WorldWideScience

Sample records for plate collector subsystem

  1. Owens-Illinois subsystem design package for the SEC-601 air-cooled solar collector

    Science.gov (United States)

    1979-01-01

    The subsystem design of the SEC-601 solar collector was evaluated. The collector is of modular design and is approximately 12 feet three inches wide and eight feet seven inches tall. It contains 72 collector tube elements and weighs approximately 300 pounds. Included in this report are the subsystem performance specifications and the assembly and installation drawings of the solar collectors and manifold.

  2. Rotating field collector subsystem phase 1 study and evaluation

    Science.gov (United States)

    Jones, D.; Eibling, J. A.

    1982-10-01

    The rotating field collector system is an alternative concept in which all heliostats are mounted on a single large platform which rotates around a tower to track the azumuthal angle of the Sun. Each heliostat is mounted to the platform with appropriate pivots, linkage, and controls to provide the additional positioning required to properly direct the solar radiation onto the receiver. The results are presented of the first phase of a study to investigate the technical and economic merits of a particular type of rotating field collector subsystem. The large pie-shaped platform would revolve over an array of support pedestals by means of a roller at the top of each pedestal. Several heliostats were built to demonstrate their construction features, and the operation of both flat and amphitheater rotating fields was studied. Work included an analysis of the concepts, development of modifications and additions to make the system comply with design criteria, and cost estimates to be used for comparison with other heliostat subsystems. Because of considerably high cost estimates, the focus of a large part of the study was directed toward developing lower cost designs of major components.

  3. High performance flat plate solar collector

    Science.gov (United States)

    Lansing, F. L.; Reynolds, R.

    1976-01-01

    The potential use of porous construction is presented to achieve efficient heat removal from a power producing solid and is applied to solar air heaters. Analytical solutions are given for the temperature distribution within a gas-cooled porous flat plate having its surface exposed to the sun's energy. The extracted thermal energy is calculated for two different types of plate transparency. Results show the great improvement in performance obtained with porous flat plate collectors as compared with analogous nonporous types.

  4. Electrostatic particle collector with improved features for installing and/or removing its collector plates

    Energy Technology Data Exchange (ETDEWEB)

    Siegfried, Matthew J.; Radford, Daniel R.; Huffman, Russell K.

    2017-04-04

    An electrostatic particle collector may generally include a housing having sidewalls extending lengthwise between a first end and a second end. The housing may define a plate slot that extends heightwise within the housing between a top end and a bottom end. The housing may further include a plate access window that provides access to the bottom end of the plate slot. The collector may also include a collector plate configured to be installed within the plate slot that extends heightwise between a top edge and a bottom edge. Additionally, when the collector plate is installed within the plate slot, the bottom edge of the collector plate may be accessible from an exterior of the housing via the plate access window so as to allow the bottom edge of the collector plate to be moved relative to the housing to facilitate removal of the collector plate from the housing.

  5. 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.

  6. REVIEW OF PERFORMANCE AND ANALYSIS ISI FLAT PLATE COLLECTOR WITH MODIFIED FLAT PLATE COLLECTOR

    Directory of Open Access Journals (Sweden)

    MR.Y.Y.NANDURKAR

    2012-03-01

    Full Text Available The market of solar water heater of natural circulation type (thermo-siphon is fast growing in India. Initial cost of the solar water heater system at present is high because of store type design. It is necessary to make the product more popular by reducing the cost. This is possible by reducing area of liquid flat plate collector by increasing tube diameter and reducing riser length. Hence it is essential to make solar water heater in affordable range of the general public class. Present work is based on review of comparative performance and analysis of ISI flat plate collector with modified flat plat collector. The paper will be helpful for those who are working in the area of solar water heating system and their use in domestic areas.

  7. 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...

  8. Increasing thermal efficiency of solar flat plate collectors

    Science.gov (United States)

    Pona, J.

    A study of methods to increase the efficiency of heat transfer in flat plate solar collectors is presented. In order to increase the heat transfer from the absorber plate to the working fluid inside the tubes, turbulent flow was induced by installing baffles within the tubes. The installation of the baffles resulted in a 7 to 12% increase in collector efficiency. Experiments were run on both 1 sq ft and 2 sq ft collectors each fitted with either slotted baffles or tubular baffles. A computer program was run comparing the baffled collector to the standard collector. The results obtained from the computer show that the baffled collectors have a 2.7% increase in life cycle cost (LCC) savings and a 3.6% increase in net cash flow for use in domestic hot water systems, and even greater increases when used in solar heating systems.

  9. Solar Pilot Plant, Phase I. Preliminary design report. Volume III. Collector subsystem. CDRL item 2

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-05-01

    The Honeywell collector subsystem features a low-profile, multifaceted heliostat designed to provide high reflectivity and accurate angular and spatial positioning of the redirected solar energy under all conditions of wind load and mirror attitude within the design operational envelope. The heliostats are arranged in a circular field around a cavity receiver on a tower halfway south of the field center. A calibration array mounted on the receiver tower provides capability to measure individual heliostat beam location and energy periodically. This information and weather data from the collector field are transmitted to a computerized control subsystem that addresses the individual heliostat to correct pointing errors and determine when the mirrors need cleaning. This volume contains a detailed subsystem design description, a presentation of the design process, and the results of the SRE heliostat test program.

  10. Development of high efficiency collector plates. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Santala, T.; Sabol, R.

    1976-02-01

    Composite metal technology was used to manufacture intermetallic compound (IC) absorption surfaces and to combine them integrally with composite metal tube-in-sheet collector plates. Five material systems in which Al was one component metal and Fe, Cr, or Ni and their alloy was the other pair, were evaluated. All intermetallic compounds had high solar absorptance ..cap alpha.. approx. = 0.9. The AlNi was most promising and ..cap alpha.. > or = 0.95 and epsilon approx. = 0.3 were obtained over a broad range of compounding conditions. After eight months exposure in a flat plate collector enclosure the characteristic properties of AlNi surfaces remained virtually unchanged. Only LCS/Cu composite metal tube-in-sheet collector plates could be manufactured successfully. The technical difficulties associated with integrating the intermetallic compound and tube-in-sheet technologies make the manufacturing of composite metal collector plates at the time being economically unfeasible.

  11. 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.

  12. Detailed Modeling of Flat Plate Solar Collector with Vacuum Glazing

    Directory of Open Access Journals (Sweden)

    Viacheslav Shemelin

    2017-01-01

    Full Text Available A theoretical analysis of flat plate solar collectors with a vacuum glazing is presented. Different configurations of the collector have been investigated by a detailed theoretical model based on a combined external and internal energy balance of the absorber. Performance characteristics for vacuum flat plate collector alternatives have been derived. Subsequently, annual energy gains have been evaluated for a selected variant and compared with state-of-the-art vacuum tube collectors. The results of modeling indicate that, in the case of using advanced vacuum glazing with optimized low-emissivity coating (emissivity 0.20, solar transmittance 0.85, it is possible to achieve efficiency parameters similar to or even better than vacuum tube collectors. The design presented in this paper can be considered promising for the extension of the applicability range of FPC and could be used in applications, which require low-to-medium temperature level.

  13. Central-receiver solar-thermal power system. Collector subsystem research experiments detail design report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-02-24

    The detail design (DD) of research experiment hardware for the collector subsystem (heliostats) to support the 10 MW/sub e/ Pilot Plant preliminary design (PD) is presented. Additionally, test plans for assembly, integration, and array tests are presented, along with results of completed component/material tests. Research experiment DD and tests described were planned to provide design verification and supporting data, with hardware which either duplicates, or closely simulates the Pilot Plant PD baseline. (WHK)

  14. High temperature flat plate solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Hozumi, S.; Aso, S.; Ebisu, K.; Uchino, H.

    1981-04-01

    Improvements in the efficiency of collectors are of great importance for extending the utilization of solar energy for heating and cooling in homes. A highly efficient collector makes the system size small and decreases the system cost effectively. From the view of the amount of energy collected, the efficient collector has a multiple effect, not only because of the high increase in instantaneous efficiency, but also because of the large usable intensity range of the insolation. On the basis of a functional analysis for a flat collector, the materials and parameters were selected and optimized, and a new high temperature flat collector was designed. The collector has 2 panes. The first pane is low iron glass and the second pane is a thin film of fluorinated ethylene-propylene copolymer. The overall solar transmittance for the two panes is 0.89. The collecting panel and its water paths were formed by means of welding and hydraulic expansion. The selective absorbing surface consists of colored stainless steel whose absorption characteristic is 0.89 and emission characteristic is 0.16. The thermal insulator preventing backward heatloss consists of double layers of urethane foam and glass wool. Furthermore, the sustained method for the second pane is contrived so as to prevent water condensation on the panes and excessive elevation of the absorber temperature during no load heating.

  15. A high performance porous flat-plate solar collector

    Science.gov (United States)

    Lansing, F. L.; Clarke, V.; Reynolds, R.

    1979-01-01

    A solar collector employing a porous matrix as a solar absorber and heat exchanger is presented and its application in solar air heaters is discussed. The collector is composed of a metallic matrix with a porous surface which acts as a large set of cavity radiators; cold air flows through the matrix plate and exchanges heat with the thermally stratified layers of the matrix. A steady-state thermal analysis of the collector is used to determine collector temperature distributions for the cases of an opaque surface matrix with total absorption of solar energy at the surface, and a diathermanous matrix with successive solar energy absorption at each depth. The theoretical performance of the porous flat plate collector is shown to exceed greatly that of a solid flat plate collector using air as the working medium for any given set of operational conditions. An experimental collector constructed using commercially available, low cost steel wool as the matrix has been found to have thermal efficiencies from 73 to 86%.

  16. Standardized solar simulator tests of flat plate solar collectors. 1: Soltex collector with two transparent covers

    Science.gov (United States)

    Simon, F.

    1975-01-01

    A Soltex flat plate solar collector was tested with a solar simulator for inlet temperatures of 77 to 201 F, flux levels of 240 and 350 Btu/hr-sq ft, a collant flow rate of 10.5 lb/hr sq ft, and incident angles of 0 deg, 41.5 deg, and 65.2 deg. Collector performance is correlated in terms of inlet temperature, flux level, and incident angle.

  17. Low cost bare-plate solar air collector

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-09-01

    The purpose of this project was to develop a low cost, bare-plate collector, determine its performance for a variety of climatic conditions, analyze the economics of this type of solar collector and evaluate specific applications. 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% or greater with air preheat temperature uses up to 20/sup 0/F for one of the prototypes. The economic analyses indicated that an installed cost of between $5 and $10 per square foot would make this type of solar system economically viable. For the materials of construction and the type of fabrication and installation perceived, these costs for the bare-plate solar collector are believed to be attainable. Specific applications for preheating ventilation air for schools were evaluated and judged to be economically viable.

  18. Calculating the Solar Energy of a Flat Plate Collector

    Directory of Open Access Journals (Sweden)

    Ariane Rosario

    2014-09-01

    Full Text Available The amount of solar energy that could be obtained by a flat plate solar collector of one square meter dimension is calculated in three different locations: Tampa FL, Fairbanks AL, and Pontianak Indonesia, considering the varying sunset time for each day of the year. The results show that if the collectors are placed near the equator, more total energy could be obtained. In fact, by placing a solar collector in Pontianak, Indonesia 12.42% more solar energy can be obtained than by placing it in Tampa and 96.9% more solar energy than Alaska.

  19. Validation of CFD simulation for flat plate solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Selmi, Mohamed; Al-Khawaja, Mohammed J.; Marafia, Abdulhamid [Department of Mechanical Engineering, University of Qatar, P.O. Box 2713, Doha, State of Qatar (Qatar)

    2008-03-15

    The problem of flat plate solar energy collector with water flow is simulated and analyzed using computational fluid dynamics (CFD) software. The considered case includes the CFD modeling of solar irradiation and the modes of mixed convection and radiation heat transfer between tube surface, glass cover, side walls, and insulating base of the collector as well as the mixed convective heat transfer in the circulating water inside the tube and conduction between the base and tube material. The collector performance, after obtaining 3-D temperature distribution over the volume of the body of the collector, was studied with and without circulating water flow. An experimental model was built and experiments were performed to validate the CFD model. The outlet temperature of water is compared with experimental results and there is a good agreement. (author)

  20. 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.

  1. Certification and verification for calmac flat plate solar collector

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-27

    This document contains information used in the certification and verification of the Calmac Flat Plate Collector. Contained are such items as test procedures and results, information on materials used, Installation, Operation, and Maintenance Manuals, and other information pertaining to the verification and certification.

  2. 10-MWe solar-thermal central-receiver pilot plant: collector subsystem foundation construction. Revision No. 1

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-18

    Bid documents are provided for the construction of the collector subsystem foundation of the Barstow Solar Pilot Plant, including invitation to bid, bid form, representations and certifications, construction contract, and labor standards provisions of the Davis-Bacon Act. Instructions to bidders, general provisions and general conditions are included. Technical specifications are provided for the construction. (LEW)

  3. 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

    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...... 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.......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...

  4. Theoretical analysis of solar thermal collector and flat plate bottom reflector with a gap between them

    OpenAIRE

    Hiroshi Tanaka

    2015-01-01

    Augmentation of solar radiation absorbed on a flat plate solar thermal collector by a flat plate bottom reflector was numerically determined when there was a gap between the collector and reflector. The inclination of both the collector and reflector was assumed to be adjustable according to the season. A mirror-symmetric plane of the collector to the reflector was introduced, and a graphical model was proposed to calculate the amount of solar radiation reflected by the reflector and then abs...

  5. Progress report for the scintillator plate calorimeter subsystem

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This report covers the work completed in FY90 by ANL staff and those of Westinghouse STC and BICRON Corporation under subcontract to ANL towards the design of a compensating calorimeter based on the use of scintillator plate as the sensitive medium. It is presented as five task sections dealing with respectively mechanical design; simulation studies; optical system design; electronics development; development of rad hard plastic scintillator and wavelength shifter and a summary. The work carried out by the University of Tennessee under a subcontract from ANL is reported separately. Finally, as principal institution with responsibility for the overall management of this subsystem effort, the summary here reports the conclusions resulting from the work of the collaboration and their impact on our proposed direction of effort in FY91. This proposal, for obvious reasons is given separately.

  6. The Effect of the Configuration of the Absorber on the Performance of Flat Plate Thermal Collector

    OpenAIRE

    Yan, Moyu; Qu, Ming; Peng, Steve

    2016-01-01

    In this study, a numerical thermal analysis for a new designed flat plate thermal collector was conducted through modeling. The new flat plate thermal collector has ellipse shaped tubes inside a wavy shaped absorber, which is made of stainless steel. For the comparison, the conventional flat plate thermal collector with circular copper tubes served as a base case was also modeled. Hottel-Whillier equations were utilized to formulate thermal networks for both models developed in Engineering Eq...

  7. A dynamic simulation of a flat-plate collector system

    Science.gov (United States)

    Annino, A.

    1983-04-01

    A numerical model for the performance of a flat plate solar collector array is presented, with account taken of thermal transients and calculation on a microcomputer. The system modeled consists of a flat plate array, the heat transfer fluid, an insulated storage tank, an exchange loop for heating a secondary fluid, and a load maintained by a pump. The one-dimensional analysis includes equations for the energy balances, with consideration given to heat losses to the outside. A function is defined for the total incident solar radiation, and behavior is simulated over the entire 24-hr day, weighted by the highest and lowest recorded temperatures. Good agreement has been found with experimental data.

  8. A dynamic performance simulation model of flat-plate solar collectors for a heat pump system

    Energy Technology Data Exchange (ETDEWEB)

    Arinze, E.A.; Schoenau, G.J.; Sokhansanj, S. (Saskatchewan Univ., Saskatoon, SK (Canada). College of Engineering); Adefila, S.S.; Mumah, S.M. (Ahmadu Bello Univ., Zaria (Nigeria). Dept. of Chemical Engineering)

    1993-01-01

    Flat-plate collectors are inherently exposed to time-varying meteorological and system parameters. Thus, dynamic modeling, rather than the commonly used steady-state models, is a more accurate approach for the design and performance evaluation of flat-plate solar collectors. The dynamic model presented in this study describes the fluid, plate and cover temperatures of the collector by three different differential equations. Taylor series expansion and the Runge-Kutta method are used in the solution of the differential equations. The accuracy of the dynamic model was tested by comparing the results predicted by the model with experimental performance data obtained for a liquid-cooled flat-plate solar collector with a corrugated transparent fiberglass cover. The predicted results by the dynamic model agreed favorably with the measured experimental data for the flat-plate solar collector. Experimentally determined collector temperatures varied by a maximum of [+-]3[sup o]C from values predicted by the model. (Author)

  9. Numerical 3-D heat flux simulations on flat plate solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Villar, N. Molero; Lopez, J.M. Cejudo; Munoz, F. Dominguez; Garcia, E. Rodriguez; Andres, A. Carrillo [Grupo de Energetica, Escuela Tecnica Superior de Ingenieros Industriales, UMA, Plaza El Ejido s/n, 29013 Malaga (Spain)

    2009-07-15

    A transient 3-D mathematical model for solar flat plate collectors has been developed. The model is based on setting mass and energy balances on finite volumes. The model allows the comparison of different configurations: parallel tubes collectors (PTC), serpentine tube collectors (STC), two parallel plate collectors (TPPC), and other non-usual possibilities like the use of absorbent fluids with semitransparent or transparent plates. Transparent honeycomb insulation between plate and cover can also be modelled. The effect of temperature on the thermal properties of the materials has also been considered. The model has been validated experimentally with a commercial PTC. The model is a useful tool to improve the design of plate solar collectors and to compare different configurations. In order to show the capabilities of the model, the performance of a PTC collector with non-uniformity flow is analysed and compared with experimental data from literature with good agreement. (author)

  10. 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.

