collector varies from 5.5 to 7.7 yr. according to the discount rate. The economic analysis from a national point of view indicates that the use of solar collectors for domestic purposes could only reduce electricity consumption in Israel by 10%.

  19. Investigation of a hybrid PVT air collector system

    Science.gov (United States)

    Haddad, S.; Touafek, K.; Mordjaoui, M.; Khelifa, A.; Tabet, I.

    2017-02-01

    The photovoltaic thermal hybrid (PVT) collectors, which simultaneously produce electricity and heat, are an alternative to photovoltaic modules and thermal collectors installed separately. Indeed, the heat extracted from the solar cell is used to heat water or air, thereby cooling the cell, and thus increasing its energy efficiency. This paper deals with a hybrid PVT air collector in which a new design has been proposed and tested. Its principle is based on the return of the preheating air to a second heating. The air thus passes twice under the solar cells before being evacuated to the outside of the collector (for space heating). The system is modular and expandable to cover large spaces to be heated. The experimental results of this novel design are presented and discussed under both normal and forced circulation. This technique of air return shows favorable results in terms of the quality of the heated air and electric power generation.

  20. Development of Low-Cost Solar Water Heater Using Recycled Solid Waste for Domestic Hot Water Supply

    Directory of Open Access Journals (Sweden)

    Talib Din Abdul

    2018-01-01

    Full Text Available This research is focused on the development of a low-cost solar water heater (SWH system by utilizing solid waste material as part of system elements. Available technologies of the solar water heater systems, heat collectors and its components were reviewed and the best system combinations for low cost design were chosen. The passive-thermosiphon system have been chosen due to its simplicity and independency on external power as well as conventional pump. For the heat collector, flat plate type was identified as the most suitable collector for low cost design and suits with Malaysia climate. Detail study on the flat plate collector components found that the heat absorber is the main component that can significantly reduce the solar collector price if it is replaced with recycled solid waste material. Review on common solid wastes concluded that crushed glass is a non-metal material that has potential to either enhance or become the main heat absorber in solar collector. A collector prototype were then designed and fabricated based on crashed glass heat collector media. Thermal performance test were conducted for three configurations where configuration A (black painted aluminum absorber used as benchmark, configuration B (crushed glass added partially that use glass for improvement, and lastly configuration C (black colored crushed glass that use colored glass as main absorber. Result for configuration B have shown a negative effect where the maximum collector efficiency is 26.8% lower than configuration A. Nevertheless, configuration C which use black crushed glass as main heat absorber shown a comparable maximum efficiency which is at 82.5% of the maximum efficiency for configuration A and furthermore have shown quite impressive increment of efficiency at the end of the experiment. Hence, black colored crushed glass is said to have quite a good potential as the heat absorber material and therefore turn out to be a new contender to other non

  1. Current collectors for improved safety

    Science.gov (United States)

    Abdelmalak, Michael Naguib; Allu, Srikanth; Dudney, Nancy J.; Li, Jianlin; Simunovic, Srdjan; Wang, Hsin

    2017-12-19

    A battery electrode assembly includes a current collector with conduction barrier regions having a conductive state in which electrical conductivity through the conduction barrier region is permitted, and a safety state in which electrical conductivity through the conduction barrier regions is reduced. The conduction barrier regions change from the conductive state to the safety state when the current collector receives a short-threatening event. An electrode material can be connected to the current collector. The conduction barrier regions can define electrical isolation subregions. A battery is also disclosed, and methods for making the electrode assembly, methods for making a battery, and methods for operating a battery.

  2. AEROSOL PARTICLE COLLECTOR DESIGN STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S; Richard Dimenna, R

    2007-09-27

    A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

  3. Four-collector flux sensor

    International Nuclear Information System (INIS)

    Wiegand, W.J. Jr.; Bullis, R.H.; Mongeon, R.J.

    1980-01-01

    A flowmeter based on ion drift techniques was developed for measuring the rate of flow of a fluid through a given cross-section. Ion collectors are positioned on each side of an immediately adjacent to ion source. When air flows axially through the region in which ions are produced and appropriate electric fields are maintained between the collectors, an electric current flows to each collector due to the net motion of the ions. The electric currents and voltages and other parameters which define the flow are combined in an electric circuit so that the flux of the fluid can be determined. (DN)

  4. Combined solar collector and storage systems

    International Nuclear Information System (INIS)

    Norton, B.; Smyth, M.; Eames, P.; Lo, S.N.G.

    2000-01-01

    The article discusses reasons why fossil-fuelled water heating systems are included in new houses but solar systems are not. The technology and market potential for evacuated tube systems and integral collector storage systems (ICSS) are explained. The challenge for the designers of ICSSWH has been how to reduce heat loss without compromising solar energy collection. A new concept for enhanced energy storage is described in detail and input/output data are given for two versions of ICSSWH units. A table compares the costs of ICSSWH in houses compared with other (i.e. fossil fuel) water heating systems

  5. Theoretical analysis to investigate thermal performance of co-axial heat pipe solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Azad, E. [Iranian Research Organization for Science and Technology (IROST), Advanced Materials and Renewable Energy Department, Tehran (Iran, Islamic Republic of)

    2011-12-15

    The thermal performance of co-axial heat pipe solar collector which consist of a collector 15 co-axial heat pipes surrounded by a transparent envelope and which heat a fluid flowing through the condenser tubes have been predicted using heat transfer analytical methods. The analysis considers conductive and convective losses and energy transferred to a fluid flowing through the collector condenser tubes. The thermal performances of co-axial heat pipe solar collector is developed and are used to determine the collector efficiency, which is defined as the ratio of heat taken from the water flowing in the condenser tube and the solar radiation striking the collector absorber. The theoretical water outlet temperature and efficiency are compared with experimental results and it shows good agreement between them. The main advantage of this collector is that inclination of collector does not have influence on performance of co-axial heat pipe solar collector therefore it can be positioned at any angle from horizontal to vertical. In high building where the roof area is not enough the co-axial heat pipe solar collectors can be installed on the roof as well as wall of the building. The other advantage is each heat pipe can be topologically disconnected from the manifold. (orig.)

  6. Theoretical analysis to investigate thermal performance of co-axial heat pipe solar collector

    Science.gov (United States)

    Azad, E.

    2011-12-01

    The thermal performance of co-axial heat pipe solar collector which consist of a collector 15 co-axial heat pipes surrounded by a transparent envelope and which heat a fluid flowing through the condenser tubes have been predicted using heat transfer analytical methods. The analysis considers conductive and convective losses and energy transferred to a fluid flowing through the collector condenser tubes. The thermal performances of co-axial heat pipe solar collector is developed and are used to determine the collector efficiency, which is defined as the ratio of heat taken from the water flowing in the condenser tube and the solar radiation striking the collector absorber. The theoretical water outlet temperature and efficiency are compared with experimental results and it shows good agreement between them. The main advantage of this collector is that inclination of collector does not have influence on performance of co-axial heat pipe solar collector therefore it can be positioned at any angle from horizontal to vertical. In high building where the roof area is not enough the co-axial heat pipe solar collectors can be installed on the roof as well as wall of the building. The other advantage is each heat pipe can be topologically disconnected from the manifold.

  7. Solar water heating for small cheese factories in Peru

    Energy Technology Data Exchange (ETDEWEB)

    Oliveros Donohue, A A

    1982-03-01

    Plans are described for the implementation of 40 small plants to be used for cheese production. As a start, a demonstration plant has been built in San Juan de Chuquibambilla-Puno, Peru. Design and testing of a flat plate solar collector, to be used for water heating purposes, are described. The cheese making process is discussed. Essentially two pots are required, one at 32/sup 0/C and one at 80/sup 0/. Two flat plate collectors (1.12 m/sup 2/ each) are connected to a 150 l storage tank. Instrumentation and results are discussed. Total efficiency of the process is given as 40%. It is concluded that future installations should consider using biogas digesters and wind driven water pumps in addition to the solar collectors. A brief discussion of the climate, population distribution, and economy of Peru is given. (MJJ)

  8. Influence of reflectance from flat aluminum concentrators on energy efficiency of PV/Thermal collector

    International Nuclear Information System (INIS)

    Kostic, Ljiljana T.; Pavlovic, Tomislav M.; Pavlovic, Zoran T.

    2010-01-01

    In this paper the results of the influence of reflectance from flat plate solar radiation concentrators made of Al sheet and Al foil on energy efficiency of PV/Thermal collector are presented. The total reflectance from concentrators made of Al sheet and Al foil is almost the same, but specular reflectance which is bigger in concentrators made of Al foil results in increase of solar radiation intensity concentration factor. With the increase of solar radiation intensity concentration factor, total daily thermal and electrical energy generated by PV/Thermal collector with concentrators increase. In this work also optimal position of solar radiation concentrators made of Al sheet and Al foil and appropriate thermal and electrical efficiency of PV/Thermal collector have been determined. Total energy generated by PV/Thermal collector with concentrators made of Al foil in optimal position is higher than total energy generated by PV/Thermal collector with concentrators made of Al sheet.

  9. Solar powered adsorption refrigerator with CPC collection system: Collector design and experimental test

    International Nuclear Information System (INIS)

    Gonzalez, Manuel I.; Rodriguez, Luis R.

    2007-01-01

    Solar adsorption cooling systems are usually based on the flat plate collector, whereas little attention has been paid to concentrating collectors. Compound parabolic concentrators (CPC) are a versatile class of solar collectors that can be adapted to a large variety of applications and geometries. This work presents a CPC collector whose tubular receiver contains the sorption bed and where only a portion of the receiver is exposed to sunlight. Geometric characteristics of the proposed CPC, such as the profile, the length and the height of the reflective sheet are given. A prototype of a solar adsorption chiller using this type of collector and the activated carbon-methanol working pair is described, and typical experimental results are reported. In particular, the measured solar COP ranges from 0.078 to 0.096

  10. Experimental results of the consequences of sodium water reactions at the bottom tube plate region of straight tube steam generators

    International Nuclear Information System (INIS)

    Ruloff, G.

    1990-01-01

    Experience with sodium water reactions has shown, that the course of such a steam generator accident depends strongly on its place in the steam generator. For the EFR steam generators we have to differentiate between: weld region at the upper tube plate (gas space); bundle region; weld region at the bottom tube plate. This paper describes results of a running tests program simulating the bottom tube plate area. One main part of these tests is the investigation of the influence of wastage protection shrouds between the tubes in the weld region to avoid a fast leak propagation and to give time for leak detection and mastering of the accidents. (author). 10 figs, 2 tabs

  11. Experimental Investigation of a Direct Methanol Fuel Cell with Hilbert Fractal Current Collectors

    Directory of Open Access Journals (Sweden)

    Jing-Yi Chang

    2014-01-01

    Full Text Available The Hilbert curve is a continuous type of fractal space-filling curve. This fractal curve visits every point in a square grid with a size of 2×2, 4×4, or any other power of two. This paper presents Hilbert fractal curve application to direct methanol fuel cell (DMFC current collectors. The current collectors are carved following first, second, and third order Hilbert fractal curves. These curves give the current collectors different free open ratios and opening perimeters. We conducted an experimental investigation into DMFC performance as a function of the free open ratio and opening perimeter on the bipolar plates. Nyquist plots of the bipolar plates are made and compared using electrochemical impedance spectroscopy (EIS experiments to understand the phenomena in depth. The results obtained in this paper could be a good reference for future current collector design.

  12. Solar radiation on a catenary collector

    Science.gov (United States)

    Crutchik, M.; Appelbaum, J.

    1992-01-01

    A tent-shaped structure with a flexible photovoltaic blanket acting as a catenary collector is presented. The shadow cast by one side of the collector produces a shadow on the other side of the collector. This self-shading effect is analyzed. The direct beam, the diffuse, and the albedo radiation on the collector are determined. An example is given for the insolation on the collector operating on Viking Lander 1 (VL1).

  13. A distributed garbage collector for active objects

    OpenAIRE

    Puaut , Isabelle

    1993-01-01

    This paper introduces an algorithm that performs garbage collection in distributed systems of active objects (i.e., objects having their own threads of control). The proposed garbage collector is made of a set of local garbage collectors, one per node, loosely coupled to a global garbage collector. The novelties of the proposed garbage collector come from the fact that local garbage collectors need not be synchronized with each other for detecting garbage objects and that faulty communication...

  14. Solar collector performance evaluated outdoors at NASA-Lewis Research Center

    Science.gov (United States)

    Vernon, R. W.

    1974-01-01

    The study of solar reflector performance reported is related to a project in which solar collectors are to be provided for the solar heating and cooling system of an office building at NASA's Langley Research Center. The solar collector makes use of a liquid consisting of 50% ethylene glycol and 50% water. A conventional air-liquid heat exchanger is employed. Collector performance and solar insolation data are recorded along with air temperature, wind speed and direction, and relative humidity.

  15. Study of Cylindrical Honeycomb Solar Collector

    Directory of Open Access Journals (Sweden)

    Atish Mozumder

    2014-01-01

    Full Text Available We present the results of our investigation on cylindrical honeycomb solar collector. The honeycomb has been fabricated with transparent cellulose triacetate polymer sheets. Insulation characteristics of the honeycomb were studied by varying the separation between the honeycomb and the absorber plate. The optimal value of the separation was found to be 3.3 mm for which the heat transfer coefficient is 3.06 W m−2 K−1. This supports result of previous similar experiments. Further we test the honeycomb through a field experiment conducted in Delhi (28.6°N, 77°E and found that when the incident angle of the solar radiation is within 20° then the performance of the system with the honeycomb is better than the one without the honeycomb.

  16. Electrochemical Properties of Current Collector in the All-vanadium Redox Flow Battery

    International Nuclear Information System (INIS)

    Hwang, Gan-Jin; Oh, Yong-Hwan; Ryu, Cheol-Hwi; Choi, Ho-Sang

    2014-01-01

    Two commercial carbon plates were evaluated as a current collector (bipolar plate) in the all vanadium redox-flow battery (V-RFB). The performance properties of V-RFB were test in the current density of 60 mA/cm 2 . The electromotive forces (OCV at SOC 100%) of V-RFB using A and B current collector were 1.47 V and 1.54 V. The cell resistance of V-RFB using A current collector was 4.44-5.00 Ω·cm 2 and 3.28-3.75 Ω·cm 2 for charge and discharge, respectively. The cell resistance of V-RFB using B current collector was 4.19-4.42Ω·cm 2 and 4.71-5.49Ω·cm 2 for charge and discharge, respectively. The performance of V-RFB using each current collector was evaluated. The performance of V-RFB using A current collector was 93.1%, 76.8% and 71.4% for average current efficiency, average voltage efficiency and average energy efficiency, respectively. The performance of V-RFB using B current collector was 96.4%, 73.6% and 71.0% for average current efficiency, average voltage efficiency and average energy efficiency, respectively

  17. Numerical characterisation of one-step and three-step solar air heating collectors used for cocoa bean solar drying.

    Science.gov (United States)

    Orbegoso, Elder Mendoza; Saavedra, Rafael; Marcelo, Daniel; La Madrid, Raúl

    2017-12-01

    In the northern coastal and jungle areas of Peru, cocoa beans are dried using artisan methods, such as direct exposure to sunlight. This traditional process is time intensive, leading to a reduction in productivity and, therefore, delays in delivery times. The present study was intended to numerically characterise the thermal behaviour of three configurations of solar air heating collectors in order to determine which demonstrated the best thermal performance under several controlled operating conditions. For this purpose, a computational fluid dynamics model was developed to describe the simultaneous convective and radiative heat transfer phenomena under several operation conditions. The constructed computational fluid dynamics model was firstly validated through comparison with the data measurements of a one-step solar air heating collector. We then simulated two further three-step solar air heating collectors in order to identify which demonstrated the best thermal performance in terms of outlet air temperature and thermal efficiency. The numerical results show that under the same solar irradiation area of exposition and operating conditions, the three-step solar air heating collector with the collector plate mounted between the second and third channels was 67% more thermally efficient compared to the one-step solar air heating collector. This is because the air exposition with the surface of the collector plate for the three-step solar air heating collector former device was twice than the one-step solar air heating collector. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Solar water heater for NASA's Space Station

    Science.gov (United States)

    Somers, Richard E.; Haynes, R. Daniel

    1988-01-01

    The feasibility of using a solar water heater for NASA's Space Station is investigated using computer codes developed to model the Space Station configuration, orbit, and heating systems. Numerous orbit variations, system options, and geometries for the collector were analyzed. Results show that a solar water heater, which would provide 100 percent of the design heating load and would not impose a significant impact on the Space Station overall design is feasible. A heat pipe or pumped fluid radial plate collector of about 10-sq m, placed on top of the habitat module was found to be well suited for satisfying water demand of the Space Station. Due to the relatively small area required by a radial plate, a concentrator is unnecessary. The system would use only 7 to 10 percent as much electricity as an electric water-heating system.

  19. Experimental study of a water-mist jet issuing normal to a heated flat plate

    Directory of Open Access Journals (Sweden)

    Vouros Andreas

    2016-01-01

    Full Text Available A parametric experimental study on the development of a round jet spray impacting a smooth, heated, flat plate has been accomplished. The main objective of this effort was to provide information characterizing the flow structure of a developing mist jet, issuing vertically towards an upward facing, horizontal heated plate, by means of simultaneous droplet size and velocity measurements. Phase Doppler Anemometry was used, providing also information on liquid volume flux. The fine spray of small atomized droplets (0.5-5.0 μm, was generated using a medical nebulizer. Two low Reynolds number jets (Re=2952, 3773 issuing from a cylindrical pipe have been tested. The distance between the jets’ exit and the plate was 50 cm. A stainless steel non-magnetic flat plate of dimensions 1000x500x12mm3 was used as target wall. Constant heat flux boundary conditions were established during measurements. Results indicate that the heat flux from the plate is influencing the evolution of the spray jet, diminishing its velocity and turbulence. Average droplet sizes are affected little by the heat flux, although for the non-heated sprays, droplet sizes increase at locations very close to the plate. A significant effect on droplet volume flow rate is also reported.

  20. Research and Development of Heavy Wall DNV485FDU Pipeline Plate for 3500M Deep Water Pipe Applications at Shougang

    Science.gov (United States)

    Ding, Wenhua; Li, Shaopo; Li, Jiading; Li, Qun; Chen, Tieqiang; Zhang, Hai

    In recent years, there has been development of several significant pipeline projects for the transmission of oil and gas from deep water environments. The production of gas transmission pipelines for application demands heavy wall, high strength, good lower temperature toughness and good weldability. To overcome the difficulty of producing consistent mechanical property in heavy wall pipe Shougang Steel Research in cooperation with the Shougang Steel Qinhuangdao China (Shouqin) 4.3m heavy wide plate mill research was conducted.

  1. Comparative study of solar cooling systems with building-integrated solar collectors for use in sub-tropical regions like Hong Kong

    International Nuclear Information System (INIS)

    Fong, K.F.; Lee, C.K.; Chow, T.T.

    2012-01-01

    Highlights: ► Performance of building-integrated solar collectors analyzed. ► Comparisons made with solar collectors installed on roof. ► Use of building-integrated solar collectors increased the total primary consumption. ► Reduction in the building load could not compensate drop in solar collector output. ► Building-integrated solar collectors only used when roof space insufficient. -- Abstract: The performance of solar cooling systems with building-integrated (BI) solar collectors was simulated and the results compared with those having the solar collectors installed conventionally on the roof based on the weather data in Hong Kong. Two types of solar collectors and the corresponding cooling systems, namely the flat-plate collectors for absorption refrigeration and the PV panels for DC-driven vapour compression refrigeration, were used in the analysis. It was found that in both cases, the adoption of BI solar collectors resulted in a lower solar fraction (SF) and consequently a higher primary energy consumption even though the zone loads were reduced. The reduction in SF was more pronounced in the peak load season when the solar radiation was nearly parallel to the solar collector surfaces during the daytimes, especially for those facing the south direction. Indeed, there were no outputs from the BI flat-plate collectors facing the south direction between May and July. The more severe deterioration in the system performance with the BI flat-plate type collectors made them technically infeasible in terms of the energy-saving potential. It was concluded that the use of BI solar collectors in solar cooling systems should be restricted only to situations where the availability of the roof was limited or insufficient when applied in sub-tropical regions like Hong Kong.

  2. Flow distribution in a solar collector panel with horizontally inclined absorber strips

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    The objective of this work is to theoretically and experimentally investigate the flow and temperature distribution in a solar collector panel with an absorber consisting of horizontally inclined strips. Fluid flow and heat transfer in the collector panel are studied by means of computational fluid...... dynamics (CFD) calculations. Further, experimental investigations of a 12.5 m(2) solar collector panel with 16 parallel connected horizontal fins are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the backside of the absorber tubes. The measured...... rate, properties of solar collector fluid, solar collector fluid inlet temperature and collector tilt angle are shown. The flow distribution through the absorber fins is uniform if high flow rates are used. By decreased flow rate and decreased content of glycol in the glycol/water mixture used as solar...

  3. PERFORMANCE DETERIORATION OF THERMOSIPHON SOLAR FLAT PLATE WATER HEATER DUE TO SCALING

    Directory of Open Access Journals (Sweden)

    arunachala umesh chandavar

    2011-12-01

    Full Text Available 0 0 1 340 1943 International Islamic University 16 4 2279 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} The performance of Flat plate Solar Water Heater deteriorates within five to twelve years of their installation due to factors related to manufacturing, operating conditions, lack of maintenance etc. Especially, problem due to scaling is significant as it is based on quality of water used. The remaining factors are system dependent and could be overcome by quality production. Software is developed by incorporating Hottel Whillier Bliss (H-W-B equation to ascertain the effect of scaling on system efficiency in case of thermosiphon system. In case of clean thermosiphon system, the instantaneous efficiency calculated at 1000 W/m2 radiation is 72 % and it drops to 46 % for 3.7 mm scale thickness. The mass flow rate is reduced by 90 % for 3.7 mm scale thickness. Whereas, the average temperature drop of water in the tank is not critical due to considerable heat content in water under severe scaled condition.  But practically in case of major scale growth, some of the risers are likely to get blocked completely which leads to negligible temperature rise in the tank. ABSTRAK: Prestasi plat rata pemanas air suria merosot selepas lima hingga dua belas tahun  pemasangannya disebabkan faktor-faktor yang berkaitan dengan pembuatannya, cara kendaliannya, kurangnya penyelenggaraan dan sebagainya.  Terutama sekali, masalah disebabkan scaling (tembunan endapan mineral perlu diambil berat kerana ianya bergantung kepada kualiti air yang digunakan. Faktor-faktor selebihya bersandarkan sistem dan ia

  4. Use of an air collector plant for a municipal water house in South Africa; Einsatz einer Luftkollektoranlage fuer ein kommunales Wasserhaus in Suedafrika

    Energy Technology Data Exchange (ETDEWEB)

    Schroepf, Siegfried; Ettl, Rudolf [Grammer Solar GmbH, Amberg (Germany)

    2010-07-01

    A very interesting example of application for solar heating of industrial water and drinking water is the 'Water building project' in Jansenville (South Africa). There, the solarly heated water not only serves for having a shower, but also for washing clothes. The washing performance is increased by warm water. Thus less water is consumed. A major task of the project was to develop a completely self-sufficient and low-maintenance solar air-conditioning which easily and effectively covers the hot water requirement of a building with a high solar fraction. Additionally, the solar heating system supports the building with heat and air during the winter months.

  5. Comparison of plate counts, Petrifilm, dipslides, and adenosine triphosphate bioluminescence for monitoring bacteria in cooling-tower waters.

    Science.gov (United States)

    Mueller, Sherry A; Anderson, James E; Kim, Byung R; Ball, James C

    2009-04-01

    Effective bacterial control in cooling-tower systems requires accurate and timely methods to count bacteria. Plate-count methods are difficult to implement on-site, because they are time- and labor-intensive and require sterile techniques. Several field-applicable methods (dipslides, Petrifilm, and adenosine triphosphate [ATP] bioluminescence) were compared with the plate count for two sample matrices--phosphate-buffered saline solution containing a pure culture of Pseudomonas fluorescens and cooling-tower water containing an undefined mixed bacterial culture. For the pure culture, (1) counts determined on nutrient agar and plate-count agar (PCA) media and expressed as colony-forming units (CFU) per milliliter were equivalent to those on R2A medium (p = 1.0 and p = 1.0, respectively); (2) Petrifilm counts were not significantly different from R2A plate counts (p = 0.99); (3) the dipslide counts were up to 2 log units higher than R2A plate counts, but this discrepancy was not statistically significant (p = 0.06); and (4) a discernable correlation (r2 = 0.67) existed between ATP readings and plate counts. For cooling-tower water samples (n = 62), (1) bacterial counts using R2A medium were higher (but not significant; p = 0.63) than nutrient agar and significantly higher than tryptone-glucose yeast extract (TGE; p = 0.03) and PCA (p < 0.001); (2) Petrifilm counts were significantly lower than nutrient agar or R2A (p = 0.02 and p < 0.001, respectively), but not statistically different from TGE, PCA, and dipslides (p = 0.55, p = 0.69, and p = 0.91, respectively); (3) the dipslide method yielded bacteria counts 1 to 3 log units lower than nutrient agar and R2A (p < 0.001), but was not significantly different from Petrifilm (p = 0.91), PCA (p = 1.00) or TGE (p = 0.07); (4) the differences between dipslides and the other methods became greater with a 6-day incubation time; and (5) the correlation between ATP readings and plate counts varied from system to system, was poor

  6. Commissioning a Megawatt-class Gyrotron with Collector Potential Depression

    Science.gov (United States)

    Lohr, J.; Cengher, M.; Gorelov, Y. A.; Ponce, D.; Prater, R.

    2013-10-01

    A 110 GHz depressed collector gyrotron has been installed on the DIII-D tokamak. The commissioning process rapidly achieved operation at full parameters, 45 A and 94 kV total voltage, with 29 kV depression. Although short pulse, 2 ms, factory testing demonstrated 1.2 MW at 41% electrical efficiency, long pulse testing at DIII-D achieved only 33% efficiency at full power parameters, for pulse lengths up to 10 s. Maximum generated power was ~950 kW, considerably below the 1.2 MW target. During attempts to increase the power at 5 s pulse length, it was noted that the collector cooling water was boiling. This led to the discovery that 14 of the 160 cooling channels in the collector had been blocked by braze material during manufacture of the tube. The locations of blocked channels were identified using infrared imaging of the outside of the collector during rapid changes in the cooling water temperature. Despite these difficulties, the rf beam itself was of very high quality and the stray rf found calorimetrically in the Matching Optics Unit, which couples the Gaussian rf beam to the waveguide, was only 2% of the generated power, about half that of our previous best quality high power beam. Details of the power measurements and collector observations will be presented. Work supported by the US DOE under DE-FC02-04ER54698.

  7. Performance of direct absorption solar collector with nanofluid mixture

    International Nuclear Information System (INIS)

    Turkyilmazoglu, Mustafa

    2016-01-01

    Highlights: • Neat approximations for temperature and solar collector efficiency are presented. • The non-adiabatic and isothermal base mechanisms optimize the surface absorption. • Heat transferring material at the bottom panel enhances the thermal efficiency. • Isothermal base panel leads to maximum thermal efficiency of the solar receiver. - Abstract: The enhancement of performance by increasing the thermal efficiency of a direct absorption solar collector based on an alumina–water nanofluid is the prime target of the present research. The base panel of the collector channel is subject to either a non adiabatic or an isothermal wall condition both of which introduce two new physical parameters. Analytical solutions for the temperature field are worked out in both cases for a two dimensional steady-state model recently outlined in the literature. The desired increase in the temperature of the heat transferring nanofluid is achieved either by slightly rising the heat transfer coefficient of the bottom panel coating or by prescribing a bottom surface temperature. As a consequence of the increase in the final outlet mean temperature, the solar collector thermal efficiency is found to be enhanced via increasing the new physical parameters as compared to the traditional adiabatic wall case. For instance, 85.63% thermal efficiency of solar collector is achievable for non adiabatic bottom panel by adding suspended aluminum nanoparticles into the pure water. Even better than this, considering isothermal base panels, 100% efficiency is attained more rapidly with lesser base temperatures in the presence of higher nanoparticle volume fractions.

  8. Effect of the collector tube profile on Pitot pump performances

    Science.gov (United States)

    Komaki, K.; Kanemoto, T.; Sagara, K.; Umekage, T.

    2013-12-01

    The pitot pump is composed of the rotating casing with the impeller channel and the pitot tube type collector as the discharge line. The radial impeller feeds water to the rotating casing. The water rotating together with the casing is caught by the stationary pitot tube type collector, and then discharges to the outside. This type pump, as the extra high head pump, is provided mainly for boiler feed systems, and has been designed by trial and error. To optimize the pump profiles, it is desirable to investigate not only performances but also internal flow conditions. This paper discusses experimentally and numerically the relation between the pump performances and the flow conditions in the rotating casing. The moderately larger dimensions of the collector make the pump head and the discharge high with the higher hydraulic efficiency. The flow in the casing is almost the forced vortex type whose velocity is in proportion to the radius but the core velocity is affected with the drag force of the stationary collector. Based upon the above results, the profile of the pitot tube type collector was optimized with the numerical simulation.

  9. Effect of the collector tube profile on Pitot pump performances

    International Nuclear Information System (INIS)

    Komaki, K; Sagara, K; Kanemoto, T; Umekage, T

    2013-01-01

    The pitot pump is composed of the rotating casing with the impeller channel and the pitot tube type collector as the discharge line. The radial impeller feeds water to the rotating casing. The water rotating together with the casing is caught by the stationary pitot tube type collector, and then discharges to the outside. This type pump, as the extra high head pump, is provided mainly for boiler feed systems, and has been designed by trial and error. To optimize the pump profiles, it is desirable to investigate not only performances but also internal flow conditions. This paper discusses experimentally and numerically the relation between the pump performances and the flow conditions in the rotating casing. The moderately larger dimensions of the collector make the pump head and the discharge high with the higher hydraulic efficiency. The flow in the casing is almost the forced vortex type whose velocity is in proportion to the radius but the core velocity is affected with the drag force of the stationary collector. Based upon the above results, the profile of the pitot tube type collector was optimized with the numerical simulation

  10. Solar collectors and heat pump: Market review and preliminary simulation results

    International Nuclear Information System (INIS)

    Tepe, Rainer; Roennelid, Mats

    2002-01-01

    Heating systems that combine solar collectors and a heat pump available on the market in Sweden have been studied. A majority of the systems found combine the solar collectors with a ground source heat pump. The technology for combining the collectors and the heat pump does however vary considerably. In the most simple systems, the collectors heat the return water from the heat pump, i.e. the collectors are used for raising the temperature in the boreholes for the heat pump. In the advanced systems, the solar heat is used for tap water, space heating and for raising the temperature of the heat pump's evaporator. There exist only very few comparative evaluations of the contributions from solar collectors in heat pump systems, and there is a need for finding the potential for this technique. In the present study, results are reported from preliminary simulations of solar collectors and ground source heat pumps installed in one-family houses. Simulations are made for two heating loads: 8,650 and 16,500 kWh/year resp., and a hot water load of 3,000 kWh/year. The study shows that: the temperature of the borehole decreases when solar collectors are not used (about 1.2 deg C in three years): 8 m 2 glazed solar collectors used for hot water production can reduce the electricity consumption with up to 13%, with best results in the house with low heating load: 50 m 2 unglazed solar collectors coupled to the evaporator or the borehole can give reductions of up to 14%, largest reduction in the house with high heating load, where the heat extraction from the borehole is large: the unglazed collectors have the highest economic potential, and can be cost effective for houses with high heating load: the simulations do not include a thorough system optimization, better results can be expected from continued optimization work

  11. Performance of evaporator-collector and air collector in solar assisted heat pump dryer

    International Nuclear Information System (INIS)

    Hawlader, M.N.A.; Rahman, S.M.A.; Jahangeer, K.A.

    2008-01-01

    A solar assisted heat pump dryer has been designed, fabricated and tested. This paper presents the performance of the evaporator-collector and the air collector when operated under the same meteorological conditions. ASHRAE standard procedure for collector testing has been followed. The evaporator-collector of the heat pump is acting directly as the solar collector, and the temperature of the refrigerant at the inlet to the evaporator-collector always remained below the ambient temperature. Because of the rejection of sensible and latent heats of air at the dehumidifier, the temperature at the inlet to the air collector is lower than that of the ambient air. Hence, the thermal efficiency of the air collector also increases due to a reduction of losses from the collector. The efficiencies of the evaporator-collector and the air collector were found to vary between 0.8-0.86 and 0.7-0.75, respectively, when operated under the meteorological conditions of Singapore

  12. Development of a selective surface vacuum collector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    de Waal, H.; Simonis, F.

    1980-01-01

    To make solar energy useful for cooling applications a flat plate high performance collector, which can supply solar energy at 100 to 150/sup 0/C, has been developed. To achieve a reasonable efficiency at these temperatures the thermal heat loss must be very small. This has been obtained by (1) concentration of sunlight (c = 1.6); (2) evacuation of the collector housing to eliminate convection currents (pressure less than or equal to 4kPa); (3) spectral selective coating on the absorber; and (4) a low conductive gas in the collector housing (pressure approx. = 2kPa). The collector consists of a metal box with a glass cover hermetically sealed to it in the way double glazing units are manufactured. The sides of the V-trough concentrators support the glass cover. Measurements have been performed concerning heat loss factor and durability of the vacuum. The first prototype, fitted with a spectral selective coating of tin-oxide on enameled steel (epsilon = 0.25) showed a heat-loss of 2.0 W/m/sup 2/ /sup 0/C at 90/sup 0/C, being in reasonable agreement with calculations. Improvements with respect to the spectral selective coating and the use of a low conductive gas are necessary and will lead to a heat loss factor of about 1 W/m/sup 2/ /sup 0/C. Measurements have shown that in the chosen system the desired vacuum level can be maintained for at least 10 to 15 years.

  13. Thermal-hydraulic analysis under partial loss of flow accident hypothesis of a plate-type fuel surrounded by two water channels using RELAP5 code

    OpenAIRE

    Itamar Iliuk; José Manoel Balthazar; Ângelo Marcelo Tusset; José Roberto Castilho Piqueira

    2016-01-01

    Thermal-hydraulic analysis of plate-type fuel has great importance to the establishment of safety criteria, also to the licensing of the future nuclear reactor with the objective of propelling the Brazilian nuclear submarine. In this work, an analysis of a single plate-type fuel surrounding by two water channels was performed using the RELAP5 thermal-hydraulic code. To realize the simulations, a plate-type fuel with the meat of uranium dioxide sandwiched between two Zircaloy-4 plates was prop...

  14. Solar light (hv) and H2O2/hv photo-disinfection of natural alkaline water (pH 8.6) in a compound parabolic collector at different day periods in Sahelian region.

    Science.gov (United States)

    Ndounla, J; Pulgarin, C

    2015-11-01

    The photo-disinfection of natural alkaline surface water (pH 8.6 ± 0.3) for drinking purposes was carried out under solar radiation treatments. The enteric bacteria studied were the wild total coliforms/Escherichia coli (10(4) CFU/ml) and Salmonella spp. (10(4) CFU/ml) naturally present in the water. The photo-disinfection of a 25-l water sample was carried out in a solar compound parabolic collector (CPC) in the absence and in the presence of hydrogen peroxide (H2O2). The addition of H2O2 (10 mg/L) to the sample water was sufficient to enhance the photo-disinfection and ensure an irreversible lethal action on the wild enteric bacteria contents of the sample. The inactivation kinetic of the system was significantly enhanced compared to the one carried out without H2O2 addition. The effect of the solar radiation parameters on the efficiency of the photo-disinfection were assessed. The pH has increased during the treatment in all the photo-disinfection processes (hv and H2O2/hv). The Salmonella spp strain has shown the best effective inactivate time in alkaline water than the one recorded under acidic or near-neutral conditions. The evolution of some physico-chemical parameters of the water (turbidity, NO2(-), NO3(-), NH4(+), HPO4(2-), and bicarbonate (HCO3(-))) was monitored during the treatment. Finally, the possible mechanistic process involved during the enteric bacteria inactivation was suggested.

  15. Solar pre-heating of water for steam generation in the friendship textile mill

    International Nuclear Information System (INIS)

    Sid -Ahmed, M.O.; Hussien, T.

    1994-01-01

    The technology of solar water heating is simple and can be used for pre-heating of water entering a boiler. In this paper the economics of solar pre-heating of water was calculated. The calculations were based on the performance and cost of a locally-made flat plate collector, and the performance and fuel consumption of a boiler in a textile mill. The results showed that a collector area of about 800 meter square with initial cost of about LS 5,000,000, could save annually about 130 tons of furnace oil. ( Author )

  16. Installation package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    The concentrating solar collector panels comprise a complete package array consisting of collector panels using modified Fresnel prismatic lenses for a 10 to 1 concentrating ratio, supporting framework, fluid manifolding and tracking drive system, and unassembled components for field erection.

  17. Optimized concentrating/passive tracking solar collector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sterne, K E; Johnson, A L; Grotheer, R H

    1979-01-01

    A concentrating solar collector having about half the material cost of other collectors with similar performance is described. The selected design is a Compound Parabolic Concentrator (CPC) which concentrates solar energy throughout the year without requiring realignment. Output is a fluid heated to 100/sup 0/C with good efficiency. The optical design of the reflector surface was optimized, yielding a 2.0:1 concentration ratio with a 60/sup 0/C acceptance angle and a low profile. Double glazing was chosen consisting of a polyester film outer glazing and an inner glazing of glass tubes around the absorbers. The selectively coated steel absorber tubes are connected in series with flexible plastic tubing. Much development effort went into the materials for the reflector subassembly. A laminate of metalized plastic film over plaster was chosen for the reflective surface. The reflector is rigidized by attaching filled epoxy header plates at each end. Aluminum side rails and an insulating back complete the structure. The finished design resulted in a material cost of $21.40 per square meter in production quantities. Performance testing of a prototype produced a 50% initial efficiency rating. This is somewhat lower than expected, and is due to materials and processes used in the prototype for the outer glazing, reflective surface and absorber coating. However, the efficiency curve drops only slightly with increasing temperature differential, showing the inherent advantage of the concentrator over flat plate collectors.

  18. Synergetic effect of copper-plating wastewater as a catalyst for the destruction of acrylonitrile wastewater in supercritical water oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Young Ho; Lee, Hong-shik; Lee, Young-Ho [School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Kim, Jaehoon; Kim, Jae-Duck [Supercritical Fluid Research Laboratory, Energy and Environment Research Division, Korea Institute of Science and Technology (KIST), 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Lee, Youn-Woo, E-mail: ywlee@snu.ac.kr [School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2009-08-15

    A new supercritical water oxidation process for the simultaneous treatment of mixed wastewater containing wastewater from acrylonitrile manufacturing processes and copper-plating processes was investigated using a continuous tubular reactor system. Experiments were carried out at temperatures ranging from 400 to 600 deg. C and a pressure of 25 MPa. The residence time was fixed at 2 s by changing the flow rates of feeds, depending on reaction temperature. The initial total organic carbon (TOC) concentration of the wastewaters and the O{sub 2} concentration at the reactor inlet were kept constant at 0.49 and 0.74 mol/L. It was confirmed that the copper-plating wastewater accelerated the TOC conversion of acrylonitrile wastewater from 17.6% to 67.3% at a temperature of 450 deg. C. Moreover, copper and copper oxide nanoparticles were generated in the process of supercritical water oxidation (SCWO) of mixed wastewater. 99.8% of copper in mixed wastewater was recovered as solid copper and copper oxides at a temperature of 600 deg. C, with their average sizes ranging from 150 to 160 nm. Our study showed that SCWO provides a synergetic effect for simultaneous treatment of acrylonitrile and copper-plating wastewater. During the reaction, the oxidation rate of acrylonitrile wastewater was enhanced due to the in situ formation of nano-catalysts of copper and/or copper oxides, while the exothermic decomposition of acrylonitrile wastewater supplied enough heat for the recovery of solid copper and copper oxides from copper-plating wastewater. The synergetic effect of wastewater treatment by the newly proposed SCWO process leads to full TOC conversion, color removal, detoxification, and odor elimination, as well as full recovery of copper.

  19. Heat transfer characteristics in the channel of a finned absorber solar collector; Caracteristicas da transferencia de calor no canal de um coletor solar de absorvedor aletado

    Energy Technology Data Exchange (ETDEWEB)

    Saboya, Sergio Mourao [Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil). Inst. Tecnologico de Aeronautica; Saboya, Francisco Eduardo Mourao [Universidade Federal Fluminense, Niteroi, RJ (Brazil)]. E-mails: saboya@mec.ita.cta.br; fsaboya@mec.uff.br

    2000-07-01

    Finned absorber solar collectors are devices in which plates (fins) are fixed perpendicularly to the absorber plate. The purpose of these fins is to cause the so called 'cavity effect', lowering the collector losses. This paper studies the heat transfer that occurs in the collector channel. This analysis is done using the efficiency of the collector, which is calculated solving the system of equations that govern the collector thermal behavior, and the computation of the convection heat transfer between the fluid flowing in the channel and the absorber plate. This analysis allows the calculation of design parameters such as mass flow rate and exit bulk temperature of the fluid. (author)

  20. Thermal-hydraulic analysis under partial loss of flow accident hypothesis of a plate-type fuel surrounded by two water channels using RELAP5 code

    Directory of Open Access Journals (Sweden)

    Itamar Iliuk

    2016-01-01

    Full Text Available Thermal-hydraulic analysis of plate-type fuel has great importance to the establishment of safety criteria, also to the licensing of the future nuclear reactor with the objective of propelling the Brazilian nuclear submarine. In this work, an analysis of a single plate-type fuel surrounding by two water channels was performed using the RELAP5 thermal-hydraulic code. To realize the simulations, a plate-type fuel with the meat of uranium dioxide sandwiched between two Zircaloy-4 plates was proposed. A partial loss of flow accident was simulated to show the behavior of the model under this type of accident. The results show that the critical heat flux was detected in the central region along the axial direction of the plate when the right water channel was blocked.

  1. Modeling the photocatalytic mineralization in water of commercial formulation of estrogens 17-β estradiol (E2) and nomegestrol acetate in contraceptive pills in a solar powered compound parabolic collector.

    Science.gov (United States)

    Colina-Márquez, José; Machuca-Martínez, Fiderman; Li Puma, Gianluca

    2015-07-22

    Endocrine disruptors in water are contaminants of emerging concern due to the potential risks they pose to the environment and to the aquatic ecosystems. In this study, a solar photocatalytic treatment process in a pilot-scale compound parabolic collector (CPC) was used to remove commercial estradiol formulations (17-β estradiol and nomegestrol acetate) from water. Photolysis alone degraded up to 50% of estradiol and removed 11% of the total organic carbon (TOC). In contrast, solar photocatalysis degraded up to 57% of estrogens and the TOC removal was 31%, with 0.6 g/L of catalyst load (TiO2 Aeroxide P-25) and 213.6 ppm of TOC as initial concentration of the commercial estradiols formulation. The adsorption of estrogens over the catalyst was insignificant and was modeled by the Langmuir isotherm. The TOC removal via photocatalysis in the photoreactor was modeled considering the reactor fluid-dynamics, the radiation field, the estrogens mass balance, and a modified Langmuir-Hinshelwood rate law, that was expressed in terms of the rate of photon adsorption. The optimum removal of the estrogens and TOC was achieved at a catalyst concentration of 0.4 g/L in 29 mm diameter tubular CPC reactors which approached the optimum catalyst concentration and optical thickness determined from the modeling of the absorption of solar radiation in the CPC, by the six-flux absorption-scattering model (SFM).