  11. Natural convection characteristics of flat plate collectors. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Randall, K.R.; Wl-Wakil, M.M.; Mitchell, J.W.

    1977-09-01

    The results of an experimental investigation into the convective heat losses in large aspect ratio flat-plate solar collectors are described. An experimental study has been undertaken on a specially designed test cell using a 3 inch Mach-Zehnder interferometer. Air at atmospheric pressure was used as the heat-transfer fluid. The experimental results include interferograms which show the thermal boundary layer formations and the temperature profiles. Local temperature profiles have been analyzed through the use of an optical comparator to determine local Nusselt number profiles, which have, in turn, been integrated to give average heat-transfer results. Angles of inclination from the horizontal of 45, 60, 75 and 90 degrees have been investigated. Aspect ratios from 9 to 36 were examined over a Rayleigh number range of 4,000 to 310,000. Finally, heat-transfer correlations have been developed for the prediction of local Nusselt numbers in the starting and departure corners and for the average heat-transfer results as a function of collector tilt angle.

  12. Central Receiver Solar Thermal Power System, Phase 1. CDRL Item 2. Pilot Plant preliminary design report. Volume III, Book 1. Collector subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The central receiver system consists of a field of heliostats, a central receiver, a thermal storage unit, an electrical power generation system, and balance of plant. This volume discusses the collector field geometry, requirements and configuration. The development of the collector system and subsystems are discussed and the selection rationale outlined. System safety and availability are covered. Finally, the plans for collector portion of the central receiver system are reviewed.

  13. Theoretical analysis of solar thermal collector and flat plate bottom reflector with a gap between them

    Directory of Open Access Journals (Sweden)

    Hiroshi Tanaka

    2015-11-01

    Full Text Available Augmentation of solar radiation absorbed on a flat plate solar thermal collector by a flat plate bottom reflector was numerically determined when there was a gap between the collector and reflector. The inclination of both the collector and reflector was assumed to be adjustable according to the season. A mirror-symmetric plane of the collector to the reflector was introduced, and a graphical model was proposed to calculate the amount of solar radiation reflected by the reflector and then absorbed on the collector. The performance was analyzed for three typical days at a latitude of 30°N. Solar radiation absorbed on the collector can be increased by the bottom reflector even if there is a gap between the collector and reflector. The optimum inclinations of both the collector and reflector are almost the same while the gap length is less than the lengths of the collector and reflector. However, the range of inclination of the reflector that can increase the solar radiation absorbed on the collector decreases with an increase in gap length, and the solar radiation absorbed on the collector rapidly decreased with an increase in the gap length when the reflector and/or collector were not set at a proper angle.

  14. 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.

  15. Improvement of flat plate collectors for solar energy conversion

    Science.gov (United States)

    Boeck, H.; Hallermayer, R.; Schoelkopf, W.; Sizman, R.

    1984-03-01

    Selective absorption for thermal conversion of radiative energy was investigated. Improvement and operation of various measuring devices for absorption and emission are presented. Selective coatings were produced by vapor deposition and galvanic treatment. Calculations of the transmittance of turbular collector fields are presented. Operational Characteristics of Collector were examined. A collector test field with simultaneous recording of data from 24 collectors or uncovered absorbers was built and connected to a high performance microprocessor system. The transient behavior of collectors by variation of the irradiation and the collector inlet temperature were investigated. A mechanism for stratification of hot water of fluctuating inlet temperature in a storage tank was studied. The operating conditions of a heat pump installed in the collector test plant are investigated. A large domestic hot water system is equipped with temperature sensors and flowmeters for computer recording.

  16. 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.

  17. Experimental and numerical investigation of a flat-plate solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, A. [Departamento de Construcciones Navales, E.U. Politecnica, Universidade da Coruna, 15405 Ferrol (Spain); Cabeza, O. [Departamento de Fisica, Universidade da Coruna, 15072 A Coruna (Spain); Muniz, M.C. [Departamento de Matematica Aplicada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Varela, L.M. [Departamento de Fisica de la Materia Condensada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain)

    2010-09-15

    In the present paper we present an experimental analysis and a thermal and hydrodynamic modelling of a newly designed flat-plate solar collector characterized by its corrugated channel and by the high surface area directly in contact with the heat transport fluid. The thermal and hydrodynamic modelling of the collector has been performed by means of the Finite Element Method (FEM), validated with analytical results for a well-known fin-and-tube type solar collector. The thermodynamic efficiency of the collector is analyzed by means of its experimental heating curves. The yield of the new collector has been compared to a previously existing commercial collector of related geometry but with less area in direct contact with the heat transport fluid. The experimental results are seen to adequately fit the simulation predictions, and a methodology to use in order to compute the parameters characterizing the thermal behavior of the collector is introduced. (author)

  18. 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.

  19. Solar Pilot Plant Phase I, detailed design report: collector subsystem research experiment. CDRL Item No. 6 (Approved)

    Energy Technology Data Exchange (ETDEWEB)

    1976-08-31

    The configurations of the experimental heliostat, power and control system, and support elements for the Barstow Solar Pilot Plant are described, and the analytical and experimental determination of performance parameters is discussed. A system analysis is presented, including demonstration of pointing accuracy by error analysis, and demonstration of loop performance by simulation. Engineering model test plans are given that are to evaluate subassemblies, processes, and procedures as well as provide insight into best tests for heliostat subsystem testing. Mirror module test data are analyzed. A comprehensive test plan for the experimental model is presented. Appended are: a heliostat power consumption analysis; collector subsystem research experiment detail specification; structural analysis; solar image analysis; computer and software information; breadboard test data; simulation of the heliostat control loop; mirror module reflectance measurements; plywood frame fixed focus mirror module test data; techniques for redirected image characterization; performance of a meteorological measuring system; and heliostat design data. (LEW)

  20. A Dynamic Multinode Model for Component-Oriented Thermal Analysis of Flat-Plate Solar Collectors

    OpenAIRE

    Reiter, Christoph N.; Christoph Trinkl; Wilfried Zörner; Hanby, Vic I.

    2015-01-01

    A mathematical model of a flat-plate solar collector was developed on the basis of the physical principles of optics and heat transfer in order to determine collector’s component temperatures as well as collector efficiency. In contrast to many available models, the targeted use of this dynamic model is the detailed, theoretical investigation of the thermal behaviour of newly developed or adjusted collector designs on component level, for example, absorber, casing, or transparent cover. The d...

  1. A Didactic Experiment and Model of a Flat-Plate Solar Collector

    Science.gov (United States)

    Gallitto, Aurelio Agliolo; Fiordilino, Emilio

    2011-01-01

    We report on an experiment performed with a home-made flat-plate solar collector, carried out together with high-school students. To explain the experimental results, we propose a model that describes the heating process of the solar collector. The model accounts quantitatively for the experimental data. We suggest that solar-energy topics should…

  2. Performance Study of a Double-Pass Thermoelectric Solar Air Collector with Flat-Plate Reflectors

    Science.gov (United States)

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

    2012-06-01

    In this paper the results of the influence of flat-plate reflectors made of aluminum foil on the performance of a double-pass thermoelectric (TE) solar air collector are presented. The proposed TE solar collector with reflectors was composed of transparent glass, an air gap, an absorber plate, TE modules, a rectangular fin heat sink, and two flat-plate reflectors. The flat-plate reflectors were placed on two sides of the TE solar collector (east and west directions). The TE solar collector was installed on a one-axis sun-tracking system to obtain high solar radiation. Direct and reflected incident solar radiation heats up the absorber plate so that a temperature difference is created across the TE modules to generate a direct current. Only a small part of the absorbed solar radiation is converted to electricity, while the rest increases the temperature of the absorber plate. Ambient air flows through the heat sink located in the lower channel to gain heat. The heated air then flows to the upper channel, where it receives additional heating from the absorber plate. Improvements to the thermal energy and electrical power outputs of the system can be achieved by the use of the double-pass collector system with reflectors and TE technology. It was found that the optimum position of the reflectors is 60°, which gave significantly higher thermal energy and electrical power outputs compared with the TE solar collector without reflectors.

  3. Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

    Science.gov (United States)

    Vairamani, K.; Venkatesh, K. Arun; Mathivanan, N.

    2011-01-01

    Computing the efficiency of flat-plate collector is vital in solar thermal system testing. This paper presents the design of ZigBee enabled data acquisition system for instantaneous flat-plate collector efficiency calculation. It involves measurement of parameters like inlet and outlet fluid temperatures, ambient temperature and solar radiation intensity. The designed system has a base station and a sensor node. ZigBee wireless communication protocol is used for communication between the base station and the sensor node for wireless data acquisition. The wireless sensor node which is mounted over the collector plate includes the necessary sensors and associated signal-conditioners. An application program has been developed on LabVIEW platform for data acquisition, processing and analysis and is executed in base station PC. Instantaneous flat-plate collector efficiency is computed and reported.

  4. A graphical approach to the efficiency of flat-plate collectors

    Science.gov (United States)

    Selcuk, M. K.

    1978-01-01

    A nomogram is described which can be used to determine the thermal performance of flat plate solar collectors, resulting in two performance factors: the net absorptance and the net heat loss coefficient. The nomogram takes into account angle of incidence, collector slope, absorber plate design, insulating materials, thicknesses, optical properties of absorbing surfaces and glazing materials, and flow factors. A case example is given to illustrate the use of the nomogram.

  5. A diagram for defined flat plate solar collector area for solar floor heating

    Energy Technology Data Exchange (ETDEWEB)

    Altuntop, N.; Tekin, Y. [Erciyes University, Dept. of Mechanical Engineering (Turkey); Cengel, Y.A. [Nevada Reno University, Dept. of Mechanical Engineering, NV (United States)

    2000-07-01

    In winters, one of the best ways to heat living areas by using the low- temperature - water obtained from flat-plate solar collectors is the floor heating. In floor heating, low temperature-water (30 + 60 deg C) can be used and heat can be stored in water when solar radiation is not possible. In this study, it is aimed to define collector surface needed to supply heat for floor heating. It is also aimed to define and explain the diagram developed for every heating months. The calculations about the sun geometry are used to define the amount of radiation coming in to the collectors. Formulations are made about the definition of solar radiation absorbed by the collectors, the total heat loss coefficient, and the collector plate surface temperature. These formulations are transformed in to the diagram. In addition, the studies, heat transfer calculations and design parameters about the floor of the heating areas are used. A combined collector floor heating diagram is obtained. This diagram is used to define collector surface area necessary to supply heat for floor heated places. In this diagram, the collector surface area is obtained by giving the heat capacity of the place area, floor surface temperature, approximate modulation distance of the floor, the elevation of city, collector slope angle, wind speed, sun shine lime and the amount of the solar radiation obtained from the solar radiation diagram. (authors)

  6. Influences of the Twisted Strips Insertion on the Performance of Flat Plate Water Solar Collector

    Directory of Open Access Journals (Sweden)

    Jafar M. Hassan

    2015-09-01

    Full Text Available In order to enhance the efficiency of flat plate solar water collectors without changing in its original shape and with low additional cost, twisted strips are inserted inside its riser pipes. Three flat plate collectors are used for test. Family of twisted strips are inserted inside each collector risers with different twisted ratios (TR=3,4,5. The collectors are connected in parallel mode (Z-Configuration and are exposed to the same conditions (solar radiation and ambient temperature .The experimental results show that, the highest heat transfer rate occurs at twisted ratio (3 .Consequently, for the same twisted ratio the daily efficiencies for the solar collector at different flow rate used (60,100 and 150 ℓ /hr. were 49 %, 57% and 63% respectively.

  7. A Numerical Study on the Performance of an Open-type Flat-plate Solar Collector

    OpenAIRE

    Song, Baoyin; Inaba, Hideo; Horibe, Akihiko

    1999-01-01

    A set mathematical models was developed for predicting the performance of an open-type flat-plate solar collector, and solved numerically through an implicit difference method. The effects of various parameters on the absorption of solar energy for the collector were investigated. The results showed that the solar energy absorptance of the open-type flat-plate collector was relatively high especially for the region where the weather was humid and hot, and there were an optimum length and an o...

  8. Central receiver solar thermal power system, Phase 1. CRDL Item 2. Pilot plant preliminary design report. Volume III, Book 2. Collector subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The methods and plans for the manufacture of the 10-MW collector heliostats and associated controls for the pilot plant are detailed. An in-depth description of the production, installation, and verification testing of heliostats for the pilot plant is presented. Specifications for the performance, design, and test requirements for the pilot plant collector subsystem are included. Also, a heliostat location summary report is given. (WHK)

  9. A diagram for defined solar radiation absorbed per unit area of flat plate solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Tekin, Y.; Altuntop, N. [Erciyes University, Dept. of Mechanical Engineering (Turkey); Cengel, Y.A. [Nevada Reno University, Dept. of Mechanical Engineering, NV (United States); Cengel, Y.A. [Nevada University, Dept. Mechanical Engineering, Reno, NV (United States)

    2000-07-01

    In Erciyes University, the Solar House (28.75 m{sup 2}) is heated from the floor by using flat plate liquid solar collectors. Required solar radiation for heating and heat losses are calculated. In this work, the required calculations for Erciyes Solar House were generalized and required calculation were done to evaluate absorbed solar radiation per unit surface of the flat plate liquid collector. At the end, three generalized diagrams for nine different months are obtained using obtained numerical values. The goal of preparing diagrams is to determine absorbed solar radiation per unit surface area of flat plate liquid collector at any instant at any latitude, In this work, the diagram is explained by means of sample calculations for November. This diagram was prepared to find out absorbed solar radiation per unit area of black surface collector by means obtained equations. With this diagram, all instant solar radiation can be evaluated in 19 steps. (authors)

  10. REVIEW ON POROUS AND NON-POROUS FLAT PLATE AIR COLLECTOR WITH MIRROR ENCLOSURE

    Directory of Open Access Journals (Sweden)

    M. PRADHAPRAJ,

    2010-09-01

    Full Text Available In solar air heater, flat plat collectors are the best heat transferring devices. But the effectiveness of these collectorsis very low because of lack of technology. Solar assisted heated air is successfully used for drying applications and space heating under controlled conditions. From the solar flat plate air heater the hot air is transferred to a conventional dryer or to the combined heater and drying chamber directly. Hence, solar assisted air heaters arecheaper and reliable. The important factors affecting these systems are the solar radiation, mechanical loading, temperature and leakage. The air heater efficiency depends on the design of the system as well as the construction materials and the assembly. The solar air heating systems has acceptable life span of 15 to 20 years. The addition ofside mirror enclosures is to increase the amount of solar radiation absorption at the collector plate so that the collector increases the yield and operate in a higher temperature range. Therefore with the addition of side mirrors one can able to maximize the output of fixed flat plate collectors. A flat plate air collector will be more efficient if it is made up of porous medium when comparing it with the non porous collectors according to the study. In this paper, the performances of porous and non-porous absorber plates are discussed. Also the possible methods of finding out air leakages and the methodology adopted for the performance and efficiency calculations are also discussed.

  11. 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.

  12. Development and fabrication of a concentrating solar collector subsystem (quarterly reports)

    Energy Technology Data Exchange (ETDEWEB)

    1978-07-01

    Work done from January 1, 1978 through June 30, 1978, including several types of testing and results and evaluation of the structural design of the Northrup ''ML Series'' Concentrating Solar Collector, Model NSC-01-0732 and the Attitude Control System is reported. Efficiency tests, stagnation--defocusing tests, internal vacuum tests, pressure tests, tracking tests, fluttering tests, accelerated swivel and flexible joint life tests, and certification are described.

  13. Comparison under a simulated sun of two black-nickel-coated flat-plate solar collectors with a nonselective black-paint-coated collector

    Science.gov (United States)

    Simon, F. F.

    1975-01-01

    A performance evaluation was made of two, black nickel coated, flat plate solar collectors. Collector performance was determined under a simulated sun for a wide range of inlet temperatures, including the temperature required for solar powered absorption air conditioning. For a basis of comparison a performance test was made on a traditional, two glass, nonselective, black paint coated, flat plate collector. Performance curves and performance parameters are presented to point out the importance of the design variables which determine an efficient collector. A black nickel coated collector was found to be a good performer at the conditions expected for solar powered absorption air conditioning. This collector attained a thermal efficiency of 50 percent at an inlet temperature of 366 K (200 F) and an incident flux of 946 watts/sq m (300 Btu/hr-sq ft).

  14. Design, construction and testing of a liquid-heating flat-plate solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, R E

    1980-02-01

    The purpose of this study was to design, construct, and test a liquid-heating flat-plate solar collector. From the literature search, information was gathered concerning the basic components of the collector, the different processes and materials that can be used in the construction of these components, and their advantages and disadvantages. The literature search also revealed a method used to measure the performance of the collector in terms of efficiency and heat output. Design considerations were then listed for each of the major components as well as the collector as a single unit. Then, each component was designed, taking into consideration the final assembly of the completed unit. Detailed designs were required for the absorber plate and the box and frame assembly because of their complexity in construction and assembly. Once the components were designed, the construction details were arranged in a logical sequence, again considering the final assembly of the unit. The collector was then carefully constructed and assembled following the design details. After the solar collector was assembled completely, tests were made, data were obtained and recorded, and a collector performance curve was developed.

  15. Flat-plate solar-collector performance data base and user's manual

    Science.gov (United States)

    Kirkpatrick, D. L.; Kolar, W. A.