  2. Modeling the Photocatalytic Mineralization in Water of Commercial Formulation of Estrogens 17-β Estradiol (E2 and Nomegestrol Acetate in Contraceptive Pills in a Solar Powered Compound Parabolic Collector

    Directory of Open Access Journals (Sweden)

    José Colina-Márquez

    2015-07-01

    Full Text Available Endocrine disruptors in water are contaminants of emerging concern due to the potential risks they pose to the environment and to the aquatic ecosystems. In this study, a solar photocatalytic treatment process in a pilot-scale compound parabolic collector (CPC was used to remove commercial estradiol formulations (17-β estradiol and nomegestrol acetate from water. Photolysis alone degraded up to 50% of estradiol and removed 11% of the total organic carbon (TOC. In contrast, solar photocatalysis degraded up to 57% of estrogens and the TOC removal was 31%, with 0.6 g/L of catalyst load (TiO2 Aeroxide P-25 and 213.6 ppm of TOC as initial concentration of the commercial estradiols formulation. The adsorption of estrogens over the catalyst was insignificant and was modeled by the Langmuir isotherm. The TOC removal via photocatalysis in the photoreactor was modeled considering the reactor fluid-dynamics, the radiation field, the estrogens mass balance, and a modified Langmuir–Hinshelwood rate law, that was expressed in terms of the rate of photon adsorption. The optimum removal of the estrogens and TOC was achieved at a catalyst concentration of 0.4 g/L in 29 mm diameter tubular CPC reactors which approached the optimum catalyst concentration and optical thickness determined from the modeling of the absorption of solar radiation in the CPC, by the six-flux absorption-scattering model (SFM.

  3. Solar collectors for swimming pools still going strong

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    According to the opinion of the experts, solar energy heating may be technically 'mature' but the profitability is by no means that far. However, solar systems are a good alternative for heating the water in swimming pools. Four solar collector systems developed by different firms to heat swimming pools, including prices, are presented.

  4. Investigations on efficiencies of HT solar collectors for different flow rates and collector tilts

    DEFF Research Database (Denmark)

    Chen, Ziqian; Perers, Bengt; Furbo, Simon

    2013-01-01

    Two HT solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one solar collector is equipped with an ETFE foil between the abso......Two HT solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one solar collector is equipped with an ETFE foil between...... the absorber and the cover glass and the other is without ETFE foil. The efficiencies for the collectors are tested at different flow rates and tilt. On the basis of the measured efficiencies, the efficiencies for the collectors as functions of flow rates are obtained. The calculated efficiencies are in good...

  5. Thermal advantage of tracking solar collectors under Danish weather conditions

    DEFF Research Database (Denmark)

    Andersen, Elsa; Dragsted, Janne; Furbo, Simon

    2010-01-01

    Theoretical investigations have been carried out with the aim to elucidate the thermal advantage of tracking solar collectors for different weather conditions in Kgs. Lyngby, Denmark (55.8°N), and for the weather conditions in Sisimiut, Greenland (66.9°N), just north of the arctic circle....... The investigations are based on calculations with a newly developed program. Measured weather data from a solar radiation measurement station at Technical University of Denmark in Kgs. Lyngby Denmark in the period 1990 to 2002 and the Danish Design Reference Year, DRY data file are used in the investigations....... The weather data used for Sisimiut are based on a Test Reference Year, TRY weather data file. The thermal advantages of different tracking strategies is investigated for two flat plate solar collectors with different efficiencies, operated at different temperature levels. The investigations show...

  6. Development of a Solar Assisted Drying System Using Double-Pass Solar Collector with Finned Absorber

    Science.gov (United States)

    Azmi, M. S. M.; Othman, M. Y.; Sopian, K.; Ruslan, M. H.; Majid, Z. A. A.; Fudholi, A.; Yasin, J. M.

    2012-09-01

    The Solar Energy Research Group, Universiti Kebangsaan Malaysia, International Islamic University Malaysia and Yayasan FELDA has designed and constructed a solar assisted drying system at OPF FELDA Factory, Felda Bukit Sagu 2, Kuantan, Pahang. The drying system has a total of six double-pass solar collectors. Each collector has a length of 480 cm and a width of 120 cm. The first channel depth is 3.5 cm and the second channel depth is 7 cm. Longitudinal fins made of angle aluminium, 0.8 mm thickness were attached to the bottom surface of the absorber plate. The solar collectors are arranged as two banks of three collectors each in series. Internal manifold are used to connect the collectors. Air enters through the first channel and then through the second channel of the collector. An auxiliary heater source is installed to supply heat under unfavourable solar radiation condition. An on/off controller is used to control the startup and shutdown of the auxiliary heater. An outlet temperature of 70-75 °C can be achieved at solar radiation range of 800-900 W/m2 and flow rate of 0.12 kg/s. The average thermal efficiency of a solar collector is approximately 37%.

  7. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    Science.gov (United States)

    Tecimer, M.; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J.

    2001-12-01

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 π mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design.

  8. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    Energy Technology Data Exchange (ETDEWEB)

    Tecimer, M. E-mail: tecimer@post.tau.ac.il; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J

    2001-12-21

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 {pi} mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design.

  9. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    International Nuclear Information System (INIS)

    Tecimer, M.; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J.

    2001-01-01

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 π mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design

  10. Development of a Solar Assisted Drying System Using Double-Pass Solar Collector with Finned Absorber

    International Nuclear Information System (INIS)

    Azmi, M S M; Sopian, K; Ruslan, M H; Fudholi, A; Majid, Z A A; Yasin, J M; Othman, M Y

    2012-01-01

    The Solar Energy Research Group, Universiti Kebangsaan Malaysia, International Islamic University Malaysia and Yayasan FELDA has designed and constructed a solar assisted drying system at OPF FELDA Factory, Felda Bukit Sagu 2, Kuantan, Pahang. The drying system has a total of six double-pass solar collectors. Each collector has a length of 480 cm and a width of 120 cm. The first channel depth is 3.5 cm and the second channel depth is 7 cm. Longitudinal fins made of angle aluminium, 0.8 mm thickness were attached to the bottom surface of the absorber plate. The solar collectors are arranged as two banks of three collectors each in series. Internal manifold are used to connect the collectors. Air enters through the first channel and then through the second channel of the collector. An auxiliary heater source is installed to supply heat under unfavourable solar radiation condition. An on/off controller is used to control the startup and shutdown of the auxiliary heater. An outlet temperature of 70–75 °C can be achieved at solar radiation range of 800–900 W/m 2 and flow rate of 0.12 kg/s. The average thermal efficiency of a solar collector is approximately 37%.

  11. A comparison of two cloudwater/fogwater collectors: The rotating arm collector and the caltech active strand cloudwater collector

    Science.gov (United States)

    Collett, Jeffrey L.; Daube, Bruce C.; Munger, J. William; Hoffmann, Michael R.

    A side-by-side comparison of the Rotating Arm Collector (RAC) and the Caltech Active Strand Cloudwater Collector (CASCC) was conducted at an elevated coastal site near the eastern end of the Santa Barbara Channel in southern California. The CASCC was observed to collect cloudwater at rates of up to 8.5 ml min -1. The ratio of cloudwater collection rates was found to be close to the theoretical prediction of 4.2:1 (CASCC:RAC) over a wide range of liquid water contents (LWC). At low LWC, however, this ratio climbed rapidly, possibly reflecting a predominance of small droplets under these conditions, coupled with a greater collection efficiency of small droplets by the CASCC. Cloudwater samples collected by the RAC had significantly higher concentrations of Na +, Ca 2+, Mg 2+ and Cl - than those collected by the CASCC. These higher concentrations may be due to differences in the chemical composition of large vs small droplets. No significant differences were observed in concentrations of NO 3-, SO 42- or NH 4+ in samples collected by the two instruments.

  12. Modification of the Hottel-Whillier-Bliss equation for cover absorption effects in solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Wijeysundera, N E

    1981-01-01

    The effects of solar radiation absorption and the thermal resistance of a solar collector cover system on the various factors which occur in the Hottel-Whillier-Bliss (HWB) equation are considered. It is shown that by extending the thermal network analogy to systems with distributed heat sources, the heat transfer analysis of the collector can be done with little computational effort. The analysis also leads to a simple form of the HWB equation, with additional factors to account for the source distribution and the thermal resistance of the cover system, and it is applicable to conventional flat plate collectors and to other thermal trap collectors. A series of calculations for multilayer systems is presented to show the relative importance of the various factors in the modified HWB equation for different cover configurations.

  13. A Series of Supramolecular Complexes for Solar Energy Conversion via Water Reduction to Produce Hydrogen: An Excited State Kinetic Analysis of Ru(II,Rh(III,Ru(II Photoinitiated Electron Collectors

    Directory of Open Access Journals (Sweden)

    Shamindri M. Arachchige

    2011-12-01

    Full Text Available Mixed-metal supramolecular complexes have been designed that photochemically absorb solar light, undergo photoinitiated electron collection and reduce water to produce hydrogen fuel using low energy visible light. This manuscript describes these systems with an analysis of the photophysics of a series of six supramolecular complexes, [{(TL2Ru(dpp}2RhX2](PF65 with TL = bpy, phen or Ph2phen with X = Cl or Br. The process of light conversion to a fuel requires a system to perform a number of complicated steps including the absorption of light, the generation of charge separation on a molecular level, the reduction by one and then two electrons and the interaction with the water substrate to produce hydrogen. The manuscript explores the rate of intramolecular electron transfer, rate of quenching of the supramolecules by the DMA electron donor, rate of reduction of the complex by DMA from the 3MLCT excited state, as well as overall rate of reduction of the complex via visible light excitation. Probing a series of complexes in detail exploring the variation of rates of important reactions as a function of sub-unit modification provides insight into the role of each process in the overall efficiency of water reduction to produce hydrogen. The kinetic analysis shows that the complexes display different rates of excited state reactions that vary with TL and halide. The role of the MLCT excited state is elucidated by this kinetic study which shows that the 3MLCT state and not the 3MMCT is likely that key contributor to the photoreduction of these complexes. The kinetic analysis of the excited state dynamics and reactions of the complexes are important as this class of supramolecules behaves as photoinitiated electron collectors and photocatalysts for the reduction of water to hydrogen.

  14. Antibiotic resistance in triclosan heterotrophic plate count bacteria from sewage water / Ilsé Coetzee

    OpenAIRE

    Coetzee, Ilsé

    2015-01-01

    The concentration of triclosan in antiseptics, disinfectants and preservatives in products exceeds the minimal lethal levels. Extensive use of triclosan and antibiotics results in bacterial resistance to their active ingredients. The precise relationship between use and resistance, however, has been challenging to define. The aim of the study was to identify and determine antibiotic resistance profiles of triclosan tolerant heterotrophic plate count bacteria isolates from sewag...

  15. Analysis of WWER 1000 collector cracking mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Matocha, K.; Wozniak, J. [Vitkovice J.S.C., Ostrava (Switzerland)

    1997-12-31

    The presentation reviews the large experimental program, started in 1993 in Vitkovice, where the main aim was: (1) a detailed study of strain and thermal ageing, dissolved oxygen content and temperature on subcritical crack growth in 10NiMo8.5 (10GN2MFA) steel, (2) a detailed study of the effect of high temperature water and tube expansion technology on fracture behaviour of ligaments between holes for heat exchange tubes, and (3) a detailed study of the effect of drilling, tube expansion technology and heat treatment on residual stresses on the surface of holes for heat exchange tubes. The aim of all these investigations was to find a dominant damage mechanism responsible for collector cracking to be able to judge the efficiency of implemented modifications and suggested countermeasures and to answer a very important question whether proper operation conditions (mainly water chemistry) make the operation of steam generators made in Vitcovice safe throughout the planned lifetime. 10 refs.

  16. Analysis of WWER 1000 collector cracking mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Matocha, K; Wozniak, J [Vitkovice J.S.C., Ostrava (Switzerland)

    1998-12-31

    The presentation reviews the large experimental program, started in 1993 in Vitkovice, where the main aim was: (1) a detailed study of strain and thermal ageing, dissolved oxygen content and temperature on subcritical crack growth in 10NiMo8.5 (10GN2MFA) steel, (2) a detailed study of the effect of high temperature water and tube expansion technology on fracture behaviour of ligaments between holes for heat exchange tubes, and (3) a detailed study of the effect of drilling, tube expansion technology and heat treatment on residual stresses on the surface of holes for heat exchange tubes. The aim of all these investigations was to find a dominant damage mechanism responsible for collector cracking to be able to judge the efficiency of implemented modifications and suggested countermeasures and to answer a very important question whether proper operation conditions (mainly water chemistry) make the operation of steam generators made in Vitcovice safe throughout the planned lifetime. 10 refs.

  17. Characteristics of evacuated tubular solar thermal collector as input energy for cooling system at Universitas Indonesia

    Science.gov (United States)

    Alhamid, M. Idrus; Nasruddin, Aisyah, Nyayu; Sholahudin

    2017-03-01

    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%.

  18. Solar Water Heating as a Potential Source for Inland Norway Energy Mix

    Directory of Open Access Journals (Sweden)

    Dejene Assefa Hagos

    2014-01-01

    Full Text Available The aim of this paper is to assess solar potential and investigate the possibility of using solar water heating for residential application in Inland Norway. Solar potential based on observation and satellite-derived data for four typical populous locations has been assessed and used to estimate energy yield using two types of solar collectors for a technoeconomic performance comparison. Based on the results, solar energy use for water heating is competitive and viable even in low solar potential areas. In this study it was shown that a typical tubular collector in Inland Norway could supply 62% of annual water heating energy demand for a single residential household, while glazed flat plates of the same size were able to supply 48%. For a given energy demand in Inland Norway, tubular collectors are preferred to flat plate collectors for performance and cost reasons. This was shown by break-even capital cost for a series of collector specifications. Deployment of solar water heating in all detached dwellings in Inland could have the potential to save 182 GWh of electrical energy, equivalent to a reduction of 15,690 tonnes of oil energy and 48.6 ktCO2 emissions, and contributes greatly to Norway 67.5% renewable share target by 2020.

  19. Economic analysis of flat plate collectors of solar energy

    International Nuclear Information System (INIS)

    Ozsabuncuoglu, I.H.

    1995-01-01

    Although solar energy potential in Turkey is far more than its total annual energy consumption, because of technical, economic and efficiency problems it cannot be harnessed to its fullest extent. Solar energy collecting systems have an initial cost two to five times higher than alternatives using electricity, LPG, fuel or other solid energy sources. However, their annual repair and maintenance costs are much lower than alternatives due to high energy prices. Solar systems with inflated annual costs have a minimum present value of US$867.19. Solar energy systems can be recommended for the countries that want a dependable and environmentally sound energy source. However, investment in R and D activities is necessary to reduce total cost of the system through improved efficiency and better production technology. (author)

  20. Protecting solar collector systems from corrosion

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    The main cause of the reduced life of a solar heating system is corrosion of the exterior parts and the internal components. This report outlines ways of reducing the cost of solar heating by reducing the corrosion in solar heating systems, and hence increasing the system's service life. Mechanisms for corrosion are discussed: these include galvanic corrosion and crevice corrosion. Means of minimizing corrosion at the design stage are then described. Such methods, when designing the solar collector, involve ensuring proper drainage of exterior water; eliminating situations where moisture, dirt and pollutants may collect; preventing condensation inside the collector; using proper gaskets and sealants at appropriate places; and selecting optimum materials and coatings. Interior corrosion can be minimized at the design stage by choosing a good heat transfer fluid and corrosion inhibitor, in the case of systems where liquids are used; ensuring a low enough flow rate to avoid erosion; designing the system to avoid crevices; and avoiding situations where galvanic corrosion could occur. Other procedures are given for minimizing corrosion in the construction and operation of solar heating systems. 7 figs., 7 tabs.

  1. Collector ring project at FAIR

    International Nuclear Information System (INIS)

    Dolinskii, A; Blell, U; Dimopoulou, C; Gorda, O; Leibrock, H; Litvinov, S; Laier, U; Schurig, I; Weinrich, U; Berkaev, D; Koop, I; Starostenko, A; Shatunov, P

    2015-01-01

    The collector ring is a dedicated ring for fast cooling of ions coming from separators at the FAIR project. To accommodate optimal technical solutions, a structure of a magnet lattice was recently reviewed and modified. Consequently, more appropriate technical solutions for the main magnets could be adopted. A general layout and design of the present machine is shown. The demanding extraction schemes have been detailed and open design issues were completed. (paper)

  2. Solar space and water heating system installed at Charlottesville, Virginia

    Science.gov (United States)

    1980-01-01

    The solar energy system located at David C. Wilson Neuropsychiatric Hospital, Charlottesville, Virginia, is described. The solar energy system consists of 88 single glazed, Sunworks 'Solector' copper base plate collector modules, hot water coils in the hot air ducts, a Domestic Hot Water (DHW) preheat tank, a 3,000 gallon concrete urethane insulated storage tank and other miscellaneous components. Extracts from the site files, specifications, drawings, installation, operation and maintenance instructions are included.

  3. Multiple-effect diffusion solar still coupled with a vacuum-tube collector and heat pipe

    KAUST Repository

    Chong, Tze-Ling; Huang, Bin-Juine; Wu, Po-Hsien; Kao, Yeong-Chuan

    2014-01-01

    The present study develops a multiple-effect diffusion solar still (MEDS) with a bended-plate design in multiple-effect diffusion unit (MDU) to solve the peel-off problem of wick material. The MDU is coupled with a vacuum-tube solar collector

  4. Liquid metal current collectors for high-speed rotating machinery

    International Nuclear Information System (INIS)

    Carr, S.L.

    1976-01-01

    Recent interest in superconducting motors and generators has created a renewed interest in homopolar machinery. Homopolar machine designs have always been limited by the need for compact, high-current, low-voltage, sliding electrical curent collectors. Conventional graphite-based solid brushes are inadequate for use in homopolar machines. Liquid metals, under certain conditions of relative sliding velocities, electrical currents, and magnetic fields are known to be capable of performing well in homopolar machines. An effort to explore the capabilities and limits of a tongue-and-groove style current collector, utilizing sodium-potassium eutectic alloy (NaK) as the working fluid in high sliding speed operation is reported here. A double current collector generator model with a 14.5-cm maximum rotor diameter, 20,000 rpm rotational capability, and electrical current carrying ability was constructed and operated successfully at a peripheral velocity of 125 m/s. The limiting factor in these experiments was a high-speed fluid-flow instability resulting in the ejection of the working fluid from the operating portions of the collectors. The effects of collector size and geometry, working fluid (NaK or water), and cover gas pressure are reported. Hydrodynamic frictional torque-speed curves are given for the two fluids and for several geometries. Electrical resistances as a function of peripheral velocity at 60 amperes are reported, and the phenomenology of the high-speed fluid-flow instabilities is discussed. The possibility of long-term high-speed operation of current collectors of the tongue-and-groove type, along with experimental and theoretical hydrodynamic friction losses at high peripheral velocities, is considered

  5. Measurement of tritium activity in the aluminum pipe of JRR-2 heavy water primary cooling system using imaging plate

    International Nuclear Information System (INIS)

    Motoishi, Shoji; Kobayashi, Katsutoshi

    2000-12-01

    JRR-2 is the heavy water cooling type nuclear reactor, which has been operated for 36 years (1960-1976) and in the process of decommissioning at present. For this reason, evaluation of tritium quantity permeated into the pipe and apparatus of the primary coolant heavy water circulating system is important. In the Radioisotope Production Division, activity of tritium in aluminum pipe was measured with imaging plate (IP), liquid scintillation analyzer and high purity germanium detector (HPGe). After acrylic paints was applied for the region except for tritium contamination on the surface of aluminum pipe, only the oxidized contaminated part was dissolved by 1.5%(1.21M) HF for 3 minutes, and measured with IP. As a result, the tritium was found to permeate in the depth of 25 μm. Moreover, 90% of it was found to be distributed within 7 μm. (author)

  6. Unsteady free convection flow past a semi-infinite vertical plate with constant heat flux in water based nanofluids

    Science.gov (United States)

    Narahari, Marneni

    2018-04-01

    The unsteady free convective flow of nanofluids past a semi-infinite vertical plate with uniform heat flux has been investigated numerically. An implicit finite difference technique of Crank-Nicolson scheme has been employed to solve the governing partial differential equations. Five different types of water based nanofluids containing Cu, Ag, Al2O3, CuO and TiO2 nanoparticles are considered to study the fluid flow characteristics with various time and solid volume fraction parameters. It is found that the local as well as the average Nusselt number for nanofluids is higher than the pure fluid (water). The local skin-friction is higher for pure fluid as compared to the nanofluids. The present numerical results obtained for local Nusselt number are validated with the previously published correlation results for a limiting case and it is found that the results are in good agreement.

  7. Study of thermohydraulic characteristics of upgraded feedwater collector in PGV-440 steam generator

    Energy Technology Data Exchange (ETDEWEB)

    Tarankov, G.A.; Trunov, N.B.; Titov, V.F. [OKB Gidropress (Russian Federation); Urbansky, V.V. [Rovno NPP (Ukraine); Lenkei, I.; Notarosh, M. [Paks NPP (Hungary)

    1995-12-31

    Reconstruction of feedwater distribution collector was performed at unit 1 of Rowno NPP. Main results of measurements of temperatures in water volume, reparation characteristics and impurities distribution are presented. Analysis of tests results and design criteria is given. (orig.).

  8. Study of thermohydraulic characteristics of upgraded feedwater collector in PGV-440 steam generator

    Energy Technology Data Exchange (ETDEWEB)

    Tarankov, G A; Trunov, N B; Titov, V F [OKB Gidropress (Russian Federation); Urbansky, V V [Rovno NPP (Ukraine); Lenkei, I; Notarosh, M [Paks NPP (Hungary)

    1996-12-31

    Reconstruction of feedwater distribution collector was performed at unit 1 of Rowno NPP. Main results of measurements of temperatures in water volume, reparation characteristics and impurities distribution are presented. Analysis of tests results and design criteria is given. (orig.).

  9. Comparison of two temperature control techniques in a forced water heater solar system

    Science.gov (United States)

    Hernández, E.; E Guzmán, R.; Santos, A.; Cordoba, E.

    2017-12-01

    a study on the performance of a forced solar heating system in which a comparative analysis of two control strategies, including the classic on-off control and PID control is presented. From the experimental results it was found that the two control strategies show a similar behaviour in the solar heating system forced an approximate settling time of 60 min and over-elongation 2°C for the two control strategies. Furthermore, the maximum temperature in the storage tank was 46°C and the maximum efficiency of flat plate collector was 76.7% given that this efficiency is the ratio of the energy of the radiation on the collector and the energy used to heat water. The efficiency obtained is a fact well accepted because the business efficiencies of flat plate collectors are approximately 70%.

  10. Real-time ArcGIS and heterotrophic plate count based chloramine disinfectant control in water distribution system.

    Science.gov (United States)

    Bai, Xiaohui; Zhi, Xinghua; Zhu, Huifeng; Meng, Mingqun; Zhang, Mingde

    2015-01-01

    This study investigates the effect of chloramine residual on bacteria growth and regrowth and the relationship between heterotrophic plate counts (HPCs) and the concentration of chloramine residual in the Shanghai drinking water distribution system (DWDS). In this study, models to control HPCs in the water distribution system and consumer taps are also developed. Real-time ArcGIS was applied to show the distribution and changed results of the chloramine residual concentration in the pipe system by using these models. Residual regression analysis was used to get a reasonable range of the threshold values that allows the chloramine residual to efficiently inhibit bacteria growth in the Shanghai DWDS; the threshold values should be between 0.45 and 0.5 mg/L in pipe water and 0.2 and 0.25 mg/L in tap water. The low residual chloramine value (0.05 mg/L) of the Chinese drinking water quality standard may pose a potential health risk for microorganisms that should be improved. Disinfection by-products (DBPs) were detected, but no health risk was identified.

  11. Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1992-01-01

    1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2 · °C). 1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials. 1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2 ·° C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard t...

  12. Thermal performance of evacuated tube heat pipe solar collector

    Science.gov (United States)

    Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

    2016-06-01

    The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

  13. Water curtain

    Energy Technology Data Exchange (ETDEWEB)

    Kutepov, A.I.; Fedotov, I.N.; Prokopov, O.I.

    1982-01-01

    The patented water curtain is used to eliminate gas-oil gushers and is distinguished by the fact that in order to simplify operation, the water-line collector is made out of two symmetrical parts installed with the possibility of relative rotation. The collector is equipped with at least one pipe arranged in the zone of the collector and has openings for the supply of water.

  14. Numerical and experimental investigation of thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Zelzouli, Khaled; Guizani, Amenallah; Kerkeni, Chakib

    2014-01-01

    Highlights: • We studied a thermosyphon solar water heater composed of high-performance components. • A differential equations solution technique is investigated. • The influences of the collector and storage losses on the system performance were examined. • The storage losses have more influence on the long-term performance. - Abstract: A glassed flat plate collector with selective black chrome coated absorber and a low wall conductance horizontal storage are combined in order to set up a high performance thermosyphon system. Each component is tested separately before testing the complete system in spring days. During the test period, effect of different inlet water temperatures on the collector performance is studied and results have shown that the collector can reach a high efficiency and high outlet water temperature even for elevated inlet water temperatures. Subsequently, long term system performance is estimated by using a developed numerical model. The proposed model, accurate and gave a good agreement with experimental results, allowed to describe the heat transfer in the storage. It has shown also that the long-term performances are strongly influenced by losses from the storage than losses from the collector

  15. Electrochemical decomposition of fluorinated wetting agents in plating industry waste water.

    Science.gov (United States)

    Fath, Andreas; Sacher, Frank; McCaskie, John E

    2016-01-01

    Electrochemical decomposition of fluorinated surfactants (PFAS, perfluorinated alkyl substances) used in the plating industry was analyzed and the decomposition process parameters optimized at the laboratory scale and production scale of a 500-liter reactor using lead electrodes. The method and system was successfully demonstrated under production conditions to treat PFAS) with up to 99% efficiency in the concentration range of 1,000-20,000 μg/l (1 ppm-20 ppm). The treatment also reduced hexavalent chromium (Cr(6+)) ions to trivalent chromium (Cr(3+)) ions in the wastewater. If the PFAS-containing wastewater is mixed with other wastewater streams, specifically from nickel plating drag out solution or when pH values >5, the treatment process is ineffective. For the short chain PFAS, (perfluorobutylsulfonate) the process was less efficient than C6-C8 PFAS. The process is automated and has safety procedures and controls to prevent hazards. The PFAS were decomposed to hydrogen fluoride (HF) under the strong acid electrochemical operating conditions. Analytical tests showed no evidence of organic waste products remaining from the process. Conventional alternative PFAS removal systems were tested on the waste streams and compared with each other and with the-E-destruct (electrochemical oxidation) process. For example, ion exchange resin (IX resin) treatment of wastewater to complex and remove PFAS was found to be seven times more efficient when compared to the conventional activated carbon absorption (C-treat) process. However, the E-destruct process is higher in capacity, exhibits longer service life and lower operating costs than either IX or C-treat methods for elimination of PFAS from these electroplating waste streams.

  16. Two non-tracking solar collectors: Design criteria and performance analysis

    International Nuclear Information System (INIS)

    Ratismith, Wattana; Inthongkhum, Anusorn; Briggs, John

    2014-01-01

    Highlights: • A collector module designed to capture solar radiation efficiently is proposed. • Two different compound parabolic trough designs are examined and tested. • A novel design with a flat base trough and vertical absorber operates efficiently in direct and diffuse sunlight. - Abstract: We propose fixed (non-tracking) configurations of solar light collector modules which are designed to operate efficiently throughout the day, i.e. for varying incident angles of direct sunlight, and in conditions of diffuse solar irradiation. We present two trough designs of compound parabolic collector (CPC) type. One, a more conventional double-parabolic trough, has the absorber plate perpendicular to the vertical axis of the trough cross-section. The other, of a new flat-base shape, has the absorber plate parallel. The collectors have two novel features appropriate to non-tracking. The first is a smoothing of the power output over the day by the simple expedient of arranging three troughs tilted at different angles. The second is the original design of the flat-base trough allowing optimal interception of the caustic surfaces of this non-focussing device. By ray-tracing analysis of the different trough shapes and absorber plate orientation, we emphasise the design criteria for achievement of a high intercept factor throughout the day without tracking and demonstrate the superiority of the flat-base collector over the double-parabolic design. In test experiments we show that the high temperatures (≈180 °C) necessary for some industrial process heat applications can be achieved. Also test results of the efficiency of the proposed systems are presented which indicate that the flat-base trough with vertical absorber plate is superior to the double-parabolic trough with horizontal absorber plate

  17. Exergy analysis of photovoltaic solar collector

    International Nuclear Information System (INIS)

    Sopian, K.; Othman, M.Y.Hj.

    1998-01-01

    The exergy analysis (availability or second law analysis) is applied to the photovoltaic thermal solar collector. Photovoltaic thermal collector is a special type of solar collector where electricity and heat are produced simultaneously. The electricity produced from the photovoltaic thermal collector is all converted into useful work. The available quantity of the heat collected can readily be determined by taking into account both the quantity (heat quantity) and quality ( a function of temperature) of the thermal energy. Therefore, using the concept of exergy allows heat produced from the thermal collector and the electricity generated from the photovoltaic cells to be compared or to be evaluated on the basis of a common measure such as the effectiveness on solar energy collection or the total amount of available energy. In this paper, the effectiveness of solar energy collection is called combined photovoltaic thermal exergy efficiency. An experimental setup of a double pas photovoltaic thermal solar collector has been deigned, fabricated and tested. (author)

  18. Evaluation of the potential of optical switching materials for overheating protection of thermal solar collectors - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Huot, G.; Roecker, Ch.; Schueler, A.

    2008-01-15

    Providing renewable energy for domestic hot water production and space heating, thermal solar collectors are more and more widespread, and users' expectations with respect to performance and service lifetime are rising continuously. The durability of solar collector materials is a critical point as the collector lifetime should be at least 25 years. Overheating and the resulting stagnation of the collector is a common problem with solar thermal systems. During stagnation high temperatures lead to water evaporation, glycol degradation, and stresses in the collector with increasing pressure. Special precautions are necessary to release this pressure; only mechanical solutions exist nowadays. Additionally, the occurring elevated temperatures lead to degradation of the materials that compose collectors: seals, insulation materials, and also the selective coating which is the most important part of the collector. A promising way to achieve active cooling of collectors without any mechanical device for pressure release or collector emptying is to produce a selective coating which is able to switch its optical properties at a critical temperature Tc. An optical switch allows changing the selective coating efficiency; the goal is to obtain a coating with a poor selectivity above Tc (decreasing of absorptance, increasing of emittance). Obtaining self-cooling collectors will allow increasing collector surfaces on facades and roofs in order to get high efficiency and hot water production during winter without inconvenient overheating during summer. Optical switching of materials can be obtained by many ways. Inorganic and organic thermochromic compounds, and organic thermotropic coatings are the main types of switching coatings that have been studied at EPFL-LESO-PB. Aging studies of organic thermochromic paints fabricated at EPFL suggest that the durability of organic compounds might not be sufficient for glazed metallic collectors. First samples of inorganic coatings

  19. Residual stress improvement in multi-layer welded plates using water-shower cooling during welding process

    International Nuclear Information System (INIS)

    Yanagida, Nobuyoshi; Koide, Hiroo

    2006-01-01

    To reduce tensile residual stress in a welded region, we developed a new welding method that applies a water-shower behind the welding torch. When this method is applied to welding of austenitic stainless steel plates, cooling conditions mainly determine how much the residual stress can be reduced. To determine the conditions, we first used FEM to evaluate the effects of interpass temperature on the residual stress. And we found effective conditions for reducing tensile residual stress. To verify the validity of the conditions, specimens welded with or without water shower cooling were manufactured. Residual stresses of the specimens were experimentally measured. It was found that tensile residual stresses were generated on the surface of the welds and those were reduced in the case that the water-shower was applied. These measurement results agree well with the FEM analyses. It can therefore be concluded that the water-shower cooling during welding is appropriate for reducing tensile residual stress in austenitic stainless steel welding. (author)

  20. Standardized performance tests of collectors of solar thermal energy: Prototype moderately concentrating grooved collectors

    Science.gov (United States)

    1976-01-01

    Prototypes of moderately concentrating grooved collectors were tested with a solar simulator for varying inlet temperature, flux level, and incident angle. Collector performance is correlated in terms of inlet temperature and flux level.

  1. Nocturnal reverse flow in water-in-glass evacuated tube solar water heaters

    International Nuclear Information System (INIS)

    Tang, Runsheng; Yang, Yuqin

    2014-01-01

    Highlights: • Performance of water-in-glass evacuated tube solar water heaters (SWH) at night was studied. • Experimental measurements showed that reverse flow occurred in SWHs at night. • Reverse flow in SWHs was very high but the heat loss due to reverse flow was very low. • Reverse flow seemed not sensitive to atmospheric clearness but sensitive to collector tilt-angle. - Abstract: In this work, the thermal performance of water-in-glass evacuated tube solar water heaters (SWH) at nights was experimentally investigated. Measurements at nights showed that the water temperature in solar tubes was always lower than that in the water tank but higher than the ambient air temperature and T exp , the temperature of water inside tubes predicted in the case of the water in tubes being naturally cooled without reverse flow. This signified that the reverse flow in the system occurred at nights, making the water in solar tubes higher than T exp . It is found that the reverse flow rate in the SWH, estimated based on temperature measurements of water in solar tubes, seemed not sensitive to the atmospheric clearness but sensitive to the collector tilt-angle, the larger the tilt-angle of the collector, the higher the reverse flow rate. Experimental results also showed that, the reverse flow in the SWH was much higher as compared to that in a thermosyphonic domestic solar water heater with flat-plate collectors, but the heat loss from collectors to the air due to reverse flow in SWHs was very small and only took about 8–10% of total heat loss of systems

  2. Low temperature desalination using solar collectors augmented by thermal energy storage

    International Nuclear Information System (INIS)

    Gude, Veera Gnaneswar; Nirmalakhandan, Nagamany; Deng, Shuguang; Maganti, Anand

    2012-01-01

    Highlights: ► A new low temperature desalination process using solar collectors was investigated. ► A thermal energy storage tank (TES) was included for continuous process operation. ► Solar collector area and TES volumes were optimized by theoretical simulations. ► Economic analysis for the entire process was compared with and without TES tank. ► Energy and emission payback periods for the solar collector system were reported. -- Abstract: A low temperature desalination process capable of producing 100 L/d freshwater was designed to utilize solar energy harvested from flat plate solar collectors. Since solar insolation is intermittent, a thermal energy storage system was incorporated to run the desalination process round the clock. The requirements for solar collector area as well as thermal energy storage volume were estimated based on the variations in solar insolation. Results from this theoretical study confirm that thermal energy storage is a useful component of the system for conserving thermal energy to meet the energy demand when direct solar energy resource is not available. Thermodynamic advantages of the low temperature desalination using thermal energy storage, as well as energy and environmental emissions payback period of the system powered by flat plate solar collectors are presented. It has been determined that a solar collector area of 18 m 2 with a thermal energy storage volume of 3 m 3 is adequate to produce 100 L/d of freshwater round the clock considering fluctuations in the weather conditions. An economic analysis on the desalination system with thermal energy storage is also presented.

  3. Depressed collectors for millimeter wave gyrotrons

    International Nuclear Information System (INIS)

    Singh, A.; Granatstein, V.L.

    1992-01-01

    The main issues relating to design of depressed collectors for millimeter wave gyrotrons are discussed. A flow diagram is presented and the interlinking steps are outlined. Design studies are given for two kinds of gyrotrons on which severe constraints on the maximum radii of the collectors had been imposed; namely, for a cavity type and a quasi-optical gyrotron. A collector efficiency of the order of 70 percent is shown to be feasible for either case using careful tailoring of magnetic field profiles. A code has been developed to assist in doing this. A general approach toward initial placement of collectors has been indicated

  4. Water harvesting for young trees using Peltier plates powered by photovoltaic solar energy

    OpenAIRE

    Muñoz-García, Miguel Angel; Moreda Cantero, Guillermo P.; Raga Arroyo, Manuela Pilar; Marín González, Omar

    2012-01-01

    Young trees transplanted from nursery into open field require a minimum amount of soil moisture to successfully root in their new location, especially in dry-climate areas. One possibility is to obtain the required water from air moisture. This can be achieved by reducing the temperature of a surface below the air dew point temperature, inducing water vapor condensation on the surface. The temperature of a surface can be reduced by applying the thermoelectric effect, with Peltier modules powe...

  5. Comparative study to use nano-(Al2O3, CuO, and SiC) with water to enhance photovoltaic thermal PV/T collectors

    International Nuclear Information System (INIS)

    Al-Waeli, Ali H.A.; Chaichan, Miqdam T.; Kazem, Hussein A.; Sopian, K.

    2017-01-01

    Highlights: • Three types of nanoparticles (Al 2 O 3 , CuO and SiC) were added to water which was used as a base fluid. • The resulted nanofluid was used for cooling an indoor PV/T system. • The used nanofluids improved the thermal and electrical efficiencies of the PV/T system. • The stability of nanofluids was examined for an extended period and found to be stable. • SiC nanofluid showed better thermal conductivity and stability compared with Al 2 O 3 and CuO nanofluids. - Abstract: The reduction in efficiency of photovoltaic (PV) units due to increases in cell temperature occurs when a small part of the absorbed solar radiation is converted into electricity and the remaining part is lost as heat. Recently, the addition of a range of nanomaterials with high thermal conductivity to the cooling fluid in PV/T systems has been the subject of much research. In this study, three nanomaterials were added to water as a base fluid with several volume fractions to determine the best concentration and nanoparticle for this application. The PV/T system was setup in an indoor laboratory. Knowing which material has a better effect on the PV unit in particular, and the PV/T unit in general, is important for deciding which nanomaterial is more suitable for the system. The results reveal that nanofluid gives higher thermal conductivity with very little increase in the fluid density and viscosity compared with the base fluid. The studied volume fractions were 0.5, 1, 2, 3, and 4% and the selected nanoparticles were Al 2 O 3 , CuO, and SiC. It was found that silicon carbide nanoparticles have the best stability and the highest thermal conductivity compared to the other two nano-substances. Copper oxide nanofluid has higher thermal conductivity than aluminium oxide but lower stability, although it was found here that this material reliably stable compared to in other studies. The nanofluid reduced the indoor PV/T system temperature and enhanced its generated power.

  6. Thermal performance of an open thermosyphon using nanofluid for evacuated tubular high temperature air solar collector

    International Nuclear Information System (INIS)

    Liu, Zhen-Hua; Hu, Ren-Lin; Lu, Lin; Zhao, Feng; Xiao, Hong-shen

    2013-01-01

    Highlights: • A novel solar air collector with simplified CPC and open thermosyphon is designed and tested. • Simplified CPC has a much lower cost at the expense of slight efficiency loss. • Nanofluid effectively improves thermal performance of the above solar air collector. • Solar air collector with open thermosyphon is better than that with concentric tube. - Abstract: A novel evacuated tubular solar air collector integrated with simplified CPC (compound parabolic concentrator) and special open thermosyphon using water based CuO nanofluid as the working fluid is designed to provide air with high and moderate temperature. The experimental system has two linked panels and each panel includes an evacuated tube, a simplified CPC and an open thermosyphon. Outdoor experimental study has been carried out to investigate the actual solar collecting performance of the designed system. Experimental results show that air outlet temperature and system collecting efficiency of the solar air collector using nanofluid as the open thermosyphon’s working fluid are both higher than that using water. Its maximum air outlet temperature exceeds 170 °C at the air volume rate of 7.6 m 3 /h in winter, even though the experimental system consists of only two collecting panels. The solar collecting performance of the solar collector integrated with open thermosyphon is also compared with that integrated with common concentric tube. Experimental results show that the solar collector integrated with open thermosyphon has a much better collecting performance

  7. Dynamic Modeling of Natural Convection Solar Energy Flat Plate ...

    African Journals Online (AJOL)

    The analytical solutions to the dynamic model of an air-heating flat plate solar energy thermal collector were validated by direct measurement from a physical model constructed for that purpose, of the temperatures of the cover and absorber plates, the inlet and outlet fluids, and the ambient air from morning to evening for ...

  8. Potential application of glazed transpired collectors to space heating in cold climates

    International Nuclear Information System (INIS)

    Gao, Lixin; Bai, Hua; Mao, Shufeng

    2014-01-01

    Highlights: • A mathematical model for glazed transpired collectors (GTC) is developed. • Glazing results in optical loss, but it decreases convective heat loss effectively. • Thermal performance of GTC shows considerable improvement on flat-plate collectors. • GTC using recirculated air is applicable to space heating in cold climates. - Abstract: Although unglazed transpired collectors (UTC) succeed in industrial ventilation applications, solar fraction is very low when they are used in space heating in cold climates due to the lower exit air temperature. Considering the potential for glazed transpired collectors (GTC) using recirculated air for space heating applications in cold climates, a mathematical model is developed for predicting the thermal performance of GTC. Simulation results show that although glazing results in optical loss, it could decrease convective heat loss resulted from high crosswind velocities effectively. For a solar radiation of 400 W/m 2 , an ambient temperature of −10 °C, and a suction velocity of 0.01 m/s, the exit air temperature of GTC is higher than that of UTC for crosswind velocities exceeding 3.0 m/s. By comparison with a conventional flat-plate solar air collector operating under the same conditions, the thermal performance of GTC shows a significant improvement. For a five-storey hotel building located in the severe cold climate zone of China, case study shows that the annual solar fraction of the GTC-based solar air heating system is about 20%, which is two times higher than that of the flat-plate collector-based system and nearly nine times higher than that of the UTC-based system respectively. Hence, an enormous amount of energy will be saved with the application of GTC to space heating in cold climates

  9. An experimental investigation of the post-CHF enhancement factor for a prototypical ITER divertor plate with water coolant

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, T.D. [Rensselaer Polytechnic Institute, Troy, NY (United States); Watson, R.D.; McDonald, J.M. [Sandia National Lab., Albuquerque, NM (United States)] [and others

    1995-09-01

    In an off-normal event, water-cooled copper divertor plates in the International Thermonuclear Experimental Reactor (ITER) may either experience heat loads beyond their design basis, or the normal heat loads may be accompanied by low coolant pressure and velocity. The purpose of this experiment was to illustrate that during one-sided heating, as in ITER, a copper divertor plate with the proper side wall thickness, at low system pressure and velocity can absorb without failing an incident heat flux, q{sub i}, that significantly exceed the value, q{sub i}{sup CHF}, which is associated with local CHF at the wall of the coolant channel. The experiment was performed using a 30 kW electron beam test system for heating of a square cross-section divertor heat sink with a smooth circular channel of 7.63 mm diameter. The heated width, length, and wall thickness were 16, 40, and 3 mm, respectively. Stable surface temperatures were observed at incident heat fluxes greater than the local CHF point, presumably due to circumferential conduction around the thick tube walls when q{sub i}{sup CHF} was exceeded. The Post-CHF enhancement factor, {eta}, is defined as the ratio of the incident burnout heat flux, q{sub i}{sup BO}, to q{sub i}{sup CHF}. For this experiment with water at inlet conditions of 70{degrees}C, 1 m/s, and 1 MPa, q{sub i}{sup CHF} and q{sub i}{sup BO} were 600 and 1100 W/cm{sup 2}, respectively, which gave an {eta} of 1.8.

  10. Study on collapse behavior of a square plate subjected to water pressure; Suiatsu wo ukeru kukeiban no atsukai kyodo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Yao, T; Fujikubo, M; Mizutani, K [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1996-04-10

    Bottom plates of a hull are subjected to laterally distributing force due to in-plane compression force and water pressure in the ship`s length direction as a result of longitudinal bending in a hogging condition. Because buckling collapse of the hull bottom plates leads directly to longitudinal bending collapse of the hull bottom cross section, the hull bottom plates must have sufficient strength. The present study performs a static elastic large deflection analysis and an elasto-plastic large deflection analysis. It elucidates buckling collapse behavior of a square plate subjected to water pressure and in-plane compression load, and considers limits in application of conventional approximation analysis methods. In the case of a water pressure action, deflection components growing in excess of the buckling load do not necessarily correspond to buckling modes of the case where no water pressure is acting upon. Conventional approximation analysis methods may not be able often to pursue actual buckling phenomena. According the result of an analysis on hull bottom panels of an actual ship, the ultimate strength decreases when the water pressure is large. Compression force in the lateral direction as a result of water pressure acting on ship`s sides affected very little the ultimate strength. 3 refs., 7 figs.

  11. Simulation of the solar hot water systems diffusion: the case of Greece

    International Nuclear Information System (INIS)

    Sidiras, D.; Koukios, E.