    1983-07-01

    The reader is provided with a thorough understanding on the type of collector thermal performance information which is required in active system design and analysis. Thermal performance test data on 109 commercially available solar collectors which were evaluated in a single, uniform test program, the Interim Solar Collector Test (ISCT) Program are given. In addition to recounting the ISCT program and its results, the an introduction is given on the engineering and physics of a flat-plate solar collector operation. A step-by-step analysis of heat gains and losses is provided to help the reader understand both the source and applicability of the parameters used to describe collector thermal performance. A brief description of the engineering basis for the ASHRAE Standard 93-77 test procedure and the method are included. To demonstrate the sensitivity to variations of collector performance parameters of the annual output of representative solar heating systems, three sets of F-Chart (4.0) system performance predictions are given. Finally, a sensitivity analysis study is presented which considers the heat loss and optical gain parameters of flat-plate collectors, in terms of how they affect the overall solar heating system solar fraction.

  16. 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.

  17. Studies on solar flat plate collector evaporation systems for tannery effluent (soak liquor)

    Institute of Scientific and Technical Information of China (English)

    SRITHAR K.; MANIA.

    2006-01-01

    Heat and mass transfer analysis of an incompressible, laminar boundary layer over solar flat plate collector evaporation systems for tannery effluent (soak liquor) is investigated. The goveming equations are solved for various liquid to air velocity ratios. Profiles of velocity, temperature and concentration as well as their gradients are presented. The heat transfer and mass transfer coefficients thus obtained are used to evaluate mass of water evaporated for an inclined fibre-reinforced plastic (FRP)solar flat plate collector (FPC) with and without cover. Comparison of these results with the experimental performance shows encouraging trend of good agreement between them.

  18. Experimental study on flat plate air solar collector using a thin sand layer

    Science.gov (United States)

    Lati, Moukhtar; Boughali, Slimane; Bouguettaia, Hamza; Mennouche, Djamel; Bechki, Djamel

    2016-07-01

    A flat plate air solar collector was constructed in the laboratory of New and Renewable Energy in Arid Zones LENREZA, Ouargla University-South East Algeria. The absorber of the flat plate air solar collector was laminated with a thin layer of local sand. This acted as a thermal storage system (packed bed) with a collecting area of 2.15 m2 (0.86 m × 2.5 m). It was noticed that the solar heater integrated with the thermal storage material delivered comparatively higher temperatures; thus, giving a better efficiency than the air heater without the thermal storage system.

  19. Potential of size reduction of flat-plate solar collectors when applying MWCNT nanofluid

    Science.gov (United States)

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

    2013-06-01

    Flat-plate solar collector is the most popular type of collector for hot water system to replace gas or electric heater. Solar thermal energy source is clean and infinite to replace fossil fuel source that is declining and harmful to the environment. However, current solar technology is still expensive, low in efficiency and takes up a lot of space. One effective way to increase the efficiency is by applying high conductivity fluid as nanofluid. This paper analyzes the potential of size reduction of solar collector when MWCNT nanofluid is used as absorbing medium. The analysis is based on different mass flow rate, nanoparticles mass fraction, and presence of surfactant in the fluid. For the same output temperature, it can be observed that the collector's size can be reduced up to 37% of its original size when applying MWCNT nanofluid as the working fluid and thus can reduce the overall cost of the system.

  20. Heat transfer and energy analysis of a solar air collector with smooth plate

    Science.gov (United States)

    Chabane, Foued; Moummi, Noureddine

    2014-04-01

    The heat transfer and thermal performance of a single pass solar air heater a smooth plate was investigated experimentally. In the present paper, energy and heat transfer analysis of a solar air collector with smooth plate, this technique is used to determine the optimal thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different mass flow rate varying in the array 0.0108-0.0202 kg/s with five values, solar intensity; tilt angle and ambient temperature. We discuss the thermal behavior of this type of collector with new design and with my proper construction. An experimental study was carried out on a prototype installed on the experimental tests platform within the University of Biskra in the Algeria. The effects of air mass flow rate, emissivity of channel plates and wind heat transfer coefficient on the accuracy of the criterion are also investigated.

  1. Flat plate solar collector design and performance. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The bibliography contains citations concerning the design and thermal efficiency of air and liquid type flat plate solar collectors. Topics include convection characteristics, methods to reduce heat loss, optical coatings, and corrosion prevention. Emphasis is on research and modeling. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  2. Flat plate solar collector design and performance. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The bibliography contains citations concerning the design and thermal efficiency of air and liquid type flat plate solar collectors. Topics include convection characteristics, methods to reduce heat loss, optical coatings, and corrosion prevention. Emphasis is on research and modeling. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  3. Flat plate solar collector design and performance. Citations from the NTIS data base

    Science.gov (United States)

    Hundemann, A. S.

    1980-09-01

    Federally funded research on the design and thermal efficiency of air and liquid type flat plate collectors is discussed. Topic areas cover convection characteristics, methods to reduce heat loss, optical coatings, and corrosion control. Emphasis of the bibliography is on basic research studies. This updated bibliography contains 196 citations, 36 of which are new entries to the previous edition.

  4. Hot-air flat-plate solar collector-design package

    Science.gov (United States)

    1979-01-01

    Report contains design data, performance specifications, and drawings for hot-air flat-plate solar-energy collector. Evaluation consists of tests on thermal performance time constance, and incidence angle modifier test. Results are presented in table and graph form and are analyzed in detail.

  5. Hot-air flat-plate solar collector-design package

    Science.gov (United States)

    1979-01-01

    Report contains design data, performance specifications, and drawings for hot-air flat-plate solar-energy collector. Evaluation consists of tests on thermal performance time constance, and incidence angle modifier test. Results are presented in table and graph form and are analyzed in detail.

  6. Heat transfer in a low latitude flat-plate solar collector

    Directory of Open Access Journals (Sweden)

    Oko C.O.C.

    2012-01-01

    Full Text Available Study of rate of heat transfer in a flat-plate solar collector is the main subject of this paper. Measurements of collector and working fluid temperatures were carried out for one year covering the harmattan and rainy seasons in Port Harcourt, Nigeria, which is situated at the latitude of 4.858oN and longitude of 8.372oE. Energy balance equations for heat exchanger were employed to develop a mathematical model which relates the working fluid temperature with the vital collector geometric and physical design parameters. The exit fluid temperature was used to compute the rate of heat transfer to the working fluid and the efficiency of the transfer. The optimum fluid temperatures obtained for the harmattan, rainy and yearly (or combined seasons were: 317.4, 314.9 and 316.2 [K], respectively. The corresponding insolation utilized were: 83.23, 76.61 and 79.92 [W/m2], respectively, with the corresponding mean collector efficiency of 0.190, 0.205 and 0.197 [-], respectively. The working fluid flowrate, the collector length and the range of time that gave rise to maximum results were: 0.0093 [kg/s], 2.0 [m] and 12PM - 13.00PM, respectively. There was good agreement between the computed and the measured working fluid temperatures. The results obtained are useful for the optimal design of the solar collector and its operations.

  7. Evaluation of All-Day-Efficiency for selected flat plate and evacuated tube collectors

    Science.gov (United States)

    1981-01-01

    An evaluation of all day efficiency for selected flat plate and evacuated tube collectors is presented. Computations are based on a modified version of the NBSIR 78-1305A procedure for all day efficiency. The ASHMET and NOAA data bases for solar insolation are discussed. Details of the algorithm used to convert total (global) horizontal radiation to the collector tilt plane of the selected sites are given along with tables and graphs which show the results of the tests performed during this evaluation.

  8. Operational demonstration of a field of high performance flat plate collectors with isothermal heat transport

    Science.gov (United States)

    Merges, V.; Klippel, E.

    1983-12-01

    A solar plant with 21 sq m of highly efficient flat plate collectors and which requires no electricity is described. Heat transport is provided by saturated steam that condenses in a four cubic meter storage tank. The operation temperature is set by the buffer gas pressure between 100 and 140 C, and an absorption chiller is simulated as a heat consumer. The solar collectors were observed to exhibit high performance. Heat transport and temperature control offered high reliability and the thermal stratification in the tank was satisfactory. The positive result permits the design and construction of larger solar plants following the same technical principles.

  9. Fixed flat plate collector with a reversible vee-trough concentrator

    Science.gov (United States)

    Selcuk, M. K.

    1976-01-01

    An asymmetrical-reversible vee-trough concentrator for use both with nonevacuated and evacuated receivers is proposed in order to improve the performance of a fixed flat plate collector. The device is capable of maintaining a year-round concentration factor of about 2 while eliminating the complications of the tilt adjustments of the collector box assembly. Efficiency improvements and cost reductions for temperatures of about 100 and 200 C are offered for the nonvacuum and vacuum tube versions, respectively. A major advantage of the vee-trough is the enhancement of the incident flux, thus extending the collection period. The vacuum collector is suitable for supplying heat to solar Rankine systems, while the nonvacuum version can be used for air conditioning purposes via an absorption air conditioner.

  10. Analysis of PV/T flat plate water collectors connected in series

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Swapnil; Tiwari, G.N. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)

    2009-09-15

    Photovoltaic-thermal (PV/T) technology refers to the integration of a PV and a conventional solar thermal collector in a single piece of equipment. In this paper we evaluate the performance of partially covered flat plate water collectors connected in series using theoretical modeling. PV is used to run the DC motor, which circulates the water in a forced mode. Analytical expressions for N collectors connected in series are derived by using basic energy balance equations and computer based thermal models. This paper shows the detailed analysis of thermal energy, exergy and electrical energy yield by varying the number of collectors by considering four weather conditions (a, b, c and d type) for five different cities (New Delhi, Bangalore, Mumbai, Srinagar, and Jodhpur) of India. Annual thermal and electrical energy yield is also evaluated for four different series and parallel combination of collectors for comparison purpose considering New Delhi conditions. This paper also gives the total carbon credit earned by the hybrid PV/T water heater investigated as per norms of Kyoto Protocol for New Delhi climatic conditions. Cost analysis has also been carried out. It is observed that the collectors partially covered by PV module combines the production of hot water and electricity generation and it is beneficial for the users whose primary requirement is hot water production and collectors fully covered by PV is beneficial for the users whose primary requirement is electricity generation. We have also found that if this type of system is installed only in 10% of the total residential houses in Delhi then the total carbon credit earned by PV/T water heaters in terms of thermal energy is USD $144.5 millions per annum and in terms of exergy is USD $14.3 millions per annum, respectively. (author)

  11. A Dynamic Multinode Model for Component-Oriented Thermal Analysis of Flat-Plate Solar Collectors

    Directory of Open Access Journals (Sweden)

    Christoph N. Reiter

    2015-01-01

    Full Text Available A mathematical model of a flat-plate solar collector was developed on the basis of the physical principles of optics and heat transfer in order to determine collector’s component temperatures as well as collector efficiency. In contrast to many available models, the targeted use of this dynamic model is the detailed, theoretical investigation of the thermal behaviour of newly developed or adjusted collector designs on component level, for example, absorber, casing, or transparent cover. The defined model is based on a multinode network (absorber, fluid, glazing, and backside insulation containing the relevant physical equations to transfer the energy. The heat transfer network covers heat conduction, convection, and radiation. Furthermore, the collector optics is defined for the plane glazing and the absorber surface and also considers interactions between them. The model enables the variation of physical properties considering the geometric parameters and materials. Finally, the model was validated using measurement data and existing efficiency curve models. Both comparisons proved high accuracy of the developed model with deviation of up to 3% in collector efficiency and 1 K in component temperatures.

  12. KARAKTERISTIK PENGERINGAN CHIPS MANGGA MENGGUNAKAN KOLEKTOR SURYA KACA GANDA [Characteristics of Mango Chips Drying Using a Double Plated Solar Collector

    Directory of Open Access Journals (Sweden)

    Safrani

    2012-12-01

    Full Text Available The objectives of this research were to study the characteristics of mango chips drying using a double plated solar collector. The materials used were sliced mangoes with the thickness of 3, 6, and 8 mm. The equipments used for this research were double plated solar collector, thermocouple, digital balance, thermometer, vacuum oven, and desiccators. The research parameters included the rate of heat energy absorbed by the double plated solar collector, the heat energy losses, the efficiency of the double plated solar collector and the moisture content of the chips. The results of this study suggested that the use of double plated solar collector could increase the temperature and the amount of heat energy, thus speed up the drying process of the mango chips. The energy needed to evaporate the moisture content in mango decreased in proportion to the increase in drying time. The difference in mango chips’ thickness resulted in different decrease rate in water content until it reached a constant state. The efficiency of the double plated solar collector was 77.82%.

  13. Design optimization of sinusoidal glass honeycomb for flat plate solar collectors

    Science.gov (United States)

    Mcmurrin, J. C.; Buchberg, H.

    1980-01-01

    The design of honeycomb made of sinusoidally corrugated glass strips was optimized for use in water-cooled, single-glazed flat plate solar collectors with non-selective black absorbers. Cell diameter (d), cell height (L), and pitch/diameter ratio (P/d) maximizing solar collector performance and cost effectiveness for given cell wall thickness (t sub w) and optical properties of glass were determined from radiative and convective honeycomb characteristics and collector performance all calculated with experimentally validated algorithms. Relative lifetime values were estimated from present materials costs and postulated production methods for corrugated glass honeycomb cover assemblies. A honeycomb with P/d = 1.05, d = 17.4 mm, L = 146 mm and t sub w = 0.15 mm would provide near-optimal performance over the range delta T sub C greater than or equal to 0 C and less than or equal to 80 C and be superior in performance and cost effectiveness to a non-honeycomb collector with a 0.92/0.12 selective black absorber.

  14. Influence of wire-coil inserts on the thermo-hydraulic performance of a flat-plate solar collector

    Science.gov (United States)

    Herrero Martín, R.; García, A.; Pérez-García, J.

    2012-11-01

    Enhancement techniques can be applied to flat-plate liquid solar collectors towards more compact and efficient designs. For the typical operating mass flow rates in flat-plate solar collectors, the most suitable technique is inserted devices. Based on previous studies from the authors, wire coils were selected for enhancing heat transfer. This type of inserted device provides better results in laminar, transitional and low turbulence fluid flow regimes. To test the enhanced solar collector and compare with a standard one, an experimental side-by-side solar collector test bed was designed and constructed. The testing set up was fully designed following the requirements of EN12975-2 and allow us to accomplish performance tests under the same operating conditions (mass flow rate, inlet fluid temperature and weather conditions). This work presents the thermal efficiency curves of a commercial and an enhanced solar collector, for the standardized mass flow rate per unit of absorber area of 0.02 kg/sm2 (in useful engineering units 144 kg/h for water as working fluid and 2 m2 flat-plate solar collector of absorber area). The enhanced collector was modified inserting spiral wire coils of dimensionless pitch p/D = 1 and wire-diameter e/D = 0.0717. The friction factor per tube has been computed from the overall pressure drop tests across the solar collectors. The thermal efficiency curves of both solar collectors, a standard and an enhanced collector, are presented. The enhanced solar collector increases the thermal efficiency by 15%. To account for the overall enhancement a modified performance evaluation criterion (R3m) is proposed. The maximum value encountered reaches 1.105 which represents an increase in useful power of 10.5% for the same pumping power consumption.

  15. 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.

  16. 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.

  17. Multi-objective genetic algorithm for the optimization of a flat-plate solar thermal collector.

    Science.gov (United States)

    Mayer, Alexandre; Gaouyat, Lucie; Nicolay, Delphine; Carletti, Timoteo; Deparis, Olivier

    2014-10-20

    We present a multi-objective genetic algorithm we developed for the optimization of a flat-plate solar thermal collector. This collector consists of a waffle-shaped Al substrate with NiCrOx cermet and SnO(2) anti-reflection conformal coatings. Optimal geometrical parameters are determined in order to (i) maximize the solar absorptance α and (ii) minimize the thermal emittance ε. The multi-objective genetic algorithm eventually provides a whole set of Pareto-optimal solutions for the optimization of α and ε, which turn out to be competitive with record values found in the literature. In particular, a solution that enables α = 97.8% and ε = 4.8% was found.

  18. Conclusions and recommendations for the testing of flat-plate solar collector thermal performance and durability

    Science.gov (United States)

    Waksman, D.; Thomas, W. C.

    1984-12-01

    The results of studies, by the National Bureau of Standards, of the reliability and durability of eight different types of flat plate solar collectors representative of equipment available in 1977 are reported. The installations were made in four sites believed to typify various U.S. climates. The stability of the thermal performance and material properties was tracked, and measured again after moving the units inside for exposure to artificial sunlight. The stagnation measurement techniques employed to evaluate the collectors were judged adequate, provided the tests are made on-site and out of doors. It is noted that the instrumentation used to gather sufficient data for valid analyses may experience performance decrements due to the necessarily long monitoring intervals, i.e., several years.

  19. Theoretical investigation on thermal performance of heat pipe flat plate solar collector with cross flow heat exchanger

    Science.gov (United States)

    Xiao, Lan; Wu, Shuang-Ying; Zhang, Qiao-Ling; Li, You-Rong

    2012-07-01

    Based on the heat transfer characteristics of absorber plate and the heat transfer effectiveness-number of heat transfer unit method of heat exchanger, a new theoretical method of analyzing the thermal performance of heat pipe flat plate solar collector with cross flow heat exchanger has been put forward and validated by comparisons with the experimental and numerical results in pre-existing literature. The proposed theoretical method can be used to analyze and discuss the influence of relevant parameters on the thermal performance of heat pipe flat plate solar collector.