    2004-01-01

    The main object of this paper is the documentation and study of the main factors behind the spectacular diffusion of solar energy use for domestic hot water production in Greece. The time pattern of the diffusion of flat-plate solar collectors since its 'out of the blue' first appearance in 1974, shows that the diffusion rate grew exponentially at first, with the annual sales figure reaching 91,000 m 2 by 1980. A rate slow down in the early 1980s was followed by a brief period of explosive growth, with the annual sales figure reaching its peak value of more than 185,000 m 2 in mid-1980s. A rapid decline of the growth rate down to the present annual sales level followed. The installed solar collectors pattern has the characteristic form of an S-shape curve, representing the overall penetration of the flat-plate solar collector use for domestic hot water production in the Greek economy and society. This evolution has gone through an inflection point around 1987, i.e. at a time when about 1,000,000 m 2 of collectors had already been installed. By the year 2000, about 2,070,000 m 2 of collectors had been installed, with a tendency to level off by 2010, unless some the present conditions determining this phenomenon change. (author)

  12. Models of the heat dynamics of solar collectors for performance testing

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Perers, Bengt

    2011-01-01

    accurate estimates of parameters in physical models. The applied method is described by Kristensen et al. (2004) and implemented in the software CTSM1. Examples of successful applications of the method includes modelling the of the heat dynamics of integrated photo-voltaic modules (Friling et al., 2009......) and modelling of the heat dynamics of buildings (Madsen and Holst, 1995). Measurements obtained at a test site in Denmark during the spring 2010 are used for the modelling. The tested collector is a single glazed large area flat plate collector with selective absorber and Teflon anti convection layer. The test...

  13. Foldable Frame Supporting Electromagnetic Radiation Collectors

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to flexible frames supporting electromagnetic radiation collectors, such as antennas, antenna reflectors, deflectors or solar collectors, for celestial or terrestrial applications, which can be folded to be stored and/or transported. The method for stowing deforms...

  14. EFFECT OF BLENDING VARIOUS COLLECTORS AT BULK ...

    African Journals Online (AJOL)

    Nkana Concentrator under the ownership of the then Zambia Consolidated Copper Mines Ltd (ZCCM) had been using Sodium Ethyl Xanthate (SEX) mainly as a collector, but with the coming of new Mopani Copper Mines Plc (M.C.M), it was felt that there was a need to test alternative collectors in an attempt to improve the ...

  15. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  16. OUT Success Stories: Transpired Solar Collectors

    International Nuclear Information System (INIS)

    Clyne, R.

    2000-01-01

    Transpired solar collectors are a reliable, low-cost technology for preheating building ventilation air. With simple payback periods ranging from 3 to 12 years and an estimated 30-year life span, transpired collector systems offer building owners substantial cost savings

  17. Integrated solar water-heater and solar water cooler performance during winter time

    International Nuclear Information System (INIS)

    Shaikh, N.U.; Siddiqui, M.A

    2012-01-01

    Solar powered water heater and water cooler is an important contribution for the reduction of fossil fuel consumptions and harmful emissions to the environment. This study aims to harness the available solar potential of Pakistan and provide an option fulfilling the domestic hot and cold water demands during winter and summer seasons respectively. The system was designed for the tap-water temperature of 65 degree C (149 degree F) and the chilled drinking-water temperature of 14 degree C (57 degree F) that are the recommended temperatures by World Health Organization (WHO). The solar water heater serves one of the facilities of the Department of Mechanical Engineering at NED University of Engineering and Technology whereas, the solar water cooler will provide drinking water to approximately 50 people including both faculty and students. A pair of single glazed flat plate solar collector was installed to convert solar radiations to heat. Hot water storage and supply system was carefully designed and fabricated to obtain the designed tap-water temperature. Vapour-absorption refrigeration system was designed to chill drinking water. Intensity of solar radiations falling on the solar collector, water temperatures at the inlet and outlet of the solar collectors and the tap water temperature were measured and analyzed at different hours of the day and at different days of the month. The results show that the installed solar collector system has potential to feed hot water of temperatures ranging from 65 degree C (149 degree F) to 70 Degree C (158 degree F), that is the required hot water temperature to operate a vapour absorption chilled water production system. (author)

  18. Solar heating and hot water system installed at James Hurst Elementary School, Portsmouth, Virginia

    Science.gov (United States)

    1981-01-01

    Solar heating and a hot water system installed in an elementary school in Portsmouth, Virginia are examined. The building is zoned into four heating/cooling areas. Each area is equipped with an air handling unit that is monitored and controlled by central control and monitoring system. The solar system for the building uses a collector area of 3,630 sq. ft. of flat plate liquid collectors, and a 6,000 gallon storage tank. System descriptions, maintenance reports, detailed component specifications, and design drawings to evaluate this solar system are reported.

  19. Solar hot water system installed at Las Vegas, Nevada. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    The solar hot water system installed at LaQuinta Motor Inn Inc., at Las Vegas, Nevada is described. The Inn is a three-story building with a flat roof for installation of the solar panels. The system consists of 1200 square feet of liquid flat plate collectors, a 2500 gallon insulated vertical steel storage tank, two heat exchangers and pumps and controls. The system was designed to supply approximately 74 percent of the total hot water load.

  20. A plate reader-based method for cell water permeability measurement

    DEFF Research Database (Denmark)

    Fenton, Robert A.; Moeller, H B; Nielsen, S

    2010-01-01

    Cell volume and water permeability measurements in cultured mammalian cells are typically conducted under a light microscope. Many of the employed approaches are time consuming and not applicable to a study of confluent epithelial cell monolayers. We present here an adaptation of a calcein......: AQP2-S256D > AQP2 wild-type > AQP2-S256A. We propose that the method can be applied to study AQP function and more generally to study cell volume changes in adherent cell lines. Furthermore, it should be adaptable for AQP inhibitor screening in chemical compound libraries....

  1. Thermal study of a residential water solar heating system with two different absorbing surface configurations; Estudo termico de um sistema solar de aquecimento de agua residencial para duas configuracoes de superficie absorvedora

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Rivaldo Ferreira

    2009-10-15

    A solar collector to be used in a system for heating water for bathing, whose main characteristics are its low cost and easy manufacturing and assembly is presented. The absorbing surface of the collector is formed by an aluminum plate with eight flaps where they lodge PVC pipes. The catchment area of solar radiation corresponds to 1.3 meters. The collector box was made of wood, it is covered by transparent glass and thermal insulation of tire chips and expanded polystyrene (EPS). Absorber tubes were connected in parallel through the use of PVC fittings and fixed to the plate by the use of metal poles and rivets. The entire absorber received paint fiat black for better absorption of sunlight. The system worked on a thermosyphon assembly and absorber of the collector has been tested in two configurations: with the tubes facing up, directly exposed to the impact of sunlight and facing down, exchanging heat with the plate by conduction. The most efficient configuration for the connect purpose was determined. The solar collector was connected to a thermal reservoir, also alternative, low-cost forming the system of solar water heating. We evaluated thermal parameters that proved the viability of the heating system studied. (author)

  2. Design, construction and testing of a low-cost flat plate solar energy ...

    African Journals Online (AJOL)

    A low-cost flat plate solar energy collector has been designed and constructed with locally available materials such as mild steel and black paint of absorptance 0.94. On testing, an average daily efficiency of 55.6% was obtained. The methods are simple and illustrate the fact that construction of efficient collectors are ...

  3. Review of state-of-the-art of solar collector corrosion processes. Task 1 of solar collector studies for solar heating and cooling applications. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, J E; Diegle, R B

    1980-04-11

    The state-of-the-art of solar collector corrosion processes is reviewed, and Task 1 of a current research program on use of aqueous heat transfer fluids for solar heating and cooling is summarized. The review of available published literature has indicated that lack of quantitative information exists relative to collector corrosion at the present time, particularly for the higher temperature applications of solar heating and cooling compared to domestic water heating. Solar collector systems are reviewed from the corrosion/service life viewpoint, with emphasis on various applications, collector design, heat transfer fluids, and freeze protection methods. Available information (mostly qualitative) on collector corrosion technology is reviewed to indicate potential corrosion problem areas and corrosion prevention practices. Sources of limited quantitative data that are reviewed are current solar applications, research programs on collector corrosion, and pertinent experience in related applications of automotive cooling and non-solar heating and cooling. A data bank was developed to catalog corrosion information. Appendix A of this report is a bibliography of the data bank, with abstracts reproduced from presently available literature accessions (about 220). This report is presented as a descriptive summary of information that is contained in the data bank.

  4. Development of a brazing process for the production of water- cooled bipolar plates made of chromium-coated metal foils for PEM fuel cells

    International Nuclear Information System (INIS)

    Mueller, M; Hoehlich, D; Scharf, I; Lampke, T; Hollaender, U; Maier, H J

    2016-01-01

    Beside lithium batteries, PEM fuel cells are the most promising strategy as a power source to achieve the targets for introducing and increasing the usage of electric vehicles. Due to limited space and weight problems, water cooled, metallic bipolar plates in a fuel cell metal stack are preferred in motor vehicles. These plates are stamped metal sheets with a complex structure, interconnected media-tight. To meet the multiple tasks and requirements in use, complex and expensive combinations of materials are currently in use (carbon fiber composites, graphite, gold-plated nickel, stainless and acid resistant steel). The production of such plates is expensive as it is connected with considerable effort or the usage of precious metals. As an alternative, metalloid nitrides (CrN, VN, W 2 N, etc.) show a high chemical resistance, hardness and a good conductivity. So this material category meets the basic requirements of a top layer. However, the standard methods for their production (PVD, CVD) are expensive and have a slow deposition rate and a lower layer thicknesses. Because of these limitations, a full functionality over the life cycle of a bipolar plate is not guaranteed. The contribution shows the development and quantification of an alternative production process for bipolar plates. The expectation is to get significant advantages from the combination of chromium electrodeposition and thermochemical treatment to form chromium nitrides. Both processes are well researched and suitable for series production. The thermochemical treatment of the chromium layer also enables a process-integrated brazing. (paper)

  5. A finite-volume model of a parabolic trough photovoltaic/thermal collector: Energetic and exergetic analyses

    International Nuclear Information System (INIS)

    Calise, Francesco; Palombo, Adolfo; Vanoli, Laura

    2012-01-01

    This paper presents a detailed finite-volume model of a concentrating photovoltaic/thermal (PVT) solar collector. The PVT solar collector consists in a parabolic trough concentrator and a linear triangular receiver. The bottom surfaces of the triangular receiver are equipped with triple-junction cells whereas the top surface is covered by an absorbing surface. The cooling fluid (water) flows inside a channel along the longitudinal direction of the PVT collector. The system was discretized along its axis and, for each slice of the discretized computational domain, mass and energy balances were considered. The model allows one to evaluate both thermodynamic and electrical parameters along the axis of the PVT collector. Then, for each slice of the computational domain, exergy balances were also considered in order to evaluate the corresponding exergy destruction rate and exergetic efficiency. Therefore, the model also calculates the magnitude of the irreversibilities inside the collector and it allows one to detect where these irreversibilities occur. A sensitivity analysis is also performed with the scope to evaluate the effect of the variation of the main design/environmental parameters on the energetic and exergetic performance of the PVT collector. -- Highlights: ► The paper investigates an innovative concentrating photovoltaic thermal solar collector. ► The collector is equipped with triple-junction photovoltaic layers. ► A local exergetic analysis is performed in order to detect sources of irreversibilities. ► Irreversibilities are mainly due to the heat transfer between sun and PVT collector.

  6. The influence of walls and upper tie plate slots on the flooding mechanism in fuel elements with and without heat transfer between steam and water

    International Nuclear Information System (INIS)

    Spatz, R.; Mewes, D.

    1989-01-01

    The counter-current flow of steam and water was experimentally investigated for the upper part of a PWR fuel element. The actual geometrical shape of the nuclear equipment was simulated by various types of plates, in which bore holes and slots were arranged in different positions. The experiments were performed with and without an installed, unheated rod bundle below the plates. The water was injected at saturated and subcooled temperatures in order to observe the effects of heat transfer on counter-current flow. With increasing steam velocity the flooding occurs initially in the tie-plate area. If the rod bundle is installed in the flow duct, a part of the downwards flowing water is transported upwards from the region of the upper grid spacer to the plate. Heat transfer between the phases can cause in the counter-current flow region an instable transition from downward to near complete upward directed liquid flow. In comparison to experiments with saturated water injection, flooding occurs at larger steam velocities. Different flooding correlations, which are known from the literature, were compared with the experimental data to appraise their applicability to counter-current flow in the core of PWRs. (orig.)

  7. Double-pass photovoltaic / thermal (PV/T) solar collector with advanced heat transfer features

    International Nuclear Information System (INIS)

    Mohd Nazari Abu Bakar; Baharudin Yatim; Mohd Yusof Othman; Kamaruzzaman Sopian

    2006-01-01

    The use of PV/T in combination with concentrating reflectors has a potential to significantly increase power production from a given solar cell area. A prototype double-pass photovoltaic-thermal solar air collector with CPR and fins has been designed and fabricated and its performance over a range of operating conditions was studied. The absorber of the hybrid photovoltaic / thermal (PV/T) collector under investigation consists of an array of solar cells for generating electricity, compound parabolic concentrator (CPR) to increase the radiation intensity falling on the solar cells and fins attached to the back side of the absorber plate to improve heat transfer to the flowing air. The thermal, electrical and combined electrical and thermal efficiencies of the collector are presented and discussed

  8. Condensation heat transfer correlation for water-ethanol vapor mixture flowing through a plate heat exchanger

    Science.gov (United States)

    Zhou, Weiqing; Hu, Shenhua; Ma, Xiangrong; Zhou, Feng

    2018-04-01

    Condensation heat transfer coefficient (HTC) as a function of outlet vapor quality was investigated using water-ethanol vapor mixture of different ethanol vapor concentrations (0%, 1%, 2%, 5%, 10%, 20%) under three different system pressures (31 kPa, 47 kPa, 83 kPa). A heat transfer coefficient was developed by applying multiple linear regression method to experimental data, taking into account the dimensionless numbers which represents the Marangoni condensation effects, such as Re, Pr, Ja, Ma and Sh. The developed correlation can predict the condensation performance within a deviation range from -22% to 32%. Taking PHE's characteristic into consideration and bringing in Ma number and Sh number, a new correlation was developed, which showed a much more accurate prediction, within a deviation from -3.2% to 7.9%.

  9. Outdoor Performance Analysis of a Photovoltaic Thermal (PVT) Collector with Jet Impingement and Compound Parabolic Concentrator (CPC)

    OpenAIRE

    Ahed Hameed Jaaz; Husam Abdulrasool Hasan; Kamaruzzaman Sopian; Abdul Amir H. Kadhum; Tayser Sumer Gaaz; Ahmed A. Al-Amiery

    2017-01-01

    This paper discusses the effect of jet impingement of water on a photovoltaic thermal (PVT) collector and compound parabolic concentrators (CPC) on electrical efficiency, thermal efficiency and power production of a PVT system. A prototype of a PVT solar water collector installed with a jet impingement and CPC has been designed, fabricated and experimentally investigated. The efficiency of the system can be improved by using jet impingement of water to decrease the temperature of the solar ce...

  10. Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1995-01-01

    1.1 This practice provides a procedure for the exposure of cover materials for flat-plate solar collectors to the natural weather environment at temperatures that are elevated to approximate operating conditions. 1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials. 1.3 This practice does not apply to cover materials for evacuated collectors or photovoltaics. 1.4 The values stated in SI units are to be regarded as the standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  11. IMPACT OF SOLAR RADIATION CHANGE ON THE COLLECTOR EFFICIENTLY

    Directory of Open Access Journals (Sweden)

    Danuta Proszak-Miąsik

    2017-01-01

    Full Text Available In October 2014 in a building of Rzeszow University of Technology, a series of measurements was taken to calculate the parameters of a solar system with a flat collector, as installed on the roof of the building. The following parameters were obtained: the value of solar radiation intensity, the temperature of external air, the temperature on the collector, the temperature of water in the tank and the temperature of glycol on the supply and return lines. On the basis of the data received, charts were made to visually present how changes of solar radiation intensity affected parameters of the system. The study was conducted in autumn when the intensity of solar radiation decreases, compared with summer months. The publication aims to show that the solar system brings energy gains in periods of transition, and the instantaneous intensity of solar radiation are comparable to those in the summer.

  12. Cold plate

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin, Christopher M.; O' Connell, Kevin M.; Schultz, Mark D.; Tian, Shurong

    2018-02-13

    A cold plate, an electronic assembly including a cold plate, and a method for forming a cold plate are provided. The cold plate includes an interface plate and an opposing plate that form a plenum. The cold plate includes a plurality of active areas arranged for alignment over respective heat generating portions of an electronic assembly, and non-active areas between the active areas. A cooling fluid flows through the plenum. The plenum, at the non-active areas, has a reduced width and/or reduced height relative to the plenum at the active areas. The reduced width and/or height of the plenum, and exterior dimensions of cold plate, at the non-active areas allow the non-active areas to flex to accommodate surface variations of the electronics assembly. The reduced width and/or height non-active areas can be specifically shaped to fit between physical features of the electronics assembly.

  13. Single-stage depressed collectors for gyrotrons

    International Nuclear Information System (INIS)

    Piosczyk, B.; Iatrou, C.T.; Dammertz, G.; Thumm, M.; Univ. Karlsruhe

    1996-01-01

    Two 140 GHz gyrotrons with a single-step depressed collector have been operated. The different position of the isolating collector gap in the stray magnetic field causes the electron motion in the retarding region to be in one case adiabatic and in the other case nonadiabatic. The kind of motion within the retarding field influences strongly the behavior of the gyrotron with a depressed collector. In the case of nonadiabatic motion a significant amount of transverse momentum is given to the electrons reflected at the collector potential. This causes the reflected electrons to be trapped between the magnetic mirror and the collector. The electrons escape from the trap by diffusion across the magnetic field to the body of the tube thus contributing to the body current. Despite the high body current there is no observable influence of the collector voltage on the RF output power. In the case of adiabatic motion the reflected electrons do not gain a sufficient amount of transverse momentum to be trapped by the magnetic mirror. They pass the cavity toward the gun and they are trapped between the negative gun potential and the collector. The interaction with the RF field by electrons traveling through the cavity enhances the diffusion in the velocity space thus enabling the trapped electrons to overcome the potential barrier and escape toward the collector. Therefore the body current stays at low values since in this case the reflected electrons do not contribute to it. However, at higher collector voltages a reduction of RF power occurred and some noise in the electron beam was observed. The main motivation for the development of gyrotrons in the frequency range above 100 GHz with power levels in excess of several hundreds kW per tube, is the application in magnetic fusion devices for plasma heating and for electron current drive

  14. Plating laboratory

    International Nuclear Information System (INIS)

    Seamster, A.G.; Weitkamp, W.G.

    1984-01-01

    The lead plating of the prototype resonator has been conducted entirely in the plating laboratory at SUNY Stony Brook. Because of the considerable cost and inconvenience in transporting personnel and materials to and from Stony Brook, it is clearly impractical to plate all the resonators there. Furthermore, the high-beta resonator cannot be accommodated at Stony Brook without modifying the set up there. Consequently the authors are constructing a plating lab in-house

  15. Performance analysis of a heat pipe solar collector having different pitch distance

    Energy Technology Data Exchange (ETDEWEB)

    Sivaraman, B.; Mohan, N.K. [Annamalai Univ., Tamil Nadu (India). Dept. of Mechanical Engineering

    2006-07-01

    Heat pipe solar collectors are more efficient than conventional solar collectors. This paper provided details of experimental analyses conducted to examine the effect of pitch distance on the heat pipe's performance. Two solar collectors with pitch distances of 7.5 cm and 8.5 cm were used in the study. Copper tubing was used as the container material, and methanol was selected as a working fluid for the experiments, which were conducted during the summer at a collector tilt angle of 11 degrees. Experiments were conducted and the impacts of various parameters were measured. Solar intensity was measured using a pyranometer. Water exit and inlet temperatures were measured using mercury thermometers. Results showed that the heat pipe performed optimally when the pitch distance was 0.085 m. 8 refs., 1 tab., 9 figs.

  16. Engineering design of 500KW CW collector

    International Nuclear Information System (INIS)

    Kumar, Ramesh; Mishra, Deepak; Prasad, M.; Hannuarakar, P.R.

    2006-01-01

    An electron beam collector for 500kW beam power has been designed to test the electron gun. The gun is designed for 250kW, 350MHz CW Klystron with 50% efficiency. This will also help in preliminary studies related to final collector design for Klystron. This paper presents the design parameters, thermal analysis and mechanical features of the design. Electron trajectory on inside wall of the collector is determined with EGUN and computational flow dynamics simulation was done on ANSYS for cooling requirements. (author)

  17. Next Generation Solar Collectors for CSP

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Attila [3M Company, St. Paul, MN (United States); Charles, Ruth [3M Company, St. Paul, MN (United States)

    2014-07-31

    The intent of “Next Generation Solar Collectors for CSP” program was to develop key technology elements for collectors in Phase 1 (Budget Period 1), design these elements in Phase 2 (Budget Period 2) and to deploy and test the final collector in Phase 3 (Budget Period 3). 3M and DOE mutually agreed to terminate the program at the end of Budget Period 1, primarily due to timeline issues. However, significant advancements were achieved in developing a next generation reflective material and panel that has the potential to significantly improve the efficiency of CSP systems.

  18. The lower limiting values of collector properties based on core data

    Energy Technology Data Exchange (ETDEWEB)

    Mitrofanov, V P; Tul' bovich, B I

    1982-01-01

    There are numerous methods for determining the lower limiting values of collector properties; which is caused by complexity of studying objects, the utilization of different petrophysical parameters and characteristics of formation productiveness. Based on laboratory studies conducted at PermNIPIneft', two methods of determining the limited values of collector properties were examined with consideration of data from existing literature: 1) from the critical water saturation content K /SUB b/ *; 2) using the phase permeability for kerosene or oil K /SUB prk/. In the first case the value of K /SUB b/ * is determined from the presence of filtering of a two-face flow with the oil fraction not less than 2%. Knowing the value of K /SUB b/ *, the limiting values of collector properties are evaluated by using the petrophysical relationships, which reflect the connection between residual water saturation, permeability for a gas, porosity, the complex parameter ..sqrt.. K /SUB prg/ /K /SUB p/, and also by the effective porosity. In the second case determination of the phase permeability K /SUB prk/ for collectors with low permeability allows one to establish limiting values of collector properties of permeability. Transition to the porosity limit is achieved by the relationship of gas permeability to open or effective porosity. The examining methods for determining lower limiting values of collector properties are used in calculating the reserve of 9 deposits in the Permian region.

  19. Improved Large Aperture Collector Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    O' Rourke, Deven [Abengoa Solar LLC, Lakewood, CO (United States); Farr, Adrian [Abengoa Solar LLC, Lakewood, CO (United States)

    2015-12-01

    The parabolic trough is the most established CSP technology and carries a long history of design experimentation dating back to the 1970’s. This has led to relatively standardized collector architectures, a maturing global supply chain, and a fairly uniform cost reduction strategy. Abengoa has deployed more than 1,500MWe of CSP troughs across several countries and has built and tested full-scale prototypes of many R&D concepts. The latest trough R&D efforts involved efforts to internalize non-CSP industry experience including a preliminary DFMA principles review done with Boothroyd Dewhurst, a construction literature review by the Arizona State University School of Construction Management, and two more focused manufacturing engineering subcontracts done by Ricardo Inc. and the nonprofit Edison Welding Institute. The first two studies highlighted strong opportunities in lowering part count, standardizing components and fasteners, developing modular designs to support prefabrication and automation, and devising simple, error-proof manual assembly methods. These principles have delivered major new cost savings in otherwise “mature” products in analogous industries like automotive, truck trailer manufacture, metal building fabrication, and shipbuilding. For this reason, they were core in the design development of the SpaceTube® collector, and arguably key to its early successes. The latter two studies were applied specifically to the first-generation SpaceTube® design and were important in setting the direction of the present SolarMat project. These studies developed a methodology to analyze the costs of manufacture and assembly, and identify new tooling concepts for more efficient manufacture. Among the main opportunities identified in these studies were the automated mirror arm manufacturing concept and the need for a less infrastructure-intensive assembly line, both of which now form central pillars of the SolarMat project strategy. These new designs will be

  20. Performance of a Solar Heating System with Photovoltaic Thermal Hybrid Collectors and Heat Pump

    DEFF Research Database (Denmark)

    Dannemand, Mark; Furbo, Simon; Perers, Bengt

    2017-01-01

    . When the solar collectors are unable to supply the heat demand an auxiliary heat source is used. Heat pumps can generate this heat. Liquid/water heat pumps have better performance than air/water heat pumps in cold climates but requires installation of a tubing system for the cold side of the heat pump....... The tubes are typically placed in the ground, requires a significant land area and increase the installation cost. A new system design of a solar heating system with two storage tanks and a liquid/water heat pump is presented. The system consists of PVT collectors that generate both heat and electricity......The energy consumption in buildings accounts for a large part of the World’s CO2 emissions. Much energy is used for appliances, domestic hot water preparation and space heating. In solar heating systems, heat is captured by solar collectors when the sun is shining and used for heating purposes...

  1. Water cooled nuclear reactor

    International Nuclear Information System (INIS)

    1975-01-01

    A description is given of a cooling water intake collector for a nuclear reactor. It includes multiple sub-collectors extending out in a generally parallel manner to each other, each one having a first end and a second one separated along their length, and multiple water outlets for connecting each one to a corresponding pressure tube of the reactor. A first end tube and a second one connect the sub-collector tubes together to their first and second ends respectively. It also includes multiple collector tubes extending transversely by crossing over the sub-collector tubes and separated from each other in the direction of these tubes. Each collector tubes has a water intake for connecting to a water pump and multiple connecting tubes separated over its length and connecting each one to the corresponding sub-collector [fr

  2. Design and fabrication of light weight current collectors for direct methanol fuel cells using the micro-electro mechanical system technique

    Science.gov (United States)

    Sung, Min-Feng; Kuan, Yean-Der; Chen, Bing-Xian; Lee, Shi-Min

    The direct methanol fuel cell (DMFC) is suitable for portable applications. Therefore, a light weight and small size is desirable. The main objective of this paper is to design and fabricate a light weight current collector for DMFC usage. The light weight current collector mainly consists of a substrate with two thin film metal layers. The substrate of the current collector is an FR4 epoxy plate. The thin film metal layers are accomplished by the thermo coater technique to coat metal powders onto the substrate surfaces. The developed light weight current collectors are further assembled to a single cell DMFC test fixture to measure the cell performance. The results show that the proposed current collectors could even be applied to DMFCs because they are light, thin and low cost and have potential for mass production.

  3. Optimal nonimaging integrated evacuated solar collector

    Science.gov (United States)

    Garrison, John D.; Duff, W. S.; O'Gallagher, Joseph J.; Winston, Roland

    1993-11-01

    A non imaging integrated evacuated solar collector for solar thermal energy collection is discussed which has the lower portion of the tubular glass vacuum enveloped shaped and inside surface mirrored to optimally concentrate sunlight onto an absorber tube in the vacuum. This design uses vacuum to eliminate heat loss from the absorber surface by conduction and convection of air, soda lime glass for the vacuum envelope material to lower cost, optimal non imaging concentration integrated with the glass vacuum envelope to lower cost and improve solar energy collection, and a selective absorber for the absorbing surface which has high absorptance and low emittance to lower heat loss by radiation and improve energy collection efficiency. This leads to a very low heat loss collector with high optical collection efficiency, which can operate at temperatures up to the order of 250 degree(s)C with good efficiency while being lower in cost than current evacuated solar collectors. Cost estimates are presented which indicate a cost for this solar collector system which can be competitive with the cost of fossil fuel heat energy sources when the collector system is produced in sufficient volume. Non imaging concentration, which reduces cost while improving performance, and which allows efficient solar energy collection without tracking the sun, is a key element in this solar collector design.

  4. Humidification dehumidification desalination system using parabolic trough solar air collector

    International Nuclear Information System (INIS)

    Al-Sulaiman, Fahad A.; Zubair, M. Ifras; Atif, Maimoon; Gandhidasan, Palanichamy; Al-Dini, Salem A.; Antar, Mohamed A.

    2015-01-01

    This paper deals with a detailed thermodynamic analysis to assess the performance of an HDH system with an integrated parabolic trough solar collector (PTSC). The HDH system considered is an open air, open water, air heated system that uses a PTSC as an air heater. Two different configurations were considered of the HDH system. In the first configuration, the solar air heater was placed before the humidifier whereas in the second configuration the solar air heater was placed between the humidifier and the dehumidifier. The current study revealed that PTSCs are well suited for air heated HDH systems for high radiation location, such as Dhahran, Saudi Arabia. The comparison between the two HDH configurations demonstrates that the gained output ratio (GOR) of the first configuration is, on average, about 1.5 whereas for the second configuration the GOR increases up to an average value of 4.7. The study demonstrates that the HDH configuration with the air heater placed between the humidifier and the dehumidifier has a better performance and a higher productivity. - Highlights: • Thermodynamic analysis of an HDH system driven by a parabolic trough solar collector was conducted. • The first configuration reveals a GOR of 1.5 while the second configuration reveals a GOR of 4.7. • Effective heating of the HDH system was obtained through parabolic trough solar collector

  5. Determination of absorbed dose to water from a miniature kilovoltage x-ray source using a parallel-plate ionization chamber

    Science.gov (United States)

    Watson, Peter G. F.; Popovic, Marija; Seuntjens, Jan

    2018-01-01

    Electronic brachytherapy sources are widely accepted as alternatives to radionuclide-based systems. Yet, formal dosimetry standards for these devices to independently complement the dose protocol provided by the manufacturer are lacking. This article presents a formalism for calculating and independently verifying the absorbed dose to water from a kV x-ray source (The INTRABEAM System) measured in a water phantom with an ionization chamber calibrated in terms of air-kerma. This formalism uses a Monte Carlo (MC) calculated chamber conversion factor, CQ , to convert air-kerma in a reference beam to absorbed dose to water in the measurement beam. In this work CQ was determined for a PTW 34013 parallel-plate ionization chamber. Our results show that CQ was sensitive to the chamber plate separation tolerance, with differences of up to 15%. CQ was also found to have a depth dependence which varied with chamber plate separation (0 to 10% variation for the smallest and largest cavity height, over 3 to 30 mm depth). However for all chamber dimensions investigated, CQ was found to be significantly larger than the manufacturer reported value, suggesting that the manufacturer recommended method of dose calculation could be underestimating the dose to water.

  6. A Soil-Plate Based Pipeline for Assessing Cereal Root Growth in Response to Polyethylene Glycol (PEG)-Induced Water Deficit Stress.

    Science.gov (United States)

    Nelson, Sven K; Oliver, Melvin J

    2017-01-01

    Drought is a serious problem that causes losses in crop-yield every year, but the mechanisms underlying how roots respond to water deficit are difficult to study under controlled conditions. Methods for assaying root elongation and architecture, especially for seedlings, are commonly achieved on artificial media, such as agar, moistened filter paper, or in hydroponic systems. However, it has been demonstrated that measuring root characteristics under such conditions does not accurately mimic what is observed when plants are grown in soil. Morphological changes in root behavior occur because of differences in solute diffusion, mechanical impedance, exposure to light (in some designs), and gas exchange of roots grown under these conditions. To address such deficiencies, we developed a quantitative method for assaying seedling root lengths and germination in soil using a plate-based approach with wheat as a model crop. We also further developed the method to include defined water deficits stress levels using the osmotic properties of polyethylene glycol (PEG). Seeds were sown into soil-filled vertical plates and grown in the dark. Root length measurements were collected using digital photography through the transparent lid under green lighting to avoid effects of white light exposure on growth. Photographs were analyzed using the cross-platform ImageJ plugin, SmartRoot, which can detect root edges and partially automate root detection for extraction of lengths. This allowed for quick measurements and straightforward and accurate assessments of non-linear roots. Other measurements, such as root width or angle, can also be collected by this method. An R function was developed to collect exported root length data, process and reformat the data, and output plots depicting root/shoot growth dynamics. For water deficit experiments, seedlings were transplanted side-by-side into well-watered plates and plates containing PEG solutions to simulate precise water deficits.

  7. Low and medium temperature solar thermal collector based in innovative materials and improved heat exchange performance

    International Nuclear Information System (INIS)

    Fernández, A.; Dieste, J.A.

    2013-01-01

    Highlights: • We designed, built and tested 2 different prototypes of thermal collector. • We included polymeric materials and suppressed pipes for freeform optimization. • Efficiency of the collector achieved values as high as commercial ones. • We provided a low cost and high volume production product. - Abstract: A low and medium temperature solar thermal collector for economical supply of heat between 40 and 90 °C has been developed. It is based on solar concentrating systems, heat transfer optimization and substitution of metallic materials by plastic ones. The basic concept is the integration of a flat absorber strip inside semicircular reflector channels in contact with heated water without pressurization. This collector is intended to be more efficient and cheaper than what actual commercial collectors usually are so that the access to a clean and renewable energy would be more quickly redeemable and its use more effective during its life cycle, expanding its common application range. The substitution of traditional materials by surface treated Aluminum with TiNOx for the absorber and chromed thermoformed ABS for the reflector simplifies the production and assembly process. The definitive prototype has an aperture area of 0.225 m 2 . It was tested in Zaragoza (Spain) and the accumulated efficiency was between 41% and 57%, and the instantaneous efficiency reached 98% depending on the weather conditions. As all trials were made in parallel with a commercial collector, in several cases the performance was over the commercial one

  8. Architectural integration of energy solar collectors made with ceramic materials and suitable for the Mediterranean climate

    Directory of Open Access Journals (Sweden)

    J. Roviras

    2016-12-01

    Full Text Available The work presented here aims to demonstrate the technical, architectural and energy viability of solar thermal collectors made with ceramic materials and the Mediterranean climate suitable for the production of domestic hot water (DHW and for heating systems in buildings. The design of a ceramic shell formed by panels collectors and panels no sensors, which are part of the same building system that is capable of responding to the basic requirements of a building envelope and capture solar energy is proposed. Ceramics considerably reduced the final cost of the sensor system and offers the new system a variety of compositional and chromatic since, with reduced performance compared to a conventional metallic collector, can occupy the entire surface of front and get a high degree of architectural integration. A tool for assessing the new ceramic solar collector has been defined from a multi-criteria perspective: economic, environmental and social. The tool enables the comparison of the ceramic solar collector with solar collectors on the market under different climatic and demand conditions.

  9. Current collector design for closed-plenum polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Daniels, F. A.; Attingre, C.; Kucernak, A. R.; Brett, D. J. L.

    2014-03-01

    This work presents a non-isothermal, single-phase, three-dimensional model of the effects of current collector geometry in a 5 cm2 closed-plenum polymer electrolyte membrane (PEM) fuel cell constructed using printed circuit boards (PCBs). Two geometries were considered in this study: parallel slot and circular hole designs. A computational fluid dynamics (CFD) package was used to account for species, momentum, charge and membrane water distribution within the cell for each design. The model shows that the cell can reach high current densities in the range of 0.8 A cm-2-1.2 A cm-2 at 0.45 V for both designs. The results indicate that the transport phenomena are significantly governed by the flow field plate design. A sensitivity analysis on the channel opening ratio shows that the parallel slot design with a 50% opening ratio shows the most promising performance due to better species, heat and charge distribution. Modelling and experimental analysis confirm that flooding inhibits performance, but the risk can be minimised by reducing the relative humidity of the cathode feed to 50%. Moreover, overheating is a potential problem due to the insulating effect of the PCB base layer and as such strategies should be implemented to combat its adverse effects.

  10. Suppression of Plesiomonas shigelloides growth in the Direct Plating method for the enumeration of Escherichia coli in water

    NARCIS (Netherlands)

    Schets FM; List C; Kadar M; de Ruiter H; Medema GJ; MGB; Water Storage Corporation Brabantse Biesbosch; Werkendam; National Institute of Hygiene; Budapest; RIZA; Lelystad

    1998-01-01

    Plesiomonas shigelloides bleek vals positieve reacties te veroorzaken in de Escherichia coli Direct Plating (DP) methode. In het hier beschreven onderzoek is geprobeerd de groei van Plesiomonas te onderdrukken door toevoeging van het vibriostaticum O/129

  11. Towards the optimization of the thermal–hydraulic performance of gyrotron collectors

    Energy Technology Data Exchange (ETDEWEB)

    Savoldi, Laura; Bertani, Cristina [Dipartimento Energia, Politecnico di Torino, 10129 Torino (Italy); Cau, Francesca; Cismondi, Fabio [F4E, Barcelona (Spain); Gantenbein, Gerd; Illy, Stefan [Karlsruhe Institute of Technology (KIT), Institute for Pulsed Power and Microwave Technology (IHM), Kaiserstr. 12, 76131 Karlsruhe (Germany); Monni, Grazia [Dipartimento Energia, Politecnico di Torino, 10129 Torino (Italy); Rozier, Yoann [Thales Electron Devices, 78141 Vélizy-Villacoublay (France); Zanino, Roberto, E-mail: roberto.zanino@polito.it [Dipartimento Energia, Politecnico di Torino, 10129 Torino (Italy)

    2015-11-15

    Different configurations of water-cooled Cu collector for gyrotrons are investigated using the StarCCM + CFD code, aimed at optimizing its thermal–hydraulic (TH) performance. Although the current collectors show a good performance, the collector can be subjected to transient heat loads, due to the spent electron beam, of up to several tens of MW/m{sup 2}, and there is an interest to increase the gyrotron output power in the future. Furthermore, an optimized cooling will lead to improved reliability and lifetime of the collector. Starting from a hypervapotron (HV)-like collector, characterized by 100+ deep rectangular cavities with aspect ratio (AR) = 3, we present in the first part of the paper a single-cavity steady-state parametric analysis of the effect of AR on the heat exhaust capabilities. The investigation is then extended to other collector designs, including circumferential ribs and dimples, in order to assess the options for further improvements of the TH performance. The peak Cu temperature is computed by the code and its minimization is the target of the present optimization exercise. A self-consistent estimate of the heat transfer coefficient between collector and coolant is also obtained, which could be useful for fatigue and lifetime assessments. In the second part of the paper the most promising collector geometries identified in the first part are analyzed in the case of a transient heat load (vertical sweeping), first at the level of a single spatial period of the collector structure, then at the full-collector level. The results of the TH transient analysis are compared with both the results of the first part and with the transient purely thermal analysis of the full collector, showing for all geometries considered in this study a room for cooling efficiency improvement with respect to the HV-like design with AR = 3, at least in the operating conditions considered for this study (V ∼ 4 m/s, almost 100 °C sub-cooling).

  12. Solar energy collector/storage system

    Energy Technology Data Exchange (ETDEWEB)

    Bettis, J.R.; Clearman, F.R.

    1983-05-24

    A solar energy collector/storage system which includes an insulated container having working fluid inlets and outlets and an opening, a light-transmitting member positioned over the opening, and a heat-absorbing member which is centrally situated, is supported in the container, and is made of a mixture of gypsum , lampblack, and water. A light-reflecting liner made of corrugated metal foil preferably is attached to the internal surface of the container. The opening of the container is positioned in optical alignment with a source of solar energy. A light-reflecting cover optionally can be hingedly attached to the container, and can be positioned such as to reflect solar energy rays into the container. The system is adaptable for use with a working gas (e.g., air) and/or a working liquid (e.g., water) in separated flows which absorb heat from the heat-absorbing member, and which are useable per se or in an associated storage and/or circulatory system that is not part of this invention. The heatabsorbing mixture can also contain glass fibers. The heatabsorbing member is of such great load-bearing strength that it can also be used simultaneously as a structural member, e.g., a wall or ceiling of a room; and, thereby, the system can be used to heat a room, if a window of the room is the light-transmitting member and is facing the sun, and if the heat-absorbing member is a wall and/or the ceiling of the room and receives solar energy through the window.

  13. CISBAT 2007 - Solar collectors (heat and electricity)

    International Nuclear Information System (INIS)

    2007-01-01

    This is the third part of the proceedings of the 2007 CISBAT conference on Renewables in a changing climate, held in Lausanne, Switzerland. On the subject of Building and urban integration of renewables the following oral contributions are summarised: 'Facade integration of solar thermal collectors: present and future', 'Long term experiences with a versatile PV in roof system', 'Development of a design and performance prediction tool for the ground source heat pump and underground thermal storage system', 'Hygrothermal performance of earth-to-air heat exchanger: long-term data evaluation and short-term simulation' as well as 'The real cost of heating your home: a comparative assessment of home energy systems with external costs'. Poster-sessions on the subject include 'Central solar heating plants with seasonal heat storage', 'Analysis of forced convection for evaporative air flow and heat transfer in PV cooling channels', 'Renewable energy technology in Mali: constraints and options for a sustainable development', 'Effect of duct width in ducted photovoltaic facades', 'Design and actual measurement of a ground source heat pump system using steel foundation piles as ground heat exchangers', 'Development of an integrated water-water heat pump unit for low energy house and its application', 'PV effect in multilayer cells and blending of fullerene/poly (3-hexylthiophene) and phthalocyanine having NIR charge transfer absorption band', 'CdTe photovoltaic systems - an alternative energetic', 'Integration of renewable energy sources in a town, examples in Grenoble', 'A prospective analysis method for the conception of solar integration solutions in buildings' and 'Energy and aesthetic improvements for building integration of cost effective solar energy systems'. Further groups of presentations at the conference are reported on in separate database records. An index of authors completes the proceedings

  14. Critical heat flux analysis on change of plate temperature and cooling water flow rate for rectangular narrow gap with bilateral-heated cases

    International Nuclear Information System (INIS)

    M Hadi Kusuma; Mulya Juarsa; Anhar Riza Antariksawan

    2013-01-01

    Boiling heat transfer phenomena on rectangular narrow gap was related to the safety of nuclear reactors. Research done in order to study the safety of nuclear reactors in particular relating to boiling heat transfer and useful on the improvement of next-generation reactor designs. The research focused on calculation of the heat flux during the cooling process in rectangular narrow gap size 1.0 mm. with initial temperatures 200°C. 400°C, and 600°C, also the flow rates of cooling water 0,1 liters/second. 0,2 liters/second. and 0,3 liters/second. Experiments carried out by injecting water at a certain flow rate with the water temperature 85°C. Transient temperature measurement data recorded by the data acquisition system. Transient temperature measurement data is used to calculate the flux of heat gain is then used to obtain the heat transfer coefficient. This research aimed to obtain the correlation between critical heat flux and heat transfer coefficient to changes in temperatures and water flow rates for bilaterally-heated cases on rectangular narrow gap. The results obtained for a constant cooling water flow rate, critical heat flux will increase when hot plate temperature also increased. While on a constant hot plate temperature, coefficient heat transfer will increase when cooling water flow rate also increased. Thus it can be said that the cooling water flow rate and temperature of the hot plate has a significant effect on the critical heat flux and heat transfer coefficient resulted in quenching process of vertical rectangular narrow gap with double-heated cases. (author)

  15. Oil/gas collector/separator for underwater oil leaks

    Energy Technology Data Exchange (ETDEWEB)

    Henning, C.D.

    1992-12-31

    This invention is comprised of an oil/gas collector/separator for recovery of oil leaking, for example, from an offshore or underwater oil well. The separator is floated over the point of the leak and tethered in place so as to receive oil/gas floating, or forced under pressure, toward the water surface from either a broken or leaking oil well casing, line, or sunken ship. The separator is provided with a downwardly extending skirt to contain the oil/gas which floats or is forced upward into a dome wherein the gas is separated from the oil/water, with the gas being flared (burned) at the top of the dome, and the oil is separated from water and pumped to a point of use. Since the density of oil is less than that of water it can be easily separated from any water entering the dome.