  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

    On an average about 40% of world energy is used in residential buildings and the largest energy consumption is allocated to the cooling and air-conditioning systems. So every attempt to economize energy consumption is very valuable. In this research a nocturnal radiative cooling system with flat...... 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. Flat plate collector with external reflectors (RefleC). Experiences withthe development; Flachkollektor mit externen Reflektoren (RefleC). Entwicklungserfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Hess, S.; Oliva, A.; Di Lauro, P.; Klemke, M.; Hermann, M.; Stryi-Hipp, G. [Fraunhofer-Institut fuer Solare Energiesysteme ISE, Freiburg (Germany); Kallwellis, V.; Kramp, G.; Eisenmann, W. [Wagner und Co. Solartechnik GmbH, Coelbe (Germany); Hanby, V. [DMU Leicester (United Kingdom). Inst. of Energy and Sustainable Development

    2010-07-01

    In cooperation with the Fraunhofer Institute for Solar Energy Systems (Freiburg, Federal Republic of Germany), the company Wagner and Co. Solar Technology (Coelbe, Federal Republic of Germany) developed a stationary concentrated, double-covered flat plate collector with an external reflector for generating process heat up to a temperature of 150 C. This prototype has a half-CPC reflector which is approximated by three flat segments. The reflectors use the distance between the collectors and serves simultaneously as a supporting structure. The collector is designed so that the aperture is not shaded. The authors of the contribution under consideration present the WKI curves and the IAM curves as a test pattern as well as a simulation of the annual energy yield. According to the simulation, the Reflec-collector has an annual energy yield which is greater by 64 % than that of the double-covered base-collector.

  2. 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....

  3. Heat Transfer Analysis of a Flat-plate Solar Collector Running a Solid Adsorption Refrigerator

    Directory of Open Access Journals (Sweden)

    S. Thiao

    2014-05-01

    Full Text Available Adsorption solar cooling appears to have prospect in the tropical countries. The present study is a theoretical investigation of the performance of a solar adsorption refrigerator using a flat-plate solar collector. The values of glass cover and absorber plate temperatures obtained from numerical solutions of heat balance equations are used to predict the solar coefficient of performance of the solar refrigerator. The simulation technique takes into account the variations of ambient temperature and solar radiation along the day. The effects of optical parameters of the glass cover such as absorption and transmission coefficients on glass cover and absorber plate temperatures and consequently on the coefficient of performance are analyzed. As a result, it is found that the absorber plate temperature is less to the absorption coefficient than the cover glass temperature. Also the thermal radiation exchange has more effect on the cover glass temperature. The higher values of COP are obtained between 11 and 13 h during the morning when the temperatures of the absorber plate and the ambient temperatures increase. Moreover the COP increases with the coefficient of transmission of the glass cover but the main parameter acting on the variations of the COP remains the temperature of the evaporator.

  4. Solar energy dryer kinetics using flat-plate finned collector and forced convection for potato drying

    Science.gov (United States)

    Batubara, Fatimah; Misran, Erni; Dina, Sari Farah; Heppy

    2017-06-01

    Research on potato drying using the indirect solar dryer with flat-plate finned collector and forced convection has been done. The research was conducted at the outdoor field of Laboratory of Institute for Research and Standardization of Industry on June 14th-23rd, 2016 from 9:00 am to 4:00 pm. This research aims to obtain the drying kinetics model of potato (Solanumtuberosum L.) using an indirect solar dryer's (ISD) with flat plate-finned collector and forced convection. The result will be compared to the open sun drying (OSD) method. Weather conditions during the drying process took place as follows; surrounding air temperature was in the range 27 to 34.7 °C, relative humidity (RH) 29.5 to 61.0% and the intensity of solar radiation 105.6 to 863.1 Watt/m2. The dried potato thicknesses were 1.0 cm, 1.5 cm and 2.0 cm, with the average initial water content of 76.46%. The average temperature in the collector chamber ranged from 42.2 to 57.4 °C and the drying chamber was at 46.2 °C. The best drying result was obtained from a sample size of 1 cm thickness using the IDS method with an average drying rate of 0.018 kg H2O per kg dry-weight.hour and the water content was constant at 5.02% in 21 hours of drying time. The most suitable kinetics model is Page model, equation MR = exp (-0.049 t1,336) for 1.0 cm thickness, exp (-0.066 t1,222) for 1.5 cm thickness and exp (-0.049 t1,221) for 2.0 cm thickness. The quality of potato drying using ISD method is better than using OSD which can be seen from the color produced.

  5. The effect of contact spacing on the efficiency of flat plate solar collector plates

    Science.gov (United States)

    Schneider, G. E.; Crha, S.

    1984-01-01

    Rather than use a continuous weld or solder for thermal contact in the attachment of an extended surface to an energy removal tube, attention is given to the use of discontinuous attachment through the uniform distribution of finite regions of contact. This scheme is applied to a solar energy collection system in which it was thought capable of yielding fabrication and reliability improvements. A nondimensional formulation and numerical solution of FEM modeling yields the sensitivity of collector thermal performance to weld-solder joint dimensions. The discontinuous weld is found to significantly degrade system performance in proportion to the fin surface Biot modulus, with the controlling parameter (with respect to weld dimensions) being the perimeter length at the weld location of contact.

  6. An effective simulation model to predict and optimize the performance of single and double glaze flat-plate solar collector designs

    OpenAIRE

    Kaplanis, S.; Kaplani, E.

    2012-01-01

    This paper outlines and formulates a compact and effective simulation model, which predicts the performance of single and double glaze flat-plate collector. The model uses an elaborated iterative simulation algorithm and provides the collector top losses, the glass covers temperatures, the collector absorber temperature, the collector fluid outlet temperature, the system efficiency, and the thermal gain for any operational and environmental conditions. It is a numerical approach based on simu...

  7. Status of the NASA-Lewis flat-plate collector tests with a solar simulator

    Science.gov (United States)

    Simon, F. F.

    1974-01-01

    Simulator test results of 15 collector types are reported. Collectors are given performance ratings according to their use for pool heating, hot water, absorption A/C or heating and solar Rankine machines. Collectors found to be good performers in the above categories, except for pool heating, were a black nickel coated, 2 glass collector, and a black paint 2 glass collector containing a mylar honeycomb. For pool heating, a black paint, one glass collector was found to be the best performer. Collector performance parameters of 5 collector types were determined to aid in explaining the factors that govern performance. The two factors that had the greatest effect on collector performance were the collector heat loss and the coating absorptivity.

  8. Standard Test Method for Water Penetration of Flat Plate Solar Collectors by Uniform Static Air Pressure Difference

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1986-01-01

    1.1 This test method covers the determination of the resistance of flat plate solar collectors to water penetration when water is applied to their outer surfaces with a static air pressure at the outer surface higher than the pressure at the interior of the collector. 1.2 This test method is applicable to any flat plate solar collector. 1.3 The proper use of this test method requires a knowledge of the principles of pressure and deflection measurement. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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. Specific precautionary information is contained in Section 6.

  9. Exergy efficiency analysis of a flat plate solar collector using graphene based nanofluid

    Science.gov (United States)

    Said, Z.; Alim, M. A.; Janajreh, Isam

    2015-10-01

    The thermal efficiency of a flat plate solar thermal collector is largely affected by the thermal conductivity of the fluid used. In this paper, we theoretically analyzed the heat transfer performance, the entropy generation rate, and the exergy efficiency of the two different graphene based nanofluids (graphene/Acetone and graphene/water). From the analyses, it is revealed that by inserting a small amount of graphene nanoparticles in water, exergy efficiency could be enhanced by 21%, comparing to conventional fluids and entropy generation is decreased by 4%. However, the graphene/water nanofluid shows a lower entropy generation. This characteristic suggests that graphene/water nanofluid is a better candidate for flat solar thermal application.

  10. Numerical analysis of flow and heat transfer behavior in fin-tube flat-plate solar collector

    Institute of Scientific and Technical Information of China (English)

    Namory Camara; LU Hui-lin

    2007-01-01

    Temperature distribution over the absorber plate of a parallel flow flat-plate solar collector is numerically analyzed. The governing differential equations with boundary conditions are solved numerically using fluent software. Effects of the inlet mass flux, inlet temperature and tube spacing on velocity and temperature distributions are discussed. Numerical results show that the distributions of velocity and temperature of fluid is unsymmetrical inside pipe.

  11. 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

  12. Evaluation of flat-plate collector efficiency under controlled conditions in a solar simulator

    Science.gov (United States)

    Johnson, S. M.; Simon, F. F.

    1976-01-01

    The measured thermal efficiencies of 35 collectors tested with a solar simulator, along with the correlation equations used to generalize the data, are presented in this report. The single correlation used is shown to apply to all the different types of collectors tested, including one with black paint and one cover, one with a selective surface coating and two covers, and an evacuated-tube collector. The test and correlation technique is also modified by using a shield so that collectors larger than the simulator test area can also be tested. This technique was verified experimentally for a shielded collector for which the collector shielded area was 31% of the solar simulator radiation area. A table lists all the collectors tested, the collector areas, and the experimental constants used to correlate the data for each collector.

  13. 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

  14. 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

  15. Experimental Study on Performance of a Box Solar Cooker with Flat Plate Collector to Boil Water

    Science.gov (United States)

    Sitepu, T.; Gunawan, S.; Nasution, D. M.; Ambarita, H.; Siregar, R. E. T.; Ronowikarto, A. D.

    2017-03-01

    In this study, a flat plate type solar cooker is tested by exposing in solar irradiation. The objective is to examine the performance of solar cooker in boiling water. The solar cooker is a box type with collector area and height are 100 × 100 cm and 40 cm, respectively. Vessel for water is made of aluminum plate with diameter and height of 22 cm and 15 cm. The experiments are performed by varying mass of the water. It is 2 kg and 4 kg, respectively. Every experiment starts from 10:00 AM until the boiling temperature is reached. The parameters measured are radiance intensity, ambient and solar box cooker temperatures, and wind speed. The results show that the duration of water heating up to 100°C with water mass 2 kg within 2 hours 45 minutes and water mass 4 kg within 3 hours 17 minutes. The maximum temperatur of solar box cooker is 117°C at 12:56 PM and maximum efficiency is 46.30%. The main conclusion can be drawn here is that a simple solar box cooker can be used to boil water.

  16. 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......-plate collectors used as the test section. Two correlations were proposed for the Nusselt number as a function of the Reynolds number and the Prandtl number based on hydraulic diameter for various heat fluxes. The temperature distribution along the finned tube for the fluid and the wall were also illustrated....

  17. Analysis of the Thermal Performance of a Solar Water Heating System with Flat Plate Collectors in a Temperate Climate

    OpenAIRE

    Ayompe, Lacour; DUFFY Aidan

    2013-01-01

    The thermal performance of a solar water heating system with 4 m2 flat plate collectors in Dublin, Ireland is presented in this paper. The experimental setup consisted of a commercially available forced circulation domestic scale system fitted with an automated sub‐system that controlled hot water draw‐offs and the operation of an auxiliary immersion heater. The system was tested over a year and the maximum recorded collector outlet fluid temperature was 70.4 oC while the maximum water temper...

  18. Experimental investigation on a flat plate solar collector using Al2O3 Nanofluid as a heat transfer agent

    Directory of Open Access Journals (Sweden)

    Abbas Sahi Shareef, Mohammed Hassan Abbod, Sura Qahtan Kadhim

    2015-01-01

    Full Text Available This work introduces experimental results of an Al2O3 -water based nanofluid as the working fluid for flat tube in plate type solar collector. Experimental test setup comprises a solar collector, closed working fluid system and measurement devices (flow meter, thermocouples, temperature meter and digital solar power meter. The Base case was experimented with di-ionized water with a flow rate of 1 lpm. In second case, Al2O3 nanoparticles are mixed in di-ionized water to get nanofluid of 0.5% volume fraction concentration. The maximum difference between outlet and inlet temperatures of the solar collector was 14.4 ̊ C with the solar irradiance of about 788 W/m2 while in case of water the maximum temperatures difference was 10.7 ̊ C with a solar irradiance of about 781 W/m2.

  19. Solar Collectors

    Science.gov (United States)

    1980-01-01

    Solar Energy's solar panels are collectors for a solar energy system which provides heating for a drive-in bank in Akron, OH. Collectors were designed and manufactured by Solar Energy Products, a firm established by three former NASA employees. Company President, Frank Rom, an example of a personnel-type technology transfer, was a Research Director at Lewis Research Center, which conducts extensive solar heating and cooling research, including development and testing of high-efficiency flat-plate collectors. Rom acquired solar energy expertise which helped the company develop two types of collectors, one for use in domestic/commercial heating systems and the other for drying grain.

  20. Modelling and control of Base Plate Loading subsystem for The Motorized Adjustable Vertical Platform

    Science.gov (United States)

    Norsahperi, N. M. H.; Ahmad, S.; Fuad, A. F. M.; Mahmood, I. A.; Toha, S. F.; Akmeliawati, R.; Darsivan, F. J.

    2017-03-01

    Malaysia National Space Agency, ANGKASA is an organization that intensively undergoes many researches especially on space. On 2011, ANGKASA had built Satellite Assembly, Integration and Test Centre (AITC) for spacecraft development and test. Satellite will undergo numerous tests and one of it is Thermal test in Thermal Vacuum Chamber (TVC). In fact, TVC is located in cleanroom and on a platform. The only available facilities for loading and unloading the satellite is overhead crane. By utilizing the overhead crane can jeopardize the safety of the satellite. Therefore, Motorized vertical platform (MAVeP) for transferring the satellite into the TVC with capability to operate under cleanroom condition and limited space is proposed to facilitate the test. MAVeP is the combination of several mechanisms to produce horizontal and vertical motions with the ability to transfer the satellite from loading bay into TVC. The integration of both motions to elevate and transfer heavy loads with high precision capability will deliver major contributions in various industries such as aerospace and automotive. Base plate subsystem is capable to translate the horizontal motion by converting the angular motion from motor to linear motion by using rack and pinion mechanism. Generally a system can be modelled by performing physical modelling from schematic diagram or through system identification techniques. Both techniques are time consuming and required comprehensive understanding about the system, which may expose to error prone especially for complex mechanism. Therefore, a 3D virtual modelling technique has been implemented to represent the system in real world environment i.e. gravity to simulate control performance. The main purpose of this technique is to provide better model to analyse the system performance and capable to evaluate the dynamic behaviour of the system with visualization of the system performance, where a 3D prototype was designed and assembled in Solidworks

  1. Use of mirrors with plate collectors; Uso de espejos con colectores planos

    Energy Technology Data Exchange (ETDEWEB)

    Follari, J. A.; Odicino, L. a.; Perello, A. D.; Fasulo, A. J.

    2004-07-01

    We analyze the solar radiative contribution that a fixed flat mirror cam perform on a collector, also fixed in its position , if that mirror is put above the collector. Various angles, be they for the mirror or for the collector are investigated, in order to determine their practical usefulness as a function of the real effective contribution they provide. First the theoretical contribution is calculated using approximative formulae, then the effective contribution to a solar collector connected to a thermal reservoir mow forming a solar heater, is measured. The field of applicability of this device is analyzed considering the cost of collector and the mirror, the usefulness depending on the angle between the collector and the horizontal plain. (Author)

  2. Solar tests of aperture plate materials for solar thermal dish collectors

    Science.gov (United States)

    Jaffe, L. D.

    1984-11-01

    If a malfunction occurs in a solar thermal point-focus distributed receiver power plant while a concentrator is pointed at the sun, motion of the concentrator may stop. As the sun moves relative to the earth, the spot of concentrated sunlight then slowly walks off the receiver aperture, across the receiver face plate, and perhaps across adjacent portions of the concentrator. Intense local heating by the concentrated sunlight may damage or destroy these parts. The behavior of various materials under conditions simulating walk-off of a parabolic dish solar collector were evaluated. Each test consisted of exposure to concentrated sunlight at a peak flux density of about 7000 kW/square meter for 15 minutes. Types of materials tested included graphite, silicon carbide, silica, various silicates, alumina, zirconia, aluminum, copper, steel, and polytetrafluroethylene. The only material that neither cracked nor melted was grade G-90 graphite. Grade CS graphite, a lower cost commercial grade, cracked half-way across, but did not fail apart. Both of these grades are medium-grain extruded graphites. A graphite cloth (graphitized polyacrylonitrile) showed fair performance when tested as a single thin ply; it might be useful as a multi-ply assembly. High purity slipcast silica showed some promise also.

  3. Solar tests of aperture plate materials for solar thermal dish collectors

    Science.gov (United States)

    Jaffe, L. D.

    1984-01-01

    If a malfunction occurs in a solar thermal point-focus distributed receiver power plant while a concentrator is pointed at the sun, motion of the concentrator may stop. As the sun moves relative to the earth, the spot of concentrated sunlight then slowly walks off the receiver aperture, across the receiver face plate, and perhaps across adjacent portions of the concentrator. Intense local heating by the concentrated sunlight may damage or destroy these parts. The behavior of various materials under conditions simulating walk-off of a parabolic dish solar collector were evaluated. Each test consisted of exposure to concentrated sunlight at a peak flux density of about 7000 kW/square meter for 15 minutes. Types of materials tested included graphite, silicon carbide, silica, various silicates, alumina, zirconia, aluminum, copper, steel, and polytetrafluroethylene. The only material that neither cracked nor melted was grade G-90 graphite. Grade CS graphite, a lower cost commercial grade, cracked half-way across, but did not fail apart. Both of these grades are medium-grain extruded graphites. A graphite cloth (graphitized polyacrylonitrile) showed fair performance when tested as a single thin ply; it might be useful as a multi-ply assembly. High purity slipcast silica showed some promise also.

  4. Optimization of Thin-Film Transparent Plastic Honeycomb Covered Flat-Plate Solar Collectors. Phase 2.

    Science.gov (United States)

    2007-11-02

    the former preferred for high-temperature collectors since it is opaque in the longer wavelength region and hence improves the efficiency by reducing re...different temperature regions . The analyses show that collectors equipped with Lexan honeycomb are more cost ef- fective than comparable nonhoneycomb...Contract E(04-3)- 1081. " REFERENCES 1. Francia , G., "A New Collector of Solar Energy -- Theory and Experimental Verification -- Calculation of the

  5. Coaxial extrusion conversion concept for polymeric flat plate solar collectors. Final technical report, September 30, 1978-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Rhodes, R.O.; Chapman, N.J.; Chao, K.C.; Sorenson, K.F.

    1980-01-01

    This study investigated materials and processes for fundamental improvements in flat-plate solar collector cost and performance. The goal was to develop a process for direct conversion of inexpensive raw materials into a completed solar collector unit, without labor intensive assembly operations. It was thought that materials carefully matched to the process and end-use environment would substantially reduce collector costs, as compared to conventional industry practice. The project studied the feasibility of a cost-effective, glazed solar collector, with low labor input, utilizing a coaxial extrusion of compatible polymeric materials. This study evaluated all considered materials for the desired application. In addition, there was a trial extrusion of the leading candidate glazing and absorber materials, which resulted in successfully performing a coaxial extrusion of one cell. At the time the study was conducted, there were no materials available that met the necessary requirements for the specified utilization. It was recommended that, if potentially compatible materials become available, further investigation into the suitability of those materials be researched. Then, if a suitable material was found, proceeding into Phase II would be recommended.

  6. 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.

  7. Comparison of the effects of Al2O3 and CuO nanoparticles on the performance of a solar flat-plate collector

    Science.gov (United States)

    Munuswamy, Dinesh Babu; Madhavan, Venkata Ramanan; Mohan, Mukunthan

    2015-12-01

    To improve the efficiency of solar flat-plate collectors further, a study had been carried out wherein the conventional working fluid was replaced by nanofluids. A 25-L/day solar flat-plate water heater with collector area of 0.5 {m}^2 has been designed and fabricated. The thermosyphon system of the solar water heater was monitored at 15 locations using T-type thermocouples. Alumina and CuO nanoparticles were synthesized and characterized using Brunauer-Emmett-Teller and X-ray diffraction techniques and dispersed using ultrasonic mechanism. To stabilize the system at an optimum level, the collector is operated with volume fractions of 0.2% and 0.4% of synthesized Al2O3 and CuO nanoparticles mixed with distilled water and used in the solar flat-plate collector. The temperature profile was compared with different volume fractions of the nanoparticles in the flowing medium. Enhanced heat transfer was observed in the solar flat-plate collector using nanoparticles, and hence, it is inferred that addition of nanoparticles improves the efficiency of the solar water heaters. This paper details the temperature profile observed in the collectors, variation of insolation over the day, and change in efficiency both on the primary side (collector) and on the secondary side (storage tank) of the solar water heater.

  8. A simulation modeling for optimization of flat plate collector design in Riyadh, Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Al Ajlan, S.A.; Al Faris, H.; Khonkar, H. [King Abdulaziz City for Science and Technology, Riyadh (Saudi Arabia). Energy Research Inst.

    2003-07-01

    A simulation of forced convection solar heated water system is presented. A computer program is developed consisting of independent subroutines, capable of handling the variation of the collector tube diameter, tube spacing, ambient conditions, material thermal properties, collector and system design optimization. The meteorological data of Riyadh were used as the input in the program to simulate the performance of the collector system. The output of the program is analyzed to optimize the system design in the Riyadh region. The results of the simulations are compared with experimental data. There is a good agreement between the predicted and measured values.(author)

  9. 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.

  10. Heat loss coefficients and effective tau-alpha products for flat-plate collectors with diathermanous covers

    Science.gov (United States)

    Hollands, K. G. T.; Wright, J. L.

    1983-01-01

    This paper presents an efficient algorithm for solving the set of nonlinear equations governing the total heat transfer across an arbitrary number of parallel flat plate solar collector covers, each of which can be partly transparent to longwave thermal radiation. The governing equations are sufficiently general to permit each cover to have asymmetric radiative properties and to account for absorption of solar energy on the individual covers. This theory is shown to be in good agreement with the approximate equations of Whillier (provided certain interpretations are placed on his quantities) and with experiments using a plastic inner cover and bounding plates of various emissivities. Using this theory, it is demonstrated that if the absorber plate has a selective surface, an inner cover transparent to long wave radiation is to be preferred over one which is opaque.

  11. Performance Evaluation of a Solar Dryer with Finny, Perforated Absorber Plate Collector Equipped with an Air Temperature Control System for Dill Drying

    Directory of Open Access Journals (Sweden)

    M Razmipour

    2015-03-01

    Full Text Available Dill is one of the most important plants in the world because of its medicinal properties and it is widely used as a vegetable in the most parts of Iran. In the present study a new solar dryer with finny, perforated absorber plate collector was utilized to dry fresh dill. The dryer was comprised of a solar collector, a product container, a fan and a drying air temperature controller. The temperature controller was used as a control system to regulate the drying air temperature. Thermal performance of the dryer with finny, perforated solar collector was compared with that of a simple flat plate solar collector at different airflow rates. The effect of drying air temperature at three levels (45, 55 and 65 °C, the product size at three lengths (3, 5 and 7 cm and two different modes of drying (mixed and indirect on the dryer performance was investigated. The results showed that the finny, perforated absorber plate solar collector could improve the thermal efficiency about 11% in comparison with the flat plate collector and the highest thermal efficiency was achieved at the maximum airflow rate. Meanwhile, increasing the air temperature and decreasing the product size caused a significant reduction in energy consumption. Solar fraction reduced by increasing the air temperature. Finally a maximum dryer efficiency of 70% was observed at air temperature of 65 oC, product size of 3 cm with mixed mode drying.

  12. 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.

  13. Flat plate collectors as facade elements for domestic hot water and heat insulation. Flachkollektoren als Fassadenelemente zur Brauchwassererwaermung und Waermedaemmung

    Energy Technology Data Exchange (ETDEWEB)

    Flamm, H.; Lochau, R.; Maeiss, M.; Schiele, J.

    1984-07-01

    In a newly constructed south-west-facade 200 m/sup 2/ of flat plate collectors were integrated as construction elements to heat domestic water. The building needs 5-10 m/sup 3/ of hot water per day, i.e. 250-500 kWh/d. The solar circuit runs with a water-glycol-mixture with a specific volume flow rate of 20-40 l/m/sup 2/h. The storage capacity is 8 m/sup 3/, i.e. 40 l/m/sup 2/ collector area. The heating system is bivalent. The total cost was DM 220.000, excepting the cost of facade construction. The observation period was 2 years. The heat flow balance was measured daily using a microprocessor. As far as the construction was concerned, there were no defects during the observation period. The rooms behind solar collectors showed no additional thermal load. The most favourable season for running solar systems is from April to September. In this period the average efficiencies were 15 to 20%, the net energy yield was 76 kWh/m/sup 2/.

  14. 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...

  15. 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 b...

  16. Development of flat-plate solar thermal collectors equipped with aerogel sandwiched absorber

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Yusuke; Izumi, Hiroaki; Aizawa, Mamoru [Dynax Corp. (Japan); Yugami, Hiroo [Graduate School of Engineering, Tohoku Univ. (Japan)

    2004-07-01

    It is important to utilize the solar energy efficiently. However, conventional solar thermal collectors have some drawbacks of high cost, heavy weight and low temperature output. These drawbacks prevent from spreading of the market of solar thermal collectors, especially in Japan. To find a solution to the problems, we propose an absorber / aerogel one-piece structure for high temperature solar thermal collectors. TiOxNy and silica aerogel were employed as a selectively solar-absorbing coating of absorber and as an optically transparent thermal insulator, respectively. Selectively solar-absorbing coatings must show lower reflectance and lower emittance. We have developed selectively solar-absorbing coatings of which optical property was {alpha} = 98.5, {epsilon} = 3 %. Wet coating of newly designed TiOxNy precursor enabled fabricating selectively solar-absorbing coatings, easily. Shrinkage of silica aerogel had to be minimized to produce an absorber / aerogel one-piece structure. Selectively solar-absorbing coatings and silica aerogel were prepared via sol-gel processing. (orig.)

  17. High performance collectors

    Science.gov (United States)

    Ogawa, H.; Hozumi, S.; Mitsumata, T.; Yoshino, K.; Aso, S.; Ebisu, K.

    1983-04-01

    Materials and structures used for flat plate solar collectors and evacuated tubular collectors were examined relative to their overall performance to project effectiveness for building heating and cooling and the feasibility of use for generating industrial process heat. Thermal efficiencies were calculated for black paint single glazed, selective surface single glazed, and selective surface double glazed flat plate collectors. The efficiencies of a single tube and central tube accompanied by two side tube collectors were also studied. Techniques for extending the lifetimes of the collectors were defined. The selective surface collectors proved to have a performance superior to other collectors in terms of the average annual energy delivered. Addition of a black chrome-coated fin system to the evacuated collectors produced significant collection efficiency increases.

  18. The Effect of the Angle of Inclination on the Efficiency in a Medium-Temperature Flat Plate Solar Collector

    Directory of Open Access Journals (Sweden)

    Orlando Montoya-Marquez

    2017-01-01

    Full Text Available In this experimental work, the effects of the inclination angle β and the (Ti − Ta/G on the efficiency and the UL-value were investigated on a medium-temperature flat plate solar collector. The experiments were based on steady-state energy balance, by heat flow calorimetry at indoor conditions and considering the standard American National Standard Institute/American Society of Heating Refrigerating and Air Conditioning Engineers (ANSI/ASHRAE 93-2010. The solar radiation was emulated by the Joule effect using a proportional integral derivative (PID control considering two conditions of the absorber temperature, Case 1: (To − Ti > 0, and Case 2: (To − Ti = 0. The inclination angles were 0°–90° and the (Ti − Ta/G were 0.044–0.083 m2·°C/W and 0.124–0.235 for Case 1 and Case 2, respectively. The variations of β and (Ti − Ta/G cause efficiency changes up to 0.37–0.45 (21.6% and 0.31–0.45 (45.0%, respectively, for Case 1. Also, the UL(β reached changes up to 10.1–12.0 W/m2·°C (19.2% and 8.4–12.0 W/m2·°C (41.7%, respectively, for Case 1. The most significant changes of UL(β/UL(90° vs. β were 8.0% at the horizontal position for Case 1, while for Case 2, the maximum change was 1.8% only. Therefore, the changes of the inclination angle cause significant variations of the convective flow patterns within the collector, which leads to considerable variation of the collector efficiency and its UL value.

  19. 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.

  20. Nitrite/nitrate detection in serum based on dual-plate generator-collector currents in a microtrench.

    Science.gov (United States)

    Gross, Andrew J; Holmes, Stephanie; Dale, Sara E C; Smallwood, Miranda J; Green, Stephen J; Winlove, C Peter; Benjamin, Nigel; Winyard, Paul G; Marken, Frank

    2015-01-01

    A dual-electrode sensor is developed for rapid detection of nitrite/nitrate at micromolar levels in phosphate buffer media and in dilute horse serum without additional sample pre-treatment. A generator-collector configuration is employed so that on one electrode nitrate is reduced to nitrite and on the second electrode nitrite is oxidised back to nitrate. The resulting redox cycle gives rise to a specific and enhanced current signal which is exploited for sensitive and reliable measurement of nitrite/nitrate in the presence of oxygen. The electrode design is based on a dual-plate microtrench (approximately 15 µm inter-electrode gap) fabricated from gold-coated glass and with a nano-silver catalyst for the reduction of nitrate. Fine tuning of the phosphate buffer pH is crucial for maximising collector current signals whilst minimising unwanted gold surface oxidation. A limit of detection of 24 μM nitrate and a linear concentration range of 200-1400 μM is reported for the microtrench sensor in phosphate buffer and dilute horse serum. Relative standard deviations for repeat measurements were in the range 1.8-6.9% (n=3) indicating good repeatability in both aqueous and biological media. Preliminary method validation against the standard chemiluminescence method used in medical laboratories is reported for nitrate analysis in serum.

  1. 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.

  2. 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

  3. Nongray-radiative and convective-conductive thermal coupling in Teflon-glazed, selective-black, flat-plate solar collectors

    Science.gov (United States)

    Edwards, D. K.; Rhee, S. J.

    1984-05-01

    An analysis is presented comparing Teflon film with glass for the inner glazing of a double-glazed selective-black, flat-plate solar collector. The effect of spacing between glazings and between the inner glazing and absorber plate is examined. It is shown that a 12.5-micron Teflon film is superior to glass for the inner glazing of a selective-black collector, because the advantage of its high solar transparency overwhelms the disadvantage of its infrared transparency. A too-small spacing between a selective-black absorber and its inner cover short-circuits the desirable thermal radiation resistance offered by a selective-black absorber plate. Account is taken of spectral variations in the radiation properties of glass, Teflon, and the absorber plate. Allowance is made for the fact that critical Rayleigh number is lower for a plastic film inner glazing than for a glass one.

  4. 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

  5. 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

  6. 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 fou

  7. 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 decrea

  8. Flat-plate solar-collector performance evaluation with a solar simulator as a basis for collector selection and performance prediction

    Science.gov (United States)

    Simon, F. F.

    1975-01-01

    This paper reports the measured thermal efficiency and evaluation of 23 collectors which differ according to absorber material (copper, aluminum, steel), absorber coating (nonselective black paint, selective copper oxide, selective black nickel, selective black chrome), type of glazing material (glass, Tedlar, Lexan, anti-reflection glass), the use of honeycomb material and the use of vacuum to prevent thermal convection losses. The collectors are given performance rankings based on noon-hour solar conditions and all-day solar conditions. The determination with the simulator of an all-day collector performance is made possible by tests at different incident angles. The solar performance rankings are made based on whether the collector is to be used for pool heating, hot water, absorption air conditioning, heating, or for a solar Rankine machine.

  9. Large-scale solar thermal collector concepts

    Science.gov (United States)

    Brantley, L. W., Jr.

    1975-01-01

    Thermal collector could be used ultimately to power steamplant to produce electricity. Collector would consist of two major subsystems: (1) series of segmented tracking mirrors with two axes of rotation and (2) absorber mounted on centrally located tower.

  10. Theoretical and experimental investigations of Chinese evacuated tubular solar collectors

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated.......Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated....

  11. 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.

  12. Development and life cycle analysis of double slope active solar still with flat plate collector

    Directory of Open Access Journals (Sweden)

    A.K. Sethi

    2014-02-01

    Full Text Available Potable water is an essential ingredient of socio-economic development and economic growth. Often water sources are brackish (i.e. contain dissolved salts and/or contain harmful bacteria and therefore cannot be used for drinking. In addition, there are many coastal locations where seawater is abundant but potable water is not available. This study is focused on a development of solar still with flat plat collector for water desalination considered for small scale applications at remote locations where only saline water is available. In this paper the cost of distilled water per kg has been calculated by using the concept of life cycle cost analysis. The pay back periods for different conditions of the distribution of distilled water, namely at the cost it is produced and at the selling price on market rate have been evaluated. The cost of water per kg is minimum Rs. 0.59, when the interest rate and the lifetime of solar still are taken as 4% and 50 years respectively. The lowest payback time 1.23 years is obtained when the selling price of water Rs. 10 per kg.

  13. 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...... collectors could raise flexibility in the control strategy of the plant. The TRNSYS-Genopt model is based on individually validated component models and collector parameters from experiments. Optimization of the cost performance of the plant has been conducted in this paper. The simulation model remains...... to be validated with annual measured data from the plant....

  14. Solar thermal collectors

    Science.gov (United States)

    Aranovitch, E.

    Thermal processes in solar flat plate collectors are described and evaluated analytically, and numerical models are presented for evaluating the performance of various designs. A flat plate collector consists of a black absorber plate which transfers absorbed heat to a fluid, a cover which limits thermal losses, and insulation to prevent backlosses. Calculated efficiencies for the collectors depend on the radiation absorbed, as well as IR losses due to natural convection, conduction, and radiation out of the collector. Formulations for the global emittance and heat transfer, as well as losses and their dependence on the Nusselt number and Grashof number are defined. Consideration is given to radiation transmission through transparent covers and Fresnel reflections at interfaces in the cover material. Finally, the performance coefficients for double-glazed and selective surface flat plate collectors are examined.

  15. The Experimental Study of Plastic Plate Solar Collector%塑料太阳能平板集热器试验研究

    Institute of Scientific and Technical Information of China (English)

    李久锋; 陈观生; 张国庆

    2015-01-01

    According to the undemanding heating rate of heat-storage solar water heater, a new type of plastic plate solar collector was designed.Under the condition of intermittent forced circulation, test on the performance of this collector was carried out and instantaneous efficiency curves were obtained.As a result, the average daily collector efficiency is 51%~55% and the temperature of tank is 45.8~50.2 ℃, which serve as a reference for the application of plastic plate solar collector.%针对蓄热型太阳能热水器对升温速率要求不高的特点,提出并研制了一种新型塑料太阳能平板集热器.在间歇性强制循环条件下,对该集热器进行性能测试,获得了瞬时效率曲线.在试验条件下,该集热器的日平均效率为51%~55%,水箱温度为45.8~50.2℃,可以为塑料平板集热器的实际应用提供依据.

  16. Solar combisystems. A comparison between vacuum tube- and flat plate collectors using measurements and simulations; Solvaermda kombisystem. En jaemfoerelse mellan vakuumroer och plan solfaangare genom maetning och simulering

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, Peter; Pettersson, Ulrik

    2002-10-01

    Two solar combisystems were mounted side by side in an outdoor test facility and continuously operated during one year. The whole year, all relevant temperatures, flow rates and environment variables were thoroughly measured. The systems were identical apart from the collectors which were a 9 m{sup 2} vacuum tube and a 12.2 m{sup 2} selective flat plate collector. A simulated space heating and tap water load of approx. 25 MWh/a was applied to each system and auxiliary heat was charged to the stores from emulated pellet boilers. Additionally, the two collectors and the store was tested separately and the systems simulated according to the CTSS principle described in ENV 12977. The aim of the project was to determine solar fractions in a solar combisystem from real measurements and to compare the two different collector types from different points of view. On the basis of the validated simulation model, the results from the long term measurements could be generalized and eight different loads were simulated. The results showed that the vacuum tubes performed 45-60% better than the flat plate per m{sup 2} depending on the load applied. The solar fractions (assuming no losses from the boiler) varied from 11% for the measured systems to approx. 30 % in a house with 25 % of the original space heating load. During the heating season, the vacuum tubes occasionally performed much worse than the flat plate due to the fact that snow and frost melted away much quicker from the flat plate. For the use of vacuum tubes in snowy regions, vertical mounting should therefore be strongly recommended.