  16. Investigating the collector efficiency of silver nanofluids based direct absorption solar collectors

    International Nuclear Information System (INIS)

    Chen, Meijie; He, Yurong; Zhu, Jiaqi; Wen, Dongsheng

    2016-01-01

    Highlights: • An analysis coupled with Radiation transfer, Maxwell and Energy equation is developed. • Plasmonic Au and Ag nanofluids show better photo-thermal conversion properties. • Collector height and particle concentration exist optimum solutions for efficiency. - Abstract: A one-dimensional transient heat transfer analysis was carried out to analyze the effects of the Nanoparticle (NP) volume fraction, collector height, irradiation time, solar flux, and NP material on the collector efficiency. The numerical results were compared with the experimental results obtained by silver nanofluids to validate the model, and good agreement was obtained. The numerical results show that the collector efficiency increases as the collector height and NP volume fraction increase and then reaches a maximum value. An optimum collector height (∼10 mm) and particle concentration (∼0.03%) achieving a collector efficiency of 90% of the maximum efficiency can be obtained under the conditions used in the simulation. However, the collector efficiency decreases as the irradiation time increases owing to the increased heat loss. A high solar flux is desirable to maintain a high efficiency over a wide temperature range, which is beneficial for subsequent energy utilization. The modeling results also show silver and gold nanofluids obtain higher photothermal conversion efficiencies than the titanium dioxide nanofluid because their absorption spectra are similar to the solar radiation spectrum.

  17. Two new designs of parabolic solar collectors

    Directory of Open Access Journals (Sweden)

    Karimi Sadaghiyani Omid

    2014-01-01

    Full Text Available In this work, two new compound parabolic trough and dish solar collectors are presented with their working principles. First, the curves of mirrors are defined and the mathematical formulation as one analytical method is used to trace the sun rays and recognize the focus point. As a result of the ray tracing, the distribution of heat flux around the inner wall can be reached. Next, the heat fluxes are calculated versus several absorption coefficients. These heat flux distributions around absorber tube are functions of angle in polar coordinate system. Considering, the achieved heat flux distribution are used as a thermal boundary condition. After that, Finite Volume Methods (FVM are applied for simulation of absorber tube. The validation of solving method is done by comparing with Dudley's results at Sandia National Research Laboratory. Also, in order to have a good comparison between LS-2 and two new designed collectors, some of their parameters are considered equal with together. These parameters are consist of: the aperture area, the measures of tube geometry, the thermal properties of absorber tube, the working fluid, the solar radiation intensity and the mass flow rate of LS-2 collector are applied for simulation of the new presented collectors. After the validation of the used numerical models, this method is applied to simulation of the new designed models. Finally, the outlet results of new designed collector are compared with LS-2 classic collector. Obviously, the obtained results from the comparison show the improving of the new designed parabolic collectors efficiency. In the best case-study, the improving of efficiency are about 10% and 20% for linear and convoluted models respectively.

  18. Effect of plate shapes in orifice plate type flowmeters

    International Nuclear Information System (INIS)

    Moeller, S.V.

    1984-01-01

    The study of unusual plate shapes in orifice plate type flowmeters is presented, with a view to providing data for the substitution of the plate with one centered circular orifice in those applications where its use is not possible. For this purpose, six pairs of plates with different forms, with and without chamfered edges, were made and tested in a closed water loop. Results show that, generally, the use of chamfers improves the results and, in the case of perforated and slotlike orificed plates, the narrow-ness of the fluid passage tends to make unnecessary its use. (Author) [pt

  19. System Design Package for SIMS Prototype System 3, Solar Heating and Domestic Hot Water

    Science.gov (United States)

    1978-01-01

    A collation of documents and drawings are presented that describe a prototype solar heating and hot water system using liquid flat plate collectors and a gas or electric furnace energy subsystem. The system was designed for installation into a single-family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system are packaged for evaluation of the system with information sufficient to assemble a similar system.

  20. Efficiency of the Fermilab Electron Cooler's Collector

    CERN Document Server

    Prost, L R

    2005-01-01

    The newly installed high-energy Recycler Electron Cooling system (REC) at Fermilab will work at an electron energy of 4.34 MeV and a DC beam current of 0.5 A in an energy recovery scheme. For reliable operation of the system, the relative beam current loss must be maintained to levels < 3.e-5. Experiments have shown that the loss is determined by the performance of the electron beam collector, which must retain secondary electrons generated by the primary beam hitting its walls. As a part of the Electron cooling project, the efficiency of the collector for the REC was optimized, both with dedicated test bench experiments and on two versions of the cooler prototype. We find that to achieve the required relative current loss, an axially-symmetric collector must be immersed in a transverse magnetic field with certain strength and gradient prescriptions. Collector efficiencies in various magnetic field configurations, including without a transverse field on the collector, are presented and discussed

  1. Tube collector with integrated tracking parabolic concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Grass, C.; Benz, N.; Hacker, Z.; Timinger, A. [ZAE Bayern, Bavarian Centre for Applied Energy Research, Muenchen (Germany)

    2000-07-01

    Low concentrating CPC collectors usually do not track the sun and are mounted in east-west direction with a latitude dependent slope angle. They are most suitable for maximum working temperatures up to 200 250 deg. C. We present a novel evacuated tube-collector with a trough-like concentrating mirror. Single-axis tracking of the mirror is realized with a magnetic mechanism. The mirror is mounted inside the evacuated tube and hence protected from environmental influences. One axis tracking in combination with a small acceptance angle allows for higher concentration as compared to non-tracking concentrating collectors. Ray-tracing analysis shows a half acceptance angle of about 5 deg. at a geometrical concentration ratio of 3.2. The losses of evacuated tube collectors are dominated by the radiation losses of the absorber. Hence, reducing the absorber size can lead to higher efficiencies at high operating temperature levels. With the presented collector we aim for operating temperatures up to 400 deg. C. At temperatures of 300 deg. C we expect efficiencies of 65 %. This allows for application in industrial process heat generation, high efficient solar cooling and power generation. A first prototype was tested at the ZAE Bayern. The optical efficiency was measured to be 75 %. (au)

  2. Studi Kinerja Solar Water Heater Dengan Aliran Zig-zag Beralur Balok

    Directory of Open Access Journals (Sweden)

    M. Rizki Ikhsan

    2017-05-01

    Full Text Available Solar energy can be used for water heating by using solar water heater application. Therefore, its still needs some modification due to its low efficiency. This modification can be done by replacing the conventional plate of solar collectors into a double plate with a zig-zag pattern. The results shown that along with the decreasing of water flow rates could significantly increase the useful energy (Qu. Initial temperature of water inlet could affect the generated maximum temperature. The highest mean efficiencies of double plate solar water heater with a zig-zag grooved beams pattern of 49.11% was gained in the flow rate of 700 mL / min.

  3. A solar collector for air-conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kose, E. [Microtherm Energietechnik GmbH, 25 - Lods (France)

    1999-03-01

    A high performance Compound Parabolic Concentrator (CPC) collector is presented. It comprises dewar type tubular vacuum tubes with an absorber coating of very low emittance, a moderately concentrating reflector and a simple thermosyphon heat removal system. The reflectors car be designed with respect to the specific needs; reflector material, concentration, truncation and symmetry car be chosen freely. The collector allows the construction of cooling systems with higher COP's without using tracking systems. Land use and costs are greatly reduced. For a certain application (optimum yearly gain in Munich with a constant collector temperature of 180 deg C) the reflector was optimized, it is a fairly asymmetrical design. A symmetrical design with a similar performance has been tested, the results are shown. (author)

  4. Optimum solar collector fluid flow rates

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    1996-01-01

    Experiments showed that by means of a standard electronically controlled pump, type UPE 2000 from Grundfos it is possible to control the flow rate in a solar collector loop in such a way that the flow rate is strongly influenced by the temperature of the solar collector fluid passing the pump....... The flow rate is increasing for increasing temperature.The flow rate at the high temperature level is typically 70 % greater than the flow rate at the low temperature level.Further, the energy consumption for the electronically controlled pump in a solar heating system will be somewhat smaller than...... the energy consumption of a normal ciculation pump in the solar heating system.Calculations showed that the highest thermal performances for small SDHW systems based on mantle tanks with constant volume flow rates in the solar collector loops are achieved if the flow rate is situated in the interval from 0...

  5. Adsorption of guanidinium collectors on aluminosilicate minerals - a density functional study.

    Science.gov (United States)

    Nulakani, Naga Venkateswara Rao; Baskar, Prathab; Patra, Abhay Shankar; Subramanian, Venkatesan

    2015-10-07

    In this density functional theory based investigation, we have modelled and studied the adsorption behaviour of guanidinium cations and substituted (phenyl, methoxy phenyl, nitro phenyl and di-nitro phenyl) guanidinium cationic collectors on the basal surfaces of kaolinite and goethite. The adsorption behaviour is assessed in three different media, such as gas, explicit water and pH medium, to understand the affinity of GC collectors to the SiO4 tetrahedral and AlO6 octahedral surfaces of kaolinite. The tetrahedral siloxane surface possesses a larger binding affinity to GC collectors than the octahedral sites due to the presence of surface exposed oxygen atoms that are active in the intermolecular interactions. Furthermore, the inductive electronic effects of substituted guanidinium cations also play a key role in the adsorption mechanism. Highly positive cations result in a stronger electrostatic interaction and preferential adsorption with the kaolinite surfaces than low positive cations. Computed interaction energies and electron densities at the bond critical points suggest that the adsorption of guanidinium cations on the surfaces of kaolinite and goethite is due to the formation of intra/inter hydrogen bonding networks. Also, the electrostatic interaction favours the high adsorption ability of GC collectors in the pH medium than gas phase and water medium. The structures and energies of GC collectors pave an intuitive view for future experimental studies on mineral flotation.

  6. Impact of pressure losses in small-sized parabolic-trough collectors for direct steam generation

    International Nuclear Information System (INIS)

    Lobón, David H.; Valenzuela, Loreto

    2013-01-01

    Using PTC (parabolic-trough solar collectors) for industrial thermal processes in the temperature range up to 300 °C is not new, but in recent years there is a boosted interest in this type of concentrating solar technology. One of the problems that arise when designing PTC solar fields is how to deal with the pressure losses which are critical when producing saturated steam directly in the collectors. Depending on the characteristics of the collector, mainly on the receiver diameter, and on the nominal process conditions defined, a solar field configuration can be feasible or not. This paper presents a sensitivity analysis done using a software tool developed to study the thermo-hydraulic behaviour of PTC systems using water-steam as heat transfer fluid. In the case study presented, a small-sized PTC designed for industrial process heat applications is considered, which has a focal length of 0.2 m, an aperture area of 2 m 2 , and its receiver pipe has an inner diameter of 15 mm. Varied process conditions are inlet water pressure, temperature, and mass flow rate, solar irradiance and incidence angle of solar radiation. Results show that working pressure definition is particularly critical to make feasible or not the direct steam generation in solar collectors. - Highlights: • DSG (Direct steam generation) in small-sized parabolic-trough collectors. • Thermo-hydraulic sensitivity analysis. • Influence of working pressure and receiver geometry in DSG process

  7. Development and calibration of a ground-based active collector for cloud- and fogwater

    Energy Technology Data Exchange (ETDEWEB)

    Kins, L.; Junkermann, W.; Meixner, F.X.; Muller, K.P.; Ehhalt, D.H.

    1986-04-01

    In spring 1985, field experiments were started to study the scavenging processes of atmospheric trace substances. Besides the chemical analysis of precipitation sample, these studies required simultaneous collection of cloud water for chemical analysis. In particular, a ground-based cloud water collector was needed, suitable for use on the top of a TV-tower. Existing designs of ground-based cloud or fogwater samplers be divided into two general classes: a) passive collectors, which utilize the ambient wind to impact the droplets on the collection surface; b) active collectors, which accelerate the droplets to a certain velocity as they approach the collection surface. Teflon-strings are extended between two disks which are 1m apart. The disadvantage of this collector, for these experiments, was that the collector strings are always exposed to the ambient air, so that contamination by aerosol impact during dry periods can not be excluded. Furthermore, because of the length of the strings, impacted droplets need a certain time to drain off, during which they remain exposed to the ambient air stream and continue to scavenge trace gases.

  8. Hierarchical Surface Architecture of Plants as an Inspiration for Biomimetic Fog Collectors.

    Science.gov (United States)

    Azad, M A K; Barthlott, W; Koch, K

    2015-12-08

    Fog collectors can enable us to alleviate the water crisis in certain arid regions of the world. A continuous fog-collection cycle consisting of a persistent capture of fog droplets and their fast transport to the target is a prerequisite for developing an efficient fog collector. In regard to this topic, a biological superior design has been found in the hierarchical surface architecture of barley (Hordeum vulgare) awns. We demonstrate here the highly wettable (advancing contact angle 16° ± 2.7 and receding contact angle 9° ± 2.6) barbed (barb = conical structure) awn as a model to develop optimized fog collectors with a high fog-capturing capability, an effective water transport, and above all an efficient fog collection. We compare the fog-collection efficiency of the model sample with other plant samples naturally grown in foggy habitats that are supposed to be very efficient fog collectors. The model sample, consisting of dry hydrophilized awns (DH awns), is found to be about twice as efficient (fog-collection rate 563.7 ± 23.2 μg/cm(2) over 10 min) as any other samples investigated under controlled experimental conditions. Finally, a design based on the hierarchical surface architecture of the model sample is proposed for the development of optimized biomimetic fog collectors.

  9. The effect of using nano-silver dispersed water based nanofluid as a passive method for energy efficiency enhancement in a plate heat exchanger

    International Nuclear Information System (INIS)

    Behrangzade, Ali; Heyhat, Mohammad Mahdi

    2016-01-01

    Highlights: • The effect of using nano-silver on a commercial plate heat exchanger was studied. • An experimental rig was designed to investigate the thermo-hydrodynamic features of nanofluid. • The overall heat transfer coefficient becomes larger 16.79% for 100 ppm nanofluid. • No significant growth in pressure drop values was observed. • The process temperatures have important role in nanofluid influence. - Abstract: The purpose of this study is to verify the potential using of nano-silver dispersed water based nanofluid on efficiency improvement of a commercial corrugated plate heat exchanger. In this regards, an experimental rig was provided to recognize the heat transfer rate and pressure drop of Ag–water nanofluid as the working fluid. The two most key thermo-physical properties, i.e. dynamic viscosity and thermal conductivity of nanofluids were experimentally gauged. The findings, which were achieved, displayed that the overall heat transfer coefficient becomes larger, from 6.18% to 16.79%, for 100 ppm silver nanofluid. While using nanofluid, no significant growth in pressure drop values was observed. Moreover, the process temperatures and flow rates have significant impacts on the helpfulness of applying nanofluid in a plate heat exchanger.

  10. A stationary evacuated collector with integrated concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Snail, K.A.; O' Gallagher, J.J.; Winston, R.

    1984-01-01

    A comprehensive set of experimental tests and detailed optical and thermal models are presented for a newly developed solar thermal collector. The new collector has an optical efficiency of 65 per cent and achieves thermal efficiencies of better than 50 per cent at fluid temperatures of 200/sup 0/C without tracking the sun. The simultaneous features of high temperature operation and a fully stationary mount are made possible by combining vacuum insulation, spectrally selective coatings, and nonimaging concentration in a novel way. These 3 design elements are ''integrated'' together in a self containe unit by shaping the outer glass envelope of a conventional evacuated tube into the profile of a nonimaging CPC-type concentrator. This permits the use of a first surface mirror and eliminates the need for second cover glazing. The new collector has been given the name ''Integrated Stationary Evacuated Concentrator'', or ISEC collector. Not only is the peak thermal efficiency of the ISEC comparable to that of commercial tracking parabolic troughs, but projections of the average yearly energy delivery also show competitive performance with a net gain for temperatures below 200/sup 0/C. In addition, the ISEC is less subject to exposure induced degradation and could be mass produced with assembly methods similar to those used with fluorescent lamps. Since no tracking or tilt adjustments are ever required and because its sensitive optical surfaces are protected from the environment, the ISEC collector provides a simple, easily maintained solar thermal collector for the range 100-300/sup 0/C which is suitable for most climates and atmospheric conditions. Potential applications include space heating, air conditioning, and industrial process heat.

  11. Waffle production: influence of batter ingredients on sticking of waffles at baking plates-Part II: effect of fat, leavening agent, and water.

    Science.gov (United States)

    Huber, Regina; Schoenlechner, Regine

    2017-05-01

    Fresh egg waffles are continuously baked in tunnel baking ovens in industrial scale. Waffles that partly or fully stick to the baking plates cause significant product loss and increased costs. The aim of this study was, therefore, to investigate the effect of different recipe ingredients on the sticking behavior of waffles. In this second part, ingredients investigated were different leavening agents (sodium acid pyrophosphate, ammonium bicarbonate, magnesium hydroxide carbonate, or monocalcium phosphate), different fat sources (rapeseed oil, cocos fat, butter, or margarine), and different water sources (tap water 12°dH and distilled water). Within the different types of fats, solid fats with high amount of short-chain fatty acids (cocos fat or butter) decreased the number of sticking waffles compared to liquid oils (rapeseed oil). Regarding leavening agents, magnesium hydroxide carbonate and ammonium bicarbonate were superior to sodium acid pyrophosphate or monocalcium phosphate. Between the two water sources, effects were small.

  12. Thermal characteristics and performance of Ag-water nanofluid: Application to natural circulation loops

    International Nuclear Information System (INIS)

    Koca, Halil Dogacan; Doganay, Serkan; Turgut, Alpaslan

    2017-01-01

    Highlights: • Thermal conductivity and viscosity of Ag-water nanofluid were measured. • Thermal performance of Ag-water nanofluid was compared with water. • Effectiveness enhanced up to 11% with 1 wt% Ag-water nanofluid. • Effectiveness of Ag-water nanofluid samples increased with inclination angle. • Ag-water nanofluid has potential to be used in flat-plate solar collectors. - Abstract: The goal of this study is to investigate the thermal conductivity, viscosity and thermal performance in a single-phase natural circulation mini loop of Ag-water nanofluid which can be a potential working fluid for natural convective flat-plate solar collectors. The silver-water nanofluid with 5 wt% concentration, which contains also polyvinylpyrrolidone (PVP) with 1.25 wt%, was purchased. Then, the sample was diluted with de-ionized water to four different concentrations of 0.25, 0.5, 0.75 and 1 wt%. Thermal conductivity and viscosity were measured by 3ω method and Brookfield rheometer, respectively. An effectiveness factor was used to define the thermal performance of Ag-water nanofluids for different inclination angles and heating powers. The results showed that nanofluid samples are thermally less conductive than the literature, at ambient temperature (23 °C). The viscosity of nanofluid decreases significantly with increasing temperature and increases with increasing concentration. Our measurements appear to be more compatible with PVP solution results available in the literature. Effectiveness is enhanced up to 11% with 1 wt% concentrated nanofluid compared to de-ionized water and the effectiveness of the mini loop indicates an enhancement with increase in inclination angle and particle concentration at whole applied power. According to obtained results, it is concluded that Ag-water nanofluid has a promising potential to be used in natural convective flat-plate solar collector.

  13. Photocatalytic degradation of dissolved organic matter in the ground water employing TiO2 film supported on stainless steel plate

    International Nuclear Information System (INIS)

    Andayani, W.; Sumartono, A.; Lindu, M.

    2012-01-01

    The Taman Palem Residences, Cengkareng, Indonesia has a groundwater problem as a main sources of drinking water in the area due to yellowish brown colour of the water, that may come from dissolved organic matter (DOM), humic substances. Photocatalytic degradation using TiO 2 coated on a stainless steel plate (8 x 8 cm) to degrade the dissolved organic matter was studied. Groundwater samples were collected at 150 m deep from Taman Palem Residences. The TiO 2 catalyst was made from deep coating in a sol-gel system of titanium (IV) diisopropoxidebisacetylacetonate (TAA) precursor and immobilized at stainless steel plate (8 x 8 cm), followed by calcination at 525°C. Two catalyst sheets were put in batch reactor containing groundwater. The ground water containing DOM were irradiated by UV black light at varying initial pH values i.e 5, 7 and 9. Sampling of solution was taken at the interval time of 0, 1, 2, 4, and 6 hours. DOM residu in water before and after irradiation were measured by spectrophotometer UV-Vis at 300 nm. Photocatalytic degradation of DOM was greater in acid solution than in basic solution. The determination of intermediate degradation products by HPLC revealed that oxalic acid was detected consistently. (author)

  14. Multi criteria sizing approach for Photovoltaic Thermal collectors supplying desalination plant

    International Nuclear Information System (INIS)

    Ammous, Mahmoud; Chaabene, Maher

    2015-01-01

    Highlights: • Concept of reverse osmosis desalination plant supplied by hybrid collectors. • Energy consumption optimization. • Plant modeling. • Sizing approach for a desalination plant supplied by hybrid collectors. - Abstract: Reverse osmosis desalination plants require both thermal and electrical energies in order to produce water. As Photovoltaic Thermal panels are able to provide the two energies, they become suitable to supply reverse osmosis plants mainly while installed in remote areas. Autonomous based desalination plants must be optimally sized to meet the criteria related to the reverse osmosis operating temperature, the plant autonomy, the needed water, etc. This paper presents a sizing approach for Photovoltaic Thermal collectors supplying reverse osmosis desalination plant to compute the optimal surface of Photovoltaic Thermal collectors and the tank volume with respect to the operating criteria. The approach is composed of three optimization consideration steps: the monthly average data, the fulfillment of the water need and a three day of autonomy for the water tank volume. The algorithm is tested for a case of study of 10 ha of tomato irrigation. The results converged to 700 m 2 of Photovoltaic Thermal collector’s surface and 3000 m 3 of water tank volume

  15. A Study on Thermal Performance of a Novel All-Glass Evacuated Tube Solar Collector Manifold Header with an Inserted Tube

    Directory of Open Access Journals (Sweden)

    Jichun Yang

    2015-01-01

    Full Text Available A novel all-glass evacuated tube collector manifold header with an inserted tube is proposed in this paper which makes water in all-glass evacuated solar collector tube be forced circulated to improve the performance of solar collector. And a dynamic numerical model was presented for the novel all-glass evacuated tube collector manifold header water heater system. Also, a test rig was built for model validation and comparison with traditional all-glass evacuated tube collector. The experiment results show that the efficiency of solar water heater with a novel collector manifold header is higher than traditional all-glass evacuated tube collector by about 5% and the heat transfer model of water heater system is valid. Based on the model, the relationship between the average temperature of water tank and inserted tube diameter (water mass flow has been studied. The results show that the optimized diameter of inserted tube is 32 mm for the inner glass with the diameter of 47 mm and the water flow mass should be less than 1.6 Kg/s.