  17. Application of sintered plate dust collector in gold mines%烧结板除尘器在黄金矿山的应用

    Institute of Scientific and Technical Information of China (English)

    郑民; 轩慎英; 刘刚

    2016-01-01

    It is always difficult for gold mine to collect dust .Inner Mongolia Pacific Mining Corporation Limited first applies sintered plate dust collectors in the crashing stage during the second phase of expansion project .The sin-tered plate dust collector occupies less space and is reliable with good dust collection effect and lower vent gas concen -tration.The paper based on technical characteristics of dust collection process and performance test results focused on the technical and economical analysis of the application of sintered plate dust collector ,expecting to provide reference of the dust collection process for gold mines .%黄金生产中的除尘问题一直受到黄金矿山企业的关注.内蒙古太平矿业有限公司二期扩建项目首次在选矿厂破碎工段采用了烧结板除尘器,其设备占地面积小、运行可靠、除尘效果好、尾气质量浓度低于排放标准.该文结合除尘工艺技术特点以及设备性能测试结果,重点对烧结板除尘器的应用进行了技术与经济分析,以期为类似黄金矿山企业除尘工艺提供参考.

  18. Decosol Project : development of solar plate collectors of high efficiency and low cost for medium temperature application; Proyecto Decosol: Desarrollo de colectores solares planos de alta eficiencia ybajo coste para aplicaciones a mediana temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Cadafalch, J.; Oliva, A.; Lavandeira, J. C.; Maestre, F.; Martinez, J. C.; Martin, J. R.; Hermo, R.

    2004-07-01

    Work that is currently being carried out by the authors in the framework of the project DECOSOL (Development of high efficiency and low cost flat plate collectors for medium temperature applications) is described in this paper. The goal of DECOSOL is to consolidate the results of previous R AND D projects conducted by the authors on the development of stagnation proof transparently insulated flat plate solar collectors prototypes, in order to end up with commercial products. (Author)

  19. 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.

  20. 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...

  1. EXPERIMENTAL RESEARCH ON A HIGH EFFICIENT FLAT PLATE SOLAR COLLECTOR%一种高效平板太阳能集热器试验研究

    Institute of Scientific and Technical Information of China (English)

    李戬洪; 江晴

    2001-01-01

    性能良好的太阳能集热器是太阳能空调的关键设备之一。广东省江门市太阳能空调系统采用了一种高效的平板集热器,其主要技术特征是增加了一块聚碳酸脂(PC)透明隔热板。本研究通过对比试验,确定了一种高效平板太阳能集热器的技术方案,并测定了瞬时效率曲线,其热损系数仅为2.90W/(m2*℃)。%Good performance of the solar collectors is one of the important elements for solar air-conditioning system.A novel type of high efficient flat plate solar collector was applied to the solar air-condition system in Jiangmen,Guangdong Province.Tests show that adding a transparent polycarbonate sheet in gap between glazing and absorber of the collector. The coefficient of the thermal loss is reduced to 2.90W/(m2℃) and the performance of the collector is improved.

  2. A facile route for controlled alignment of carbon nanotube-reinforced, electrospun nanofibers using slotted collector plates

    Directory of Open Access Journals (Sweden)

    G. R. Rakesh

    2015-02-01

    Full Text Available A facile route for controlled alignment of electrospun multiwalled carbon nanotube (MWCNT-reinforced Polyvinyl Alcohol (PVA nanofibers using slotted collector geometries has been realized. The process is based on analytical predictions using electrostatic field analysis for envisaging the extent of alignment of the electrospun fibers on varied collector geometries. Both the experimental and theoretical studies clearly indicate that the introduction of an insulating region into a conductive collector significantly influences the electrostatic forces acting on a charged fiber. Among various collector geometries, rectangular slotted collectors with circular ends showed good fiber alignment over a large collecting area. The electrospun fibers produced by this process were characterized by Atomic Force Microscopy (AFM, High Resolution Transmission Electron Microscopy (HRTEM, Scanning Electron Microscopy (SEM and Optical Microscopy. Effects of electrospinning time and slot widths on the fiber alignment have been analyzed. PVA-MWCNT nanofibers were found to be conducting in nature owing to the presence of reinforced MWCNTs in PVA matrix. The method can enable the direct integration of aligned nanofibers with controllable configurations, and significantly simplify the production of nanofibersbased devices.

  3. Simulating Single-Effect Absorption Cooling Lithium Bromide A Solar System With Flat Plate Collector And Contribute To An Office Building

    OpenAIRE

    MIRI, Mohadaseh

    2015-01-01

    Use solar energy to provide hot water consumption, space heating and cooling in recent decades is considered. In this article a model varies with time, a solar adsorption cooling system consists of a single effect lithium bromide absorption system, a flat plate collector and a storage tank or linear or parabolic simulated separately. The system for cooling an office building for hours of operation from 7 am to 18 pm is considered.About 7 kW peak cooling load occurs in July. Results obtained s...

  4. Subsystem ETH

    CERN Document Server

    Dymarsky, Anatoly; Liu, Hong

    2016-01-01

    Motivated by the qualitative picture of Canonical Typicality, we propose a refined formulation of the Eigenstate Thermalization Hypothesis (ETH) for chaotic quantum systems. The new formulation, which we refer to as subsystem ETH, is in terms of the reduced density matrix of subsystems. This strong form of ETH clarifies which set of observables defined within the subsystem will thermalize. We discuss the limits when the size of the subsystem is small or comparable to its complement. Finally, we provide numerical evidence for the proposal in case of one-dimensional Ising spin-chain.

  5. 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

  6. A 2-dimensional heat transfer analysis of a sheet-and-tube flat plate PV/thermal collector

    Energy Technology Data Exchange (ETDEWEB)

    Carriere, J.; Harrison, S. [Queen' s Univ., Kingston, ON (Canada). Dept. of Mechanical and Materials Engineering Solar Calorimetry Lab

    2008-08-15

    Temperature gradients in photovoltaic/thermal (PV/T) systems can have a significant impact on the reliability and life-span of system components. However, many simple PV/T models do not consider temperature gradients. In this study, a detailed heat transfer model was used to quantify temperature gradients within a PV/T panel in order to predict thermal and electrical performance as a function of fluid and atmospheric temperatures. The PV/T system consisted of a PV laminate bonded to a thermal collector. A glass cover was used as a secondary glazing system. The effect of increasing the thermal resistance between the various layers in the construction was evaluated in order to measure the temperature gradient through the absorber thickness. A 2-D finite difference model of heat flow in the collector was conducted in order to study the magnitude of the temperature gradient. Steady-state heat flow was calculated along the width of the system as well as between the layers. Heat flux was calculated to the centre of each element. Total absorptivity in each layer was determined by adding the absorption of each portion of the spectrum. Heat losses through the top of the collector were estimated using a 1-D analysis. The study showed that current methods of calculating fin efficiency are not valid when temperature gradients are not considered. Future studies will examine the effect of thermal expansion and shear stresses. 9 refs., 8 figs.

  7. Biological sample collector

    Science.gov (United States)

    Murphy, Gloria A.

    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.

  8. Simulation, construction and testing of a two-cylinder solar Stirling engine powered by a flat-plate solar collector without regenerator

    Energy Technology Data Exchange (ETDEWEB)

    Tavakolpour, Ali Reza; Zomorodian, Ali [Department of Mechanics of Farm Machinery Engineering, Shiraz University, Shiraz (Iran); Akbar Golneshan, Ali [Department of Mechanical Engineering, Shiraz University, Shiraz (Iran)

    2008-01-15

    In this research, a gamma-type, low-temperature differential (LTD) solar Stirling engine with two cylinders was modeled, constructed and primarily tested. A flat-plate solar collector was employed as an in-built heat source, thus the system design was based on a temperature difference of 80{sup o}C. The principles of thermodynamics as well as Schmidt theory were adapted to use for modeling the engine. To simulate the system some computer programs were written to analyze the models and the optimized parameters of the engine design were determined. The optimized compression ratio was computed to be 12.5 for solar application according to the mean collector temperature of 100{sup o}C and sink temperature of 20{sup o}C. The corresponding theoretical efficiency of the engine for the mentioned designed parameters was calculated to be 0.012 for zero regenerator efficiency. Proposed engine dimensions are as follows: power piston stroke 0.044 m, power piston diameter 0.13 m, displacer stroke 0.055 m and the displacer diameter 0.41 m. Finally, the engine was tested. The results indicated that at mean collector temperature of 110{sup o}C and sink temperature of 25{sup o}C, the engine produced a maximum brake power of 0.27 W at 14 rpm. The mean engine speed was about 30 rpm at solar radiation intensity of 900 W/m{sup 2} and without load. The indicated power was computed to be 1.2 W at 30 rpm. (author)

  9. Application of the Heat Pipe in Flat-Plate Solar Collectors%热管在平板式太阳能集热器中的应用研究

    Institute of Scientific and Technical Information of China (English)

    黄婷婷; 杜娜; 卿湛媛; 陈新; 牛宝联

    2014-01-01

    从集热器结构、传热效率、工艺、优缺点等方面详细介绍了3种常见的热管平板式太阳能集热器,它们包括蜂窝热管平板式、真空玻璃盖板热管平板式、CPC热管平板式太阳能集热器。与普通热管平板式集热器相比,3种改良方式均可降低集热器热损失,有效提高集热效率。通过对不同种类热管平板式太阳能集热器的热管种类、工作温度、结构参数等分析,发现随着温度升高,集热器集热效率下降,以及热管蒸发段长度普遍大于冷凝段长度等现象。%Three common heat pipe flat-plate solar collectors are introduced in details from the con-figuration of the collector such as heat transfer efficiency, crafts, merits, and so on, including the flat plate solar collector of honeycomb and heat pipe(HHCHP), flat plate solar collector of vacuum glass-cover board and heat pipe(HVGHP) and a compound parabolic concentrator heat pipe type solar collector(CPC). Com-pared with common heat pipe flat-plate solar collectors, these three improved programs can reduce heat loss, and effectively improve efficiency of the collector. From the analysis of different heat pipe types, oper-ating temperature, structure parameters, a phenomenon is discovered that whatever which type of heat pipe flat-plate solar collector is, as temperature goes up, the efficiency of the collectors drops and the length of evaporation is longer than the length of condensation.

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

    Energy Technology Data Exchange (ETDEWEB)

    Srithar, K. [Department of Mechanical Engineering, Thiagarajar College of Engineering, Madurai 625 015 (India); Mani, A. [Department of Mechanical Engineering, Indian Institute of Technology, Madras, Chennai 600 036 (India)

    2007-12-15

    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)

  11. Ferrocene-Boronic Acid-Fructose Binding Based on Dual-Plate Generator-Collector Voltammetry and Square-Wave Voltammetry.

    Science.gov (United States)

    Li, Meng; Xu, Su-Ying; Gross, Andrew J; Hammond, Jules L; Estrela, Pedro; Weber, James; Lacina, Karel; James, Tony D; Marken, Frank

    2015-06-10

    The interaction of ferrocene-boronic acid with fructose is investigated in aqueous 0.1 m phosphate buffer at pH 7, 8 and 9. Two voltammetric methods, based on 1) a dual-plate generator-collector micro-trench electrode (steady state) and 2) a square-wave voltammetry (transient) method, are applied and compared in terms of mechanistic resolution. A combination of experimental data is employed to obtain new insights into the binding rates and the cumulative binding constants for both the reduced ferrocene-boronic acid (pH dependent and weakly binding) and for the oxidised ferrocene-boronic acid (pH independent and strongly binding).

  12. Fin-tube solar collectors

    Science.gov (United States)

    1980-01-01

    Report presents test procedures and results of thermal-performance evaluation of seven commercial fin tube (liquid) solar collector-absorber plates. Tests were conducted indoors at Marshall Space Flight Center Solar simulator. Results are graphically shown along with supporting test data and summary, indicating efficiency as function of collector inlet temperature.

  13. Study on a Flat Plate Solar Air Collector with Baffles%扰流板型太阳能平板空气集热器集热性能

    Institute of Scientific and Technical Information of China (English)

    夏佰林; 赵东亮; 代彦军; 李勇

    2011-01-01

    对一种扰流板型太阳能平板空气集热器的集热性能进行了研究,并对各种影响集热器热性能的因素进行了分析,揭示了总热损失系数、扰流板肋片效率、流道内空气流速和扰流板的间距对效率因子和热迁移因子的影响机理.获得了扰流板型太阳能平板空气集热器的集热效率理论表达式,为此类太阳能空气集热器的设计及应用提供了参考.%A flat plate solar air collector with baffles was studied. Several factors that have influence on the thermal performance of the solar collectors were analyzed. The paper investigated the relations between the efficiency factor, the heat-removal factor of the solar air collector and the total heat loss coefficient, baffles fin efficiency, air velocity inside the flow channel, the space between baffles, and the height of baffles. Also, the time constant of the collectors was studied. The theoretical formula of the collector's thermal efficiency was obtained, which can be used for design and application of such kind of collectors.

  14. Enhancing the Heat Transfer of Flat-plate Solar Collector%平板太阳能集热器强化传热应用研究进展∗

    Institute of Scientific and Technical Information of China (English)

    吉佳文; 王文志; 李金凯; 段广彬; 刘宗明

    2016-01-01

    As the key part of the flat-plate solar water heater,the heat transfer performance of the collector is determined by the heat collector efficiency.The flat-plate solar collector with typical structure and heat transfer mode are described.Meanwhile the present technologies for enhancing heat transfer of flat-plate solar collector and the fu-ture development trend are reviewed and discussed.%集热器作为平板太阳能热水器的关键部分,其传热性能决定着热水器集热效率的高低。介绍了平板太阳能集热器的典型结构以及传热方式,综述了平板太阳能集热器目前所采用的强化传热方式及今后强化传热技术的发展趋势。

  15. Therminol VP-1导热油平板太阳能集热器的热工性能测试实验%Therminol VP-1 Heat Transfer Fluid Plate Solar Collector Thermal Performance Test

    Institute of Scientific and Technical Information of China (English)

    唐千喻; 王华; 王辉涛; 卿山

    2011-01-01

    Due to the advantages and disadvantages ofstructure of solar collectors, developed a new type of heat transfer fluid plate solar collectors, and test its performance. Measured results, it can achieve the thermal efficiency of 0.45, higher than the conventional flat solar collector Shows that the heat transfer fluid superior performance, have a good prospect.%针对市场上的平板太阳能集热器结构的优缺点,研制了新型的导热油平板太阳能集热器,并测试其性能.实测结果为,热效率能达到0.45,比普通平板集热器高.表明该导热油平板太阳能集热器性能优越,有很好的应用前景.

  16. MATHEMATICAL MODELLING AND PERFORMANCE ANALYSIS OF DIFFERENT SOLAR AIR COLLECTORS

    Directory of Open Access Journals (Sweden)

    M. A. Karim

    2015-11-01

    Full Text Available The purpose of using solar air collectors is to raise the atmospheric air temperature to a temperature which can be used for various low and medium temperature applications. Collector, absorber and airflow arrangement are the most important components in the solar air collector. The performance of the collector depends on its heat loss and the absorber area that is in contact with the airflow. This study involves the theoretical simulation of the effect of mass flow rate on the performance, for flat plate and v-groove collectors that are in single and double pass configurations. Results show that the v-groove double pass air collector has the highest efficiency value of 56% at . The performance is greater than flat plate double pass collector, which has an efficiency of 54% under the same operating conditions. KEYWORDS: solar air collector; flat plate collector (fpc; v-groove collector; efficiency; single pass; double pass

  17. Cysteine-cystine redox cycling in a gold-gold dual-plate generator-collector microtrench sensor.

    Science.gov (United States)

    Hammond, Jules L; Gross, Andrew J; Estrela, Pedro; Iniesta, Jesus; Green, Stephen J; Winlove, C Peter; Winyard, Paul G; Benjamin, Nigel; Marken, Frank

    2014-07-15

    Thiols and disulfides are ubiquitous and important analytical targets. However, their redox properties, in particular on gold sensor electrodes, are complex and obscured by strong adsorption. Here, a gold-gold dual-plate microtrench dual-electrode sensor with feedback signal amplification is demonstrated to give well-defined (but kinetically limited) steady-state voltammetric current responses for the cysteine-cystine redox cycle in nondegassed aqueous buffer media at pH 7 down to micromolar concentration levels.

  18. Numerical Simulation Study on Flat Plate Solar Collectors in Series - connected System%直流式系统中平板型太阳能集热器数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    倪贝; 丁昀; 杨庆

    2011-01-01

    As it is difficult to solve the problem of unsteady - state heat transfer in theory, study of flat plate solar collectors in series -connected system with intermittent output is conducted by numerical simulation.Under the unsteady - state heat transfer condition, the impact of the diameter and center distance of solar collectors on the instantaneous collector efficiency and water production rate per square meter are discussed respectively.The results show that flat cartridge collector performed high effeciency.And under the same conditions, the larger the diameter of collector is, the higher efficiency will be.These can be used for optimizing design parameters of flat plate solar collectors.%由于非稳态传热问题通过理论计算得到解析解较困难,本文运用数值模拟方法研究定温放水型直流式系统中平板型太阳能集热器的工作状况,讨论了集热器的管径和管中心距在非稳态传热条件下对集热器的效率和每平方米产水量的影响.可得到结论扁盒式集热器具有较高效率;相同条件下,管径越大集热器效率越高.该结果有利于优化直流式平板集热器的设计参数.

  19. Experimental Analysis of Serpentine-flow Flat-plate Solar Collector%蛇形管平板式太阳能集热器的试验研究

    Institute of Scientific and Technical Information of China (English)

    李俊贤; 王辉涛; 王华; 包桂蓉

    2011-01-01

    A serpentine-flow flat-plate solar collector of small volume and large temperature difference is designed and developed in order to explore the fiat-plate solar collector used in high temperature situation. And experiment of stagnation and instantaneous efficiency is carried out. The results shown that stagnation temperature can reach 170.2 ℃ and heat loss coefficient is 5. 239 W/( m2 · ℃ ). Efficiency of solar collector between 52% —55% when inlet temperature of working fluid is 70 ℃. By comparison the temperature trend of various parts of the collector the corrective measure is proposed to improve performance of serpentine-flow fiat-plate solar collector in high temperature conditions.%为了探寻一种在中高温场合使用的平板式太阳能集热器,设计和开发了小流量、大温差的蛇形管平板式太阳能集热器,并进行了空晒试验和瞬时效率试验.试验结果表明:集热器的空晒温度可达170.2℃,热损系数为5.239 W/(m2·℃),载热工质进口温度70℃时效率52%-55%.通过对集热器各部分温度变化趋势的比较,提出改进措施,以提高蛇形管平板式集热器在中高温工况下的集热性能.

  20. Ceramic Plate Solar Collector and Column Pile Structure Ceramic Solar Roof%陶瓷太阳板与锚桩结构陶瓷太阳能房顶的应用

    Institute of Scientific and Technical Information of China (English)

    孙启正; 许建华

    2012-01-01

    陶瓷太阳板以普通瓷土、工业废弃物为原料,具有制造工艺简单、生产耗能少、成本低、寿命长、效率高的优点;锚桩陶瓷太阳能房顶与原房顶共用结构层、保温层、防水层,结构简单、与建筑一体化、与建筑同寿命,为建筑物提供热水、取暖、空调的功能。%Ceramic plate solar collector, manufactured by common porcelain clay and industrial waste,has a lot of advantages such as simple process,low energy consumption,low cost,long life, high efficiency etc. Ceramic plate solar collector roof share the structure layer,insulation layer and waterproof layer with the origin roof. The roof has a simple structure, integration and same life with the building. Ceramic plate solar collector roof can supply hot water, heating and air condition to the building.

  1. Desiccant cooling using unglazed transpired solar collectors

    Science.gov (United States)

    Pesaran, A. A.; Wipke, K.

    1992-05-01

    The use of unglazed solar collectors for desiccant regeneration in a solid desiccant cooling cycle was investigated because these collectors are lower in cost than conventional glazed flat-plate collectors. Using computer models, the performance of a desiccant cooling ventilation cycle integrated with either unglazed transpired collectors or conventional glazed flat-plate collectors was obtained. We found that the thermal performance of the unglazed system was lower than the thermal performance of the glazed system because the unglazed system could not take advantage of the heat of adsorption released during the dehumidification process. For a 3-ton cooling system, although the area required for the unglazed collector was 69 percent more than that required for the glazed collector, the cost of the unglazed collector array was 44 percent less than the cost of the glazed collector array. The simple payback period of the unglazed system was half of the payback period of the glazed collector when compared to an equivalent gas-fired system. Although the use of unglazed transpired collectors makes economic sense, some practical considerations may limit their use in desiccant regeneration.

  2. 混合工质太阳能平板热管集热器的传热性能%Heat Transfer Performance ofthe Flat Plate Heat Pipe Solar Collector with Mixture Working Fluid

    Institute of Scientific and Technical Information of China (English)

    杜胜华; 苏海鹏

    2014-01-01

    介绍了平板热管的基本结构与原理,在分析乙二醇及其混合工质的热物理学特性的基础上,建立平板热管的物理与数学模型。采用数值计算模拟方法,分析了混合工质平板热管集热器的传热性能,研究了集热器的效率、温升和启动性能随工作时间的变化规律。研究表明,乙二醇水混合工质平板热管集热器适宜于低温寒冷地区,具有较高的集热性能。%The basic structure and principle of flat plate heat pipe were introduced based on thermal physics characteristics analysis of ethylene glycol and mixtures , physical and mathematical models of flat plate heat pipe were established.By the numerical simulation method , the heat transfer performance of the flat heat pipe heat collector with mixture working fluid was analyzed , and the efficiency , temperature collector up and starting performance by time were studied.It showed that flat heat pipe heat collector with ethylene glycol water mixture was suitable for cold area , and the heat collecting performance was high.

  3. Qualification test and analysis report: Solar collectors

    Science.gov (United States)

    1978-01-01

    Test results show that the Owens-Illinois Sunpak TM Model SEC 601 air-cooled collector meets the national standards and codes as defined in the Subsystem Peformance Specification and Verification Plan of NASA/MSFC, dated October 28, 1976. The program calls for the development, fabrication, qualification and delivery of an air-cooled solar collector for solar heating, combined heating and cooling, and/or hot water systems.

  4. Preliminary design package for Sunair SEC-601 solar collector

    Science.gov (United States)

    1978-01-01

    The preliminary design of the Owens-Illinois model Sunair SEC-601 tubular air solar collector is presented. Information in this package includes the subsystem design and development approaches, hazard analysis, and detailed drawings available as the preliminary design review.

  5. Effects of Key Parameters on Thermal Performance of Solar Flat-Plate Collector%太阳能平板集热器关键参数对其热性能的影响

    Institute of Scientific and Technical Information of China (English)

    车永毅; 厚彩琴

    2016-01-01

    为了提升太阳能在建筑能源供给体系中的比重,形式多样的太阳能集热设备及其系统在建筑领域得到了广泛应用。基于机理分析法,建立了具有单层玻璃盖板的管板式太阳能平板集热器的稳态传热模型。并且针对集热管间距、集热管内径、工质入口温度和工质质量流量等关键参数对集热器集热效率的影响特性进行了数值模拟与分析。结果表明,建立的该稳态传热模型是可行的;此外,在其余参数值保持不变的情况下,减小集热管间距或增加集热管内径均可使集热器瞬时效率增大;增大工质入口温度会导致集热器瞬时效率下降;而增大工质质量流量会提升集热器瞬时效率。这些结论对于太阳能平板集热器在太阳能建筑一体化的实际应用中,具有一定的参考作用。%In order to improve the proportion of solar energy in building energy supply system, various forms of solar heat collection equipment and systems in the construction field has been widely used. Based on the mechanism analysis method, one steady-state heat transfer model of the single glass cover flat-plate collector is built. The numerical simulation and analysis of the effect of the key parameters including col-lector tube spacing, collector tube diameter, and inlet temperature and inlet mass flow rate of the working fluid on heat collection efficiency of the collector is carried out. The results show that the steady-state heat transfer model is feasible;and in the case of the same parameters, either reducing the collector tube spacing or increasing the collector tube diameter can increase the instantaneous efficiency of the collector; the instantaneous efficiency of the collector decline with the increase of inlet temperature of the working fluid. However, increasing the mass flow rate at the entrance can improve the instantaneous efficiency of the collector. These conclusions have a certain

  6. Solar Heating Systems with Evacuated Tubular Solar Collector

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1998-01-01

    , 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......-plate collectors. For solar heating plants, the yearly energy output from these evacuated tubular collectors is about 40%-90% higher than the output from typical flat-plate collectors at an operation temperature of about 50°C.......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...

  7. Indoor thermal performance evaluation of Daystar solar collector

    Science.gov (United States)

    Shih, K., Sr.

    1977-01-01

    The test procedures used and results obtained from a test program to obtain thermal performance data on a Daystar Model 21B, S/N 02210, Unit 2, liquid solar collector under simulated conditions are described. The test article is a flat plate solar collector using liquid as a heat transfer medium. The absorber plate is copper and coated with black paint. Between the tempered low iron glass and absorber plate is a polycarbonate trap used to suppress convective heat loss. The collector incorporates a convector heat dump panel to limit temperature excursions during stagnation. The following tests were conducted: (1) collector thermal efficiency; (2) collector time constant; (3) collector incident angle modifier; (4) collector heat loss coefficient; and (5) collector stagnation.

  8. Weathering of a liquid solar collector

    Science.gov (United States)

    1980-01-01

    Commercially available flate plate hot water solar collector is characterized in report that presents 10 month weathering study of system. Collector efficiency was calculated and plotted from measurements of fluid temperature and flow rate, ambient temperature and solar flux. Windspeed and wind direction were also measured during tests.

  9. 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...... 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. It is important to characterize microclimatic conditions in the collector, and at the Department of Buildings and Energy work is carried out with the improvement of a computer model. As a tool the computer model will be useful in developing guidelines to achieve the most favourable...

  10. The multiple layer solar collector

    Science.gov (United States)

    Kenna, J. P.

    1983-01-01

    An analytical model is developed for obtaining numerical solutions for differential equations describing the performance of separate layers in a multiple layer solar collector. The configurations comprises heat transfer fluid entering at the top of the collector and travelling down through several layers. A black absorber plate prevents reemission of thermal radiation. The overall performance is shown to depend on the number of layers, the heat transfer coefficient across each layer, and the absorption properties of the working fluid. It is found that the multiple layer system has a performance inferior to that of flat plate selective surface collectors. Air gaps insulating adjacent layers do not raise the efficiency enough to overcome the relative deficiency.

  11. 平板太阳能集热器热性能数学建模及模拟%Mathematical Modeling and Simulation of Thermal Properties of Flat-Plate Solar Collector

    Institute of Scientific and Technical Information of China (English)

    卢郁; 于洪文; 丁海成; 张艳丽; 刘宗明

    2013-01-01

    以平板太阳能集热器作为研究对象,通过对平板太阳能集热器热性能进行理论推导,引入效率因子,构建更为准确、便捷的平板集热器的数学模型,进行计算机程序模拟.根据模拟数据得出吸热体板芯几何结构、板芯用材对平板太阳能集热器性能的影响.在不降低集热器效率因子的情况下,使翅片的单位面积质量降低45.8%;在材料消耗相同的情况下,集热器效率因子提高了0.03.%Taking a flat-plate solar collector as research object and introducing an efficiency factor, we establish a mathematical model for the collector after theoretically deriving out the thermal properties of it, and numerically simulate it according to this model. Simulation results show that the mass per unit area of the collector drops 45. 8% with the same efficiency factor and the efficiency factor increasesby 0.03 with the same material consumption.

  12. 微热管阵列平板太阳能集热器中空保温层厚度优化%Optimization of hollow insulation layer for flat plate solar collector based on micro heat pipe array

    Institute of Scientific and Technical Information of China (English)

    邓月超; 赵耀华; 全贞花; 刘中良

    2015-01-01

    In this paper, a three-dimensional CFD numerical model of heat transfer and fluid flow was developed to simulate the thermal performance of the novel flat plate solar collector based on a micro heat pipe array to provide a theoretical basis for the structure improvement and optimization of the collector. The simulation of the novel collector with water flow included the CFD modeling of solar irradiation and the modes of mixed convection and radiation heat transfer between the absorber plate and glass cover, as well as the heat transfer in the circulating water inside the heat exchanger and conduction of the insulation. The fluid flow and heat transfer in the computational domain satisfied the continuity equation, the momentum equation, and the energy equation. The standardk-ε two-equation turbulence model was used in this paper. In order to predict the direct illumination energy source that results from incident solar radiation and the radiation field inside the collector, the discrete ordinate radiation model with a solar ray-tracing model was used. A commercial computational fluid dynamics program (Fluent 6.3 CFD software) was used to solve the coupled fluid flow, heat transfer, and the radiation equation. The solver used is the segregated solver. Body Force Weighted was selected as the discretization method for pressure, and the SIMPLE algorithm was used to resolve the coupling between pressure and velocity. The discretization methods for the solving of momentum, energy, radiation, and turbulence were second order upwind. The thermal performance could be achieved by simulation results under different conditions. Then, the experimental and numerical results were compared to validate the prediction of the CFD model. The results showed that the numerical results of the thermal efficiency of the novel collector were in reasonable agreement with the experimental data. The validated CFD model was used to analyze the properties of the insulation layer. First, the

  13. Solar thermal collectors using planar reflector

    Science.gov (United States)

    Espy, P. N.

    1978-01-01

    Specular reflectors have been used successfully with flat-plate collectors to achieve exceptionally high operating temperatures and high delivered energy per unit collector area. Optimal orientation of collectors and reflectors can result in even higher performance with an improved relationship between energy demand and supply. This paper reports on a study providing first order optimization of collector-reflector arrays in which single- and multiple-faceted reflectors in fixed or singly adjustable configurations provide delivered energy maxima in either summer or winter.

  14. MINICHANNEL-TUBE SOLAR THERMAL COLLECTORS FOR LOW TO MEDIUM TEMPERATURE APPLICATIONS

    OpenAIRE

    Duong, Thuc

    2015-01-01

    Novel minichannel-tube solar thermal collectors for low to medium temperature applications are introduced. Two types of minichannel solar thermal collectors are analyzed experimentally: aluminum minichannel solar collector for low temperature applications, and copper minichannel solar collector for low to medium temperature applications.The aluminum minichannel solar collector has been tested for over a year alongside a conventional copper flat-plate solar collector of similar dimensions as t...

  15. 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.

  16. 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.

  17. 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...

  18. Study On the Performance of Solar Air Collectors with Cross V-Shaped Absorbing Plate and V-Shaped Bottom Plate%交叉V形吸热板V形底板空气集热器性能特性研究

    Institute of Scientific and Technical Information of China (English)

    闫崇强; 李明; 季旭; 罗熙

    2013-01-01

    以两种不同的交叉V形吸热板V形底板空气集热器(垂直型集热器:V形吸热板的方向与流道方向垂直,V形底板的方向与流道方向平行;平行型集热器:V形吸热板的方向与流道方向平行,V形底板的方向与流道方向垂直)为研究对象,对不同倾角、不同空气流速下两种空气集热器的性能进行了比较实验研究,同时对正向和反向通气时垂直型空气集热器的性能进行了测试分析.结果表明:垂直型空气集热器的性能优于平行型空气集热器,45°倾角时两台集热器的温升最高;垂直型和平行型空气集热器的最大效率分别为71%,68%;垂直型空气集热器反向流动时比正向流动时性能更好.%Two different types of solar air collectors with cross V-shaped absorbing plate and V-shaped bottom plate (for the vertical type collector,the direction of the V-shaped bottom plate is parallel to the flow direction while the direction of the V-shaped absorbing plate is perpendicular to it; for the parallel type collector,the direction of the V-shaped absorbing plate is parallel to the flow direction while the direction of the V-shaped bottom plate is perpendicular to it) are used as the research object in this paper,and their performances are studied and compared under different dip angle and different air flow velocity; meanwhile,the performance of the vertical type air collector is tested and analysed under forward and reverse entilation.The results show that the performance of the vertical type air collector is better than that of the parallel type air collector,and the rise of temperature of both collectors is the highest with an angle of 45°.The maximum efficiency of the vertical and the parallel type is 71% and 68%,respectively.With a reverse flow,the performance of the vertical type air collector is better than with a forward flow.

  19. A self-tractable solar collector

    Science.gov (United States)

    Abdulhadi, M.; Ghorayeb, F.

    2006-06-01

    An analytical experimental investigation into the thermal performance of a tubeless hemispherical (a spherical cap) solar collector for use in heating and cooling purposes is presented. The receiver plate surface temperature was estimated at the prevailing steady-state conditions from the energy balance equation on the absorber plate. From the experimental analytical investigation, the present collector was found to be much more efficient than a flat-plate collector. Fluid outlet temperatures over 95°C could be provided on mid clear shining sunny days. Remembering the easiness of building a complex of such a collector, it follows that plenty of residential and industrial implementations, mostly in heating and cooling refrigeration absorption cycles, could be undertaken.

  20. Aid To Solar Collector Development

    Science.gov (United States)

    1979-01-01

    Solar heating and cooling systems employ coatings to increase efficiency. Designers want a coating which absorbs solar heat to the maximum extent possible with minimal emittance of infrared radiation, which occurs when the collector plate gets hot. The coating is important because too much coating causes energy loss by emittance, too little reduces the collector's ability to absorb heat. NASA's Lewis Research Center, which conducts solar energy research, saw a need for a simple means of testing coating samples for emittance. Such equipment is available to research laboratories, but it is complex and expensive

  1. 平板式热管太阳能空气集热器热性能研究%Experimental Investigation on Thermal Performance of Flat Plate Heat Pipe Solar Air Collector

    Institute of Scientific and Technical Information of China (English)

    李世平; 向开根; 李雯; 罗会龙; 王霜

    2015-01-01

    Heat pipe has many advantages, such as higher heat transfer coefficient, lower transfer temperature-difference and a one-way heat transfer. A new flat plate heat pipe solar air collector was designed and built based on a reasonable construction. The test results indicated that the instantaneous efficiency of collector is 15.3%~74.5% under the climatic conditions of daily solar radiation being about 14.4 to19.8MJ/m2·day. Its daily average thermal efficiency is about 32.6%~53.5%with heat loss coefficient being 3.6~8.4W/(m2·K). The maximum outlet air temperature can reach 79.1℃. Compared with conventional air collectors, the new flat plate heat pipe solar air collector has higher thermal efficiency and outlet air.%热管具有传热系数高、传热温差小及单向传热等诸多优良特性。以热管为集热部件,试制了一种平板式热管太阳能空气集热器。测试结果表明,在日总太阳辐射为14.4MJ/m2~19.8MJ/m2的气候条件下,平板式热管太阳能空气集热器的瞬时集热效率在15.3%~74.5%之间,集热器出口空气温度可达79.1℃,其日平均集热效率约为32.6%~53.5%,其热损失系数约为3.6~8.4W/(m2·K)。与常规的太阳能空气集热器相比,平板式热管太阳能空气集热器具有较高的集热效率和较低的热损失系数,并且供热温度较高。

  2. 空气-水复合平板型太阳能集热器%Experiment test of hybrid air-water solar flat plate collector

    Institute of Scientific and Technical Information of China (English)

    赵东亮; 代彦军; 李勇

    2011-01-01

    This paper focuses on a new type of solar collector that has the potential for using in solar heating systems. It can use both air and water as the circulation mediums. Experiment results show that the collector efficiency is between 55%~65% when air is used as the circulation medium, while the efficiency is between 32%~34% for using water as the circulation medium, and it can meet the requirement of solar heating systems. Moreover, this collector is fairly cheap, therefore, especially suitable for the rural areas in north China.%提出了一种适用于太阳能供热采暖工程的新型太阳能空气-水复合平板集热器.该集热器可以单独使用空气、水或同时以空气和水作为集热工质.测试显示,该集热器空气循环集热效率为55%~65%,水循环集热效率为32%~34%,能够满足太阳能供热采暖工程的要求.该集热器成本不高,适用于在我国北方广大农村地区推广使用.