  16. Behavior of a solar collector loop during stagnation

    DEFF Research Database (Denmark)

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon

    2015-01-01

    A mathematical model simulating the emptying behavior of a pressurized solar collector loop with solar collectors with a good emptying behavior is developed and validated with measured data. The calculated results are in good agreement with the measured results. The developed simulation model...... is therefore suitable to determine the behavior of a solar collector loop during stagnation. A volume ratio R, which is the ratio of the volume of the vapour in the upper pipes of the solar collector loop during stagnation and the fluid content of solar collectors, is introduced to determine the mass...... of the collector fluid pushed into the expansion vessel during stagnation, Min. A correlation function for the mass Min and the volume ratio R for solar collector loops is obtained. The function can be used to determine a suitable size of expansion vessels for solar collector loops....

  17. Two-axis movable concentrating solar energy collector

    Science.gov (United States)

    Perkins, G. S.

    1977-01-01

    Proposed solar-tracker collector assembly with boiler in fixed position, allows use of hard line connections, capable of withstanding optimum high temperature fluid flow. System thereby eliminates need for flexible or slip connection previously used with solar collector systems.

  18. Solar Water Heater Installation Package

    Science.gov (United States)

    1982-01-01

    A 48-page report describes water-heating system, installation (covering collector orientation, mounting, plumbing and wiring), operating instructions and maintenance procedures. Commercial solar-powered water heater system consists of a solar collector, solar-heated-water tank, electrically heated water tank and controls. Analysis of possible hazards from pressure, electricity, toxicity, flammability, gas, hot water and steam are also included.

  19. A tool for standardized collector performance calculations including PVT

    DEFF Research Database (Denmark)

    Perers, Bengt; Kovacs, Peter; Olsson, Marcus

    2012-01-01

    A tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute of Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance of solar collectors at representative locations...... can be tested and modeled as a thermal collector, when the PV electric part is active with an MPP tracker in operation. The thermal collector parameters from this operation mode are used for the PVT calculations....

  20. Local Reasoning about a Copying Garbage Collector

    DEFF Research Database (Denmark)

    Torp-Smith, Noah; Birkedal, Lars; Reynolds, John C.

    2008-01-01

    We present a programming language, model, and logic appropriate for implementing and reasoning about a memory management system. We state semantically what is meant by correctness of a copying garbage collector, and employ a variant of the novel separation logics to formally specify partial corre...

  1. 31 CFR 203.17 - Collector depositaries.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collector depositaries. 203.17 Section 203.17 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE PAYMENT OF FEDERAL TAXES AND THE TREASURY...

  2. Copyright, Property and the Film Collector

    Science.gov (United States)

    Nevins, Francis M., Jr.

    1975-01-01

    Legal issues surrounding the collecting of movies are analyzed with the conclusion that neither law nor public policy supports a cause for action against the ultimate consumer of film prints and that it is not in a studio's economic interest to bring such actions against collectors. (JT)

  3. Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas

    Science.gov (United States)

    1980-01-01

    A solar heating system designed to supply a major portion of the space and water heating requirements for a restaurant is described. The restaurant has a floor space of approximately 4,650 square feet and requires approximate 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10 to the 6th power Btu/Yr (specified) building heating and hot water heating.

  4. Colored solar collectors - Annual report 2006

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, A.; Chambrier, E. De; Roecker, Ch.; Scartezzini, J.-L.

    2007-12-15

    The architectural integration of thermal solar collectors into buildings is often limited by their black color, and the visibility of tubes and corrugations of the absorber sheets. A certain freedom in color choice would be desirable, but the colored appearance should not cause an excessive degradation of the collector efficiency. Multilayered thin film interference filters on the collector glazing can produce a colored reflection, hiding the corrugated metal sheet, while transmitting the non-reflected radiation entirely to the absorber. These interference filters are designed and optimized by numerical simulation, and are manufactured by sol-gel dip-coating or magnetron sputtering. The novel colored glazed solar collectors will be ideally suited for architectural integration into buildings, e.g. as solar active glass facades. Due to the tunability of the refractive index, nanostructured materials such as SiO{sub 2}:TiO{sub 2} composites and porous SiO{sub 2} are very useful for application in multilayer interference stacks. Novel quaternary Mg-F-Si-O films exhibit a surprisingly low refractive index and are therefore promising candidates for highly transparent coatings on solar collector glazing. The nanostructure of these thin films is studied by transmission electron microscopy, while the optical constants are measured precisely by ellipsometry. For a convincing demonstration, sufficiently large samples of high quality are imperatively needed. The fabrication of nanocomposite SiO{sub 2}:TiO{sub 2} films has been demonstrated by sol-gel dip-coating of A4-sized glass panes. The produced coatings exhibit a colored reflection in combination with a high solar transmittance, a homogenous appearance, and are free of visible defects. Film hardening by UV exposure will result in speeding up the sol-gel process and saving energy, thereby reducing costs significantly. The infrastructure for UV-curing has been established. A UV C radiation source can now be attached to the

  5. Low cost thermal solar collector

    International Nuclear Information System (INIS)

    Abugderah, M. M.; Schneider, E. L.; Tontini, M. V.

    2006-01-01

    Solar energy is a good alternative in the economy of the electric energy mainly for the water heating. However, the solar heaters used demand a high initial investment, becoming the warm water from solar energy inaccessible to a large part of the society. Thus, a low cost solar heater was developed, constructed and tested in the chemical engineering department of West Parana State University-Unioeste. This equipment consists of 300 cans, divided in 30 columns of 10 cans each, all painted in black to enhance the obsorption of the solar radiation. The columns are connected to a pipe of pvc of 8 liters with 0.085m of external diameter. The equipment is capable to heat 120 liters of water in temperatures around 60 degree centigrade. The heater is insolated in its inferior part with cardboard and aluminum, covered with a transparent plastic in its superior. The system still counts with a insulated thermal reservoir, which can conserve the water in temperatures adjusted for the night non-solar days domestic use. The advantage of the constructed is it low cost material. The results are given an graphical tabular from showing acceptable efficiencies.(Autho

  6. Collector Efficiency in Downward-Type Double-Pass Solar Air Heaters with Attached Fins and Operated by External Recycle

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2012-07-01

    Full Text Available The collector efficiency in a downward-type double-pass external-recycle solar air heater with fins attached on the absorbing plate has been investigated theoretically. Considerable improvement in collector efficiency is obtainable if the collector is equipped with fins and the operation is carried out with an external recycle. Due to the recycling, the desirable effect of increasing the heat transfer coefficient compensates for the undesirable effect of decreasing the driving force (temperature difference of heat transfer, while the attached fins provide an enlarged heat transfer area. The order of performances in the devices of same size is: double pass with recycle and fins > double pass with recycle but without fins > single pass without recycle and fins.

  7. A novel design for a cheap high temperature solar collector: The rotating solar boiler

    NARCIS (Netherlands)

    Luijtelaer, van J.P.H.; Kroon, M.C.

    2009-01-01

    In this work a novel type of high temperature solar collector is designed: the rotating solar boiler. This rotating solar boiler consists of two concentric tubes. The inner tube, called absorber, absorbs sunlight and boils water. The outer transparent tube, called cover, is filled with air. The

  8. Bipolar Plates for PEM Systems

    OpenAIRE

    Lædre, Sigrid

    2016-01-01

    Summary of thesis: The Bipolar Plate (BPP) is an important component in both Proton Exchange Membrane Fuel Cells (PEMFCs) and Proton Exchange Membrane Water Electrolyzers (PEMWEs). Bipolar plate material and processing constitutes for a large fraction of the cost and weight of a PEM cell stack. The main tasks for the bipolar plates in both systems are to separate single cell in a stack, conduct current between single cells and remove heat from active areas. In addition, the BPPs distribu...

  9. Study of the influence of water properties dependency with the temperature in a laminar downward flow between parallel flat plates

    International Nuclear Information System (INIS)

    Delmastro, Dario F.; Chasseur, A.F.; Garcia, Juan C.

    2007-01-01

    In this work we develop a model that contemplates stationary completely developed laminar downward flow between flat parallel plates with uniform and constant heat fluxes. The Boussinesq approach is used in the momentum equation, taking into account the change of the density with the temperature only in the gravitational term. The system is at atmospheric pressure and the dependencies of the density and the thermal conductivity with the temperature are also considered. The velocity and temperature profiles, the friction factor, the heat transfer coefficient and the Nusselt Number are calculated, for different flow rates and heating powers. The results allow to obtain some conclusions that can be of interest in the study of research reactors with forced downward refrigeration and flat plate fuels, although these calculations do not exactly represent the real behavior inside these channels. (author) [es

  10. Experimental analysis of colloid capture by a cylindrical collector in laminar overland flow.

    Science.gov (United States)

    Wu, Lei; Gao, Bin; Muñoz-Carpena, Rafael

    2011-09-15

    Although colloid-facilitated contaminant transport in water flow is a well-known contamination process, little research has been conducted to investigate the transport of colloidal particles through emergent vegetation in overland flow. In this work, a series of laboratory experiments were conducted to measure the single-collector contact efficiency (η(0)) of colloid capture by a simulated plant stem in laminar lateral flow. Fluorescent microspheres of various sizes were used as experimental colloids. The colloid suspensions were applied to a glass cylinder installed in a small size flow chamber at different flow rates. Two cylinder sizes were tested in the experiment and silicone grease was applied to the cylinder surface to make it favorable for colloid deposition. Our results showed that increases in flow rate and collector size reduced the value of η(0) and a minimum value of η(0) might exist for a colloid size. The experimental data were compared to theoretical predictions of different single-collector contact efficiency models. The results indicated that existing single-collector contact efficiency models underestimated the η(0) of colloid capture by the cylinders in laminar overland flow. A regression equation of η(0) as a function of collector Reynolds number (Re(c)) and Peclet number (N(Pe)) was developed and fit the experimental data very well (R(2) > 0.98). This regression equation can be used to help construct and refine mathematical models of colloid transport and filtration in laminar overland flow on vegetated surfaces.

  11. Field Experiments of PV-Thermal Collectors for Residential Application in Bangkok

    Directory of Open Access Journals (Sweden)

    Atsushi Akisawa

    2012-04-01

    Full Text Available This study presents experimental results on Photovoltaic-thermal (PVT solar systems, the commercial photovoltaic (PV panels used as solar absorbers in PVT collectors, which are amorphous and multi-crystalline silicon. Testing was done with outdoor experiments in the climate of Bangkok corresponding to energy consumption behavior of medium size Thai families. The experimental results show that the thermal recovery of amorphous silicon PVT collector is almost the same as that of multi-crystalline silicon PVT collectors while electricity generation of multi crystalline silicon PVT is 1.2 times as much as that of amorphous silicon PVT. The maximum of heat gain from the PVT systems were obtained in March in summer. It was found that PVT collectors of unit area annually produced 1.1 × 103 kWh/m2 .year of heat and 55–83 kWh/m2.year of electricity, respectively. The results show that annual average solar factor of hot water supply is 0.45 for unit collector area. Economical evaluation based on energy costs in Thailand was conducted, which estimated the payback time would be 7 and 14 years for a-Si PVT and mc-Si PV, respectively.

  12. Performance simulation of serpentine type metallic and non-metallic solar collector

    International Nuclear Information System (INIS)

    Al-Sageer, A. A. M.; Alowa, M. I.; Saad, M.

    2006-01-01

    This paper presents a theoretical investigation of metallic and non-metalic solar water collector models for evaluating its performane parameters. The determined parameters include heat removal factor , overall heat loss coefficients, heat gain, daily and hourly efficiencies. The present study reports that, under forced circulation lest, the non-metallic collector has an inferior performance parameters when compared to that of the metallic one. It was also revealed that the overall heat loss coefficients of both collectors show weak dependence on the flow rate variations. It was also noticed that the heat removal factor forboth models is more sensitive to the flow rate variations. Also noticed that the heat removal factor for both models is more sensitive to the flow rate variations. Also, a comparision of performance parameters of the theoretical and experimental studies showed good agreements for most hours of the day, except the results obtained at the early morning and late after noon hours.(Author)

  13. Microelectrode generator-collector systems for electrolytic titration: theoretical and practical considerations.

    Science.gov (United States)

    Bell, Christopher G; Seelanan, Parinya; O'Hare, Danny

    2017-10-23

    Electochemical generator-collector systems, where one electrode is used to generate a reagent, have a potentially large field of application in sensing and measurement. We present a new theoretical description for coplanar microelectrode disc-disc systems where the collector is passive (such as a potentiometric sensor) and the generator is operating at constant flux. This solution is then used to develop a leading order solution for such a system where the reagent reacts reversibly in solution, such as in acid-base titration, where a hydrogen ion flux is generated by electrolysis of water. The principal novel result of the theory is that such devices are constrained by a maximum reagent flux. The hydrogen ion concentration at the collector will only reflect the buffer capacity of the bulk solution if this constraint is met. Both mathematical solutions are evaluated with several microfabricated devices and reasonable agreement with theory is demonstrated.

  14. Thermal Performance Analysis of Solar Collectors Installed for Combisystem in the Apartment Building

    Science.gov (United States)

    Žandeckis, A.; Timma, L.; Blumberga, D.; Rochas, C.; Rošā, M.

    2012-01-01

    The paper focuses on the application of wood pellet and solar combisystem for space heating and hot water preparation at apartment buildings under the climate of Northern Europe. A pilot project has been implemented in the city of Sigulda (N 57° 09.410 E 024° 52.194), Latvia. The system was designed and optimised using TRNSYS - a dynamic simulation tool. The pilot project was continuously monitored. To the analysis the heat transfer fluid flow rate and the influence of the inlet temperature on the performance of solar collectors were subjected. The thermal performance of a solar collector loop was studied using a direct method. A multiple regression analysis was carried out using STATGRAPHICS Centurion 16.1.15 with the aim to identify the operational and weather parameters of the system which cause the strongest influence on the collector's performance. The parameters to be used for the system's optimisation have been evaluated.

  15. On the Failure of Upscaling the Single-Collector Efficiency to the Transport of Colloids in an Array of Collectors

    Science.gov (United States)

    Messina, F.; Tosco, T.; Sethi, R.

    2017-12-01

    Colloidal transport and deposition in saturated porous media are phenomena of considerable importance in a large number of natural processes and engineering applications, such as the contaminant and microorganism propagation in aquifer systems, the development of innovative groundwater remediation technologies, air and water filtration, and many others. Therefore, a thorough understanding of particle filtration is essential for predicting the transport and fate of colloids in the subsurface environment. The removal efficiency of a filter is a key aspect for colloid transport in porous media. Several efforts were devoted to derive accurate correlations for the single collector efficiency, one of the key concept in the filtration theory. However, up scaling this parameter to the entire porous medium is still a challenge. The common up-scaling approach assumes the deposition to be independent of the transport history, which means that the collector efficiency is considered uniform along the porous medium. However, previous works showed that this approach is inadequate under unfavorable deposition conditions. This study demonstrates that it is not adequate even in the simplest case of favorable deposition. Computational Fluid Dynamics simulations were run for a simplify porous media geometry, composed of a vertical array of 50 identical spherical collectors. A combination of Lagrangian and Eulerian simulations were performed to analyze the particle transport under a broad range of parameters (i.e., particle size, particle density, water velocity). The results show the limits of the existing models to interpret the experimental data. In fact, the outcome evidenced that when particle deposition is not controlled by Brownian diffusion, non-exponential concentration profiles are retrieved, in contrast with the assumption of uniform efficiency. Moreover, when the deposition mechanisms of sedimentation and interception dominate, the efficiency of the first sphere of the

  16. Modacrylic anion-exchange fibers for Cr(VI) removal from chromium-plating rinse water in batch and flow-through column experiments.

    Science.gov (United States)

    Lee, Seung-Chan; Kang, Jin-Kyu; Sim, Eun-Hye; Choi, Nag-Choul; Kim, Song-Bae

    2017-11-10

    The aim of this study was to investigate Cr(VI) removal from chromium-plating rinse water using modacrylic anion-exchange fibers (KaracaronTM KC31). Batch experiments were performed with synthetic Cr(VI) solutions to characterize the KC31 fibers in Cr(VI) removal. Cr(VI) removal by the fibers was affected by solution pH; the Cr(VI) removal capacity was the highest at pH 2 and decreased gradually with a pH increase from 2 to 12. In regeneration and reuse experiments, the Cr(VI) removal capacity remained above 37.0 mg g -1 over five adsorption-desorption cycles, demonstrating that the fibers could be successfully regenerated with NaCl solution and reused. The maximum Cr(VI) removal capacity was determined to be 250.3 mg g -1 from the Langmuir model. In Fourier-transform infrared spectra, a Cr = O peak newly appeared at 897 cm -1 after Cr(VI) removal, whereas a Cr-O peak was detected at 772 cm -1 due to the association of Cr(VI) ions with ion-exchange sites. X-ray photoelectron spectroscopy analyses demonstrated that Cr(VI) was partially reduced to Cr(III) after the ion exchange on the surfaces of the fibers. Batch experiments with chromium-plating rinse water (Cr(VI) concentration = 1178.8 mg L -1 ) showed that the fibers had a Cr(VI) removal capacity of 28.1-186.4 mg g -1 under the given conditions (fiber dose = 1-10 g L -1 ). Column experiments (column length = 10 cm, inner diameter = 2.5 cm) were conducted to examine Cr(VI) removal from chromium-plating rinse water by the fibers under flow-through column conditions. The Cr(VI) removal capacities for the fibers at flow rates of 0.5 and 1.0 mL min -1 were 214.8 and 171.5 mg g -1 , respectively. This study demonstrates that KC31 fibers are effective in the removal of Cr(VI) ions from chromium-plating rinse water.

  17. Experimental investigation of a solar collector integrated with a pulsating heat pipe and a compound parabolic concentrator

    International Nuclear Information System (INIS)

    Xu, Rong Ji; Zhang, Xiao Hui; Wang, Rui Xiang; Xu, Shu Hui; Wang, Hua Sheng

    2017-01-01

    Highlights: • Solar collector integrates compound parabolic concentrator and pulsating heat pipe. • Concentrator of a concentration ratio 3.4 matches well heat flux of heat pipe. • Solar collector efficiency increases with decreasing absorber thermal resistance. • Maximum 50% efficiency of the integrated solar collector has been achieved. - Abstract: The paper reports an experimental investigation of a newly proposed solar collector that integrates a closed-end pulsating heat pipe (PHP) and a compound parabolic concentrator (CPC). The PHP is used as an absorber due to its simple structure and high heat transfer capacity. The CPC has a concentration ratio of 3.4 and can be readily manufactured by three-dimensional printing. The CPC can significantly increase the incident solar irradiation intensity to the PHP absorber and also reduce the heat loss due to the decrease in the area of the hot surface. A prototype of the solar collector has been built, consisting of a PHP absorber bent by 4 mm diameter copper tube, CPC arrayed by 10 × 2 CPC units with the collection area of 300 × 427.6 mm 2 , a hot water tank and a glass cover. HFE7100 was utilized as the working fluid at a filling ratio of 40%. The operating characteristics and thermal efficiency of the solar collector were experimentally studied. The steady and periodic temperature fluctuations of the evaporation and condensation sections of the PHP absorber indicate that the absorber works well with a thermal resistance of about 0.26 °C/W. It is also found that, as the main factor to the the thermal performance of the collector, thermal resistance of the PHP absorber decreases with increasing evaporation temperature. The collector apparently shows start-up, operational and shutdown stages at the starting and ending temperatures of 75 °C. When the direct normal irradiance is 800 W/m 2 , the instantaneous thermal efficiency of the solar collector can reach up to 50%.

  18. A numerical investigation of laminar forced convection in a solar collector with non-circular duct

    Directory of Open Access Journals (Sweden)

    Teleszewski Tomasz Janusz

    2017-01-01

    Full Text Available This paper presents a two-dimensional numerical study to investigate laminar flow in a flat plate solar collector with non-circular duct (regular polygonal, elliptical, and Cassini oval shape featuring forced convection with constant axial wall heat flux and constant peripheral wall temperature (H1 condition. Applying the velocity profile obtained for the duct laminar flow, the energy equation was solved exactly for the constant wall heat flux using the Boundary Element Method (BEM. Poiseuille and Nusselt numbers were obtained for flows having a different number of geometrical factors. The results are presented and discussed in the form of tables and graphs. The area goodness factor and volume goodness factor are calculated. The predicted correlations for Poiseuille and Nusselt numbers may be a very useful resource for the design and optimization of solar collectors with non-circular ducts.

  19. Study of a new solar adsorption refrigerator powered by a parabolic trough collector

    International Nuclear Information System (INIS)

    El Fadar, A.; Mimet, A.; Azzabakh, A.; Perez-Garcia, M.; Castaing, J.

    2009-01-01

    This paper presents the study of solar adsorption cooling machine, where the reactor is heated by a parabolic trough collector (PTC) and is coupled with a heat pipe (HP). This reactor contains a porous medium constituted of activated carbon, reacting by adsorption with ammonia. We have developed a model, based on the equilibrium equations of the refrigerant, adsorption isotherms, heat and mass transfer within the adsorbent bed and energy balance in the hybrid system components. From real climatic data, the model computes the performances of the machine. In comparison with other systems powered by flat plate or evacuated tube collectors, the predicted results, have illustrated the ability of the proposed system to achieve a high performance due to high efficiency of PTC, and high flux density of heat pipe

  20. An energy and exergy study of a solar thermal air collector

    Directory of Open Access Journals (Sweden)

    Mohseni-Languri Ehsan

    2009-01-01

    Full Text Available A solar flat plate air collector was manufactured in the north of Iran, and connected to a room as the model to study the possibility of using such solar heating systems in the northern parts of Iran. This collector was tested as a solar air heater to see how good it could be for warming up the test room during the winter. The experimental data obtained through accurate measurements were analyzed using second law approach to find the optimum mass flow rate, which leads to the maximum exergy efficiency. It was found that for the test setup at the test location, a mass flow rate of 0.0011 kg/s is the optimum mass flow rate for tested conditions which leads to the highest second law efficiency.