  3. 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.

  4. General solution of collector performance with axial conduction and end effects

    Science.gov (United States)

    Shouman, A. R.; Tag, I. A.

    The Phillips solution of the flat-plate solar collector is extended and utilized to examine the influence of the end losses on collector performance. The results of this study show that the influence of the end temperatures of the absorber plate is more significant than the losses due to the axial conductivity of an insulated end collector plate. It will be shown that for an insulated end collector, the loss in the heat removal factor due to axial conductivity is negligible in the region of interest for flat-plate collectors. However, the end temperatures of the collector plate have more significant influence on the same factor, showing losses in some regions and improvements in other regions. This study emphasizes the necessity of measuring the temperature of the absorber plate at both the fluid inlet and exit locations in order to determine accurately the collector performance parameters.

  5. Recommendations for European solar collector test methods (Liquid heating collectors)

    Science.gov (United States)

    Derrick, A.; Gillett, W. B.

    Standardized testing formats, equipment, conditions, and tests defined as part of the solar flat plate collector testing program performed by the Commission of the European Communities are detailed. The work is a product of efforts at 20 laboratories, and alternative methods have been characterized for tailoring tests to particular locations and climatic conditions. The testing methods are intended for collectors using a liquid as the heat transfer medium. Procedures have been defined for examining steady state and transient performance, heat loss, thermal capacity, pressure drop, and anemometry. Instrumentation types and accuracies have been defined, and a standardized format for presentation of results has been developed. The tests are tailored for determining the durability of the flat plate systems under simulated solar radiation conditions.

  6. Simple, economical solar collector

    Science.gov (United States)

    Anthony, K.

    1979-01-01

    Hot air solar collector designed for economy and simplicity is assembled from only three parts: (1) molded urethane foam body, (2) flat sheet metal collector panel and (3) transparent cover. Large arrays may be assembled by inserting male fittings of each collector into female fitting of adjacent collector.

  7. THEORETICAL STUDY OF SOLAR COLLECTOR WITH MINI PARABOLIC CONCENTRATOR

    Directory of Open Access Journals (Sweden)

    I TABET

    2013-12-01

    Full Text Available In this paper, numerical modeling and simulation of the thermal behavior of a solar collector vacuum tube with a concentration has been done, the value of adding a system of concentration at the back of the collector and try to increase the amount of solar radiation incident on the collector  in order to obtain high temperatures compared to traditional flat plate collector  and improved their energy performance, this type of collector  being integrated into buildings for domestic hot water, air conditioning and for cooling.

  8. Outdoor performance results for NBS Round Robin collector no. 1

    Science.gov (United States)

    Miller, D. R.

    1976-01-01

    The efficiency of a PPG flat-plate solar collector was evaluated utilizing an outdoor solar collector test facility at the NASA-Lewis Research Center, as part of the National Bureau of Standards 'round robin' collector test program. The correlation equation for collector thermal efficiency Eta curve fit of the data was: Eta = 0.666 - 1.003(Btu/hr-sq ft-F) Theta, where the parameter Theta is the difference between the average fluid temperature and the ambient temperature, all divided by the total flux impinging on the collector.

  9. Performance correlations of five solar collectors tested simultaneously outdoors

    Science.gov (United States)

    Miller, D. R.

    1976-01-01

    Collector thermal efficiency, and efficiency degradation with time were measured for 5 flat-plate solar collectors tested simultaneously in an outdoor solar collector test facility. Results indicate that by using collector performance parameters which account for diffuse insolation, outdoor data recorded on 'cloudy' days can be used as a measure of performance, as long as the ratio of direct to total insolation exceeds approximately 0.6. These outdoor results also show good agreement with thermal efficiency data obtained indoors in a solar simulator. Significant efficiency degradation occurred on only one of the five collectors exposed to outdoor conditions for a period of one to two years.

  10. A mobile apparatus for solar collector testing

    Science.gov (United States)

    Hotchkiss, G. B.; Simon, F. F.; Burmeister, L. C.

    1979-01-01

    The design, construction, and operation of a mobile apparatus for solar collector testing (MASCOT) is described. The MASCOT is a self-contained test unit costing about $10,000 whose only external requirement for operation is electrical power and which is capable of testing two water-cooled flat-plate solar collectors simultaneously. The MASCOT is small enough and light enough to be transported to any geographical site for outdoor tests at the location of collector usage. It has been used in both indoor solar simulator tests and outdoor tests.

  11. 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...... temperature, condensation) is investigated under different operating conditions (day and night). Under some conditions condensation might occur and heat gains could represent up to 55% of the total unglazed collector energy by night. Two TRNSYS collector models including condensation heat gains are also...... 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...

  12. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    ’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through......Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...

  13. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty......’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...

  14. Air/liquid collectors

    DEFF Research Database (Denmark)

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

    1997-01-01

    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...

  15. 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

  16. Air/liquid collectors

    DEFF Research Database (Denmark)

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

    1997-01-01

    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...... 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...

  17. Outdoor thermal efficiency evaluation of the Ying solar collector

    Science.gov (United States)

    1978-01-01

    The test procedure used and the test results obtained during an evaluation test program to obtain thermal efficiency performance data are presented. The flat plate collector used water/prestone antifreeze solution as the working fluid.

  18. Weathering of a liquid-filled solar collector

    Science.gov (United States)

    1979-01-01

    Report describes procedures and results of tests for effects of weathering on flat-plate liquid solar collector. Thermal performance was measured before and after natural weathering for 15-1/2 months by using Marshall Space Flight solar simulator.

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

    OpenAIRE

    Fan, Jianhua; Chen, Ziqian; Furbo, Simon; Perers, Bengt; Karlsson, Björn

    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 e...

  20. Performance test procedures for thermal collectors - Outdoor testing

    Science.gov (United States)

    Gillett, W. B.

    A review of outdoor solar collector test methods is presented, based largely on the CEC Recommendations for European Solar Collector Test Methods. Test facility design and instrumentation are discussed, with reference to their influence on measured collector efficiencies. Steady state outdoor testing, mixed indoor/outdoor testing and transient testing are reviewed, and it is concluded that although the testing of simple flat plate water heaters is fairly well understood, more work is now required to develop test methods for the new high performance collectors which are coming onto the market.

  1. Performance evaluation of a liquid solar collector

    Science.gov (United States)

    1979-01-01

    Report describes thermal performance and structural-load tests on commercial single glazed flat-plate solar collector with gross area of 63.5 sq ft that uses water as heat-transfer medium. Report documents test instrumentation and procedures and presents data as tables and graphs. Results are analyzed by standard data-reduction methods.

  2. Performance evaluation of an air solar collector

    Science.gov (United States)

    1979-01-01

    Indoor tests on signal-glazed flat-plate collector are described in report. Marhsall Space Flight Center solar simulator is used to make tests. Test included evaluations on thermal performance under various combinations of flow rate, incident flux, inlet temperature, and wind speed. Results are presented in graph/table form.

  3. Preliminary design package for Sunair SEC-601 solar collector

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    This report presents the preliminary design of the Owens-Illinois mode Sunair SEC-601 tubular air solar collector. Information in this package includes the Subsystem Design and Development Approaches, hazard analysis, and detailed drawings available as the Preliminary Design Review.

  4. NUMERICAL SIMULATION OF THE AIR FLOW AROUND THE ARRAYS OF SOLAR COLLECTORS

    Directory of Open Access Journals (Sweden)

    Vukman V Bakić

    2011-01-01

    Full Text Available This paper deals with the numerical simulation of air around the arrays of flat plate collectors and determination of the flow field, which should provide a basis for estimating a convective heat losses, a parameter which influences their working characteristics. Heat losses are the result of the reflection on the glass, conductive losses at the collector's absorber plate, radiation of the absorber plate and convective losses on the glass. Wind velocity in the vicinity of the absorber plate depends on its position in the arrays of collectors. Results obtained in the numerical simulation of flow around collectors were used as boundary conditions in modeling of thermal-hydraulic processes inside the solar collector. A method for coupling thermal-hydraulic processes inside the collector with heat transfer from plate to tube bundle was developed, in order to find out the distribution of the temperature of the absorber plate and the efficiency of the flat plate collectors. Analyses of flow around arrays of collectors are preformed with RNG k - ε model. Three values for free-stream velocity were analysed, i.e. 1 m/s, 5 m/s and 10 m/s, as well as two values for the angle between the ground and the collector (20° and 40°. Heat transfer coefficient was determined from the theory of boundary layer. Heat transfer inside the plate cavity was analyzed assuming constant intensity of radiation.

  5. Virtual Quantum Subsystems

    OpenAIRE

    Zanardi, Paolo

    2001-01-01

    The physical resources available to access and manipulate the degrees of freedom of a quantum system define the set $\\cal A$ of operationally relevant observables. The algebraic structure of $\\cal A$ selects a preferred tensor product structure i.e., a partition into subsystems. The notion of compoundness for quantum system is accordingly relativized. Universal control over virtual subsystems can be achieved by using quantum noncommutative holonomies

  6. Virtual quantum subsystems.

    Science.gov (United States)

    Zanardi, P

    2001-08-13

    The physical resources available to access and manipulate the degrees of freedom of a quantum system define the set A of operationally relevant observables. The algebraic structure of A selects a preferred tensor product structure, i.e., a partition into subsystems. The notion of compoundness for quantum systems is accordingly relativized. Universal control over virtual subsystems can be achieved by using quantum noncommutative holonomies

  7. 平板式太阳能空气集热器流道改进的试验研究和数值模拟%Experimental investigation and numerical simulation on improvement of flat-plate solar air collector flow channels

    Institute of Scientific and Technical Information of China (English)

    丁刚; 左然; 张旭鹏; 王坤

    2011-01-01

    对传统平板式太阳能空气集热器的流道进行了改进,把对角型进出口流道改为多进出口式流道.对改进的集热器的性能进行了试验测试.新的进出口流道消除了吸热板和空气换热不均的现象,出口温度提升明显.在相同条件下,集热器的瞬时效率增加约20%.用CFD方法对集热器内部的流场结构和传热进行的数值模拟对比表明,传统集热器内部存在流动死区,中心截面温度分布不均匀,吸热板上有局部的高温区域,改进后的集热器流场和温度场分布得较均匀.%The flow channels of traditional flat-plate solar air collector were changed from diagonal inlet/outlet to multi-inlet/outlet. Experimental investigation on characteristics of solar air collectors after the improvement of flow channels was reported. The inlet and outlet channels of the conventional air collector were improved. The new flow channel eliminates the ununiformity of heat transfer between air and absorber plate, so there is a distinct temperature increasing at the outlet. The instantaneous efficiency is improved by about 20% at the same condition. An analysis of flow characteristics and heat transfer in the collectors had been carried out by using Computation Fluid Dynamic (CFD). There is the dead zone in flow field of traditional collector. The temperature distribution of center section is different and there is local high-temperature region on the heat-absorbing plate in the traditional collector, while the flow field and temperature distribution are uniform in the improved collector.

  8. EVALUATION OF EVACUATED TUBULAR SOLAR COLLECTORS FOR LARGE SDHW SYSTEMS AND COMBINED SPACE HEATING SYSTEMS

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    . Based on thesemodels, the thermal performance of large solar domestic hot water (DHW) systems and combined domestichot water and space heating systems with the four evacuated tubular collectors was determined. To make acomparison with traditional flat-plate collectors, similar simulations were also...... carried out for systems with atypical flat-plate collector. The results show that the thermal advantage of evacuated tubular collectors variesgreatly from system to system, and increases with the solar fraction. Furthermore, the higher the operationtemperature of the collector in the system is......In the present study, detailed investigations on evacuated tubular solar collectors for large solarheating systems have been carried out. Four types of evacuated tubular solar collectors were used in theinvestigation. Based on laboratory tests, simulation models for the collectors were determined...

  9. 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

    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...... 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...

  10. 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

  11. Investigation on Installation height of Storage Tank for Natural Circulation Flat Plate Solar Collector%自然循环平板式太阳能热水器水箱放置高度的研究

    Institute of Scientific and Technical Information of China (English)

    郑土逢; 李明; 魏生贤; 罗熙; 王炳灿

    2011-01-01

    The device of natural circulation flat plate solar water heater has been built.In accordance with the national testing standard methods, the efficiency of the system was tested.The transient model of NFSWH has been developed by using the TRNSYS simulation program.The effect of installation height between the bottom of the tank and the outlet of the collector on efficiency of the solar collector has been investigated both theoretically and experimentally.The data show the theoretical results are highly consistent with the experimental ones.Results indicate that the optimum value of installation height is 0.74m with the maximum efficiency of 67.5% for the system with a total area of 1.5m2 and a storage water tank capacity of 120L.When the installation height is between 0.44 and 1.04 m, the change of thermal efficiency of the solar system is at a range of 3%.%搭建了自然循环平板式太阳能热水器(NFSWH)的实验平台,根据太阳能热水器国家测试标准方法对系统的热效率进行测试.用TRNSYS软件建立了NFSWH的瞬态模型.模拟和实际测量了水箱放置高度对热水器热效率的影响.结果显示,实验与模拟吻合较好.对于集热面积为1.5m2水箱容积为120L的系统,水箱底到集热器出口的高度(Hr)为0.74m时,系统的热效率最大(67.7%).放置高度为0.44-1.04m时,系统集热效率变化不大,在3%以内.

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

    OpenAIRE

    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...

  13. Numerical Investigation of Nanofluid-based Solar Collectors

    Science.gov (United States)

    Karami, M.; Raisee, M.; Delfani, S.

    2014-08-01

    Solar thermal collectors are applicable in the water heating or space conditioning systems. Due to the low efficiency of the conventional collectors, some suggestions have been presented for improvement in the collector efficiency. Adding nanoparticles to the working fluid in direct absorption solar collector, which has been recently proposed, leads to improvement in the working fluid thermal and optical properties such as thermal conductivity and absorption coefficient. This results certainly in collector efficiency enhancement. In this paper, the radiative transfer and energy equations are numerically solved. Due to laminar and fully developed flow in the collector, the velocity profile is assumed to be parabolic. As can be observed from the results, outlet temperature of collector is lower than that obtained using uniform velocity profile. Furthermore, a suspension of carbon nanohorns in the water is used as the working fluid in the model and its effect on the collector efficiency is investigated. It was found that the presence of carbon nanohorns increases the collector efficiency by about 17% compared to a conventional flat-plate collector. In comparison with the mixture of water and aluminium nanoparticles, a quite similar efficiency is obtained using very lower concentration of carbon nanohorns in the water.

  14. A Process Heat Application Using Parabolic Trough Collector

    Science.gov (United States)

    Yılmaz, İbrahim Halil; Söylemez, Mehmet Sait; Hayta, Hakan; Yumrutaş, Recep

    A pilot study has been performed based on a heat process application that is designed, installed and tested at Gaziantep University to establish the technical and economic feasibility of high temperature solar-assisted cooking process. The system has been designed to be satisfying the process conditions integrated with parabolic trough solar collector (PTSC). It is primarily consists of the PTSC array, auxiliary heater, plate type heat exchanger, cooking system and water heating tanks. In the operation of the process heat application, the energy required to cook wheat (used as cooking material) has been supplied from solar energy which is transferred to heat transfer fluid (HTF) by heat exchanging units and finally discharged to water in order to produce bulgur. The performance parameters of the sub-systems and the process compatibility have been accomplished depending on the system operation. In addition that the system performance of the high temperature solar heat process has been presented and the recommendations on its improvement have been evaluated by performing an experimental study. As a result that the use of solar energy in process heat application has been projected and its contribution to economics view with respect to conventional cooking systems has been conducted.

  15. The JPL parabolic dish project. [solar collectors technology development

    Science.gov (United States)

    Truscello, V. C.; Williams, A. N.

    1980-01-01

    The parabolic dish solar collector is a highly versatile concentrating collector system that can produce heat for many thermal processes and electricity by coupling the collector to a suitable heat engine. This paper discusses a project for the development of these collector systems and summarizes contracts with industry for developing the dish subsystems which include concentrator, receiver, and heat engine. An early market for dishes is the dispersed small community market which depends heavily on oil to operate diesel or steam turbine plants in order to generate electricity. The present contracts with industry for conducting engineering experiments using the developed dish hardware to demonstrate the technology in these early opportunity markets is also discussed.

  16. 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.

  17. Yearly average performance of the principal solar collector types

    Energy Technology Data Exchange (ETDEWEB)

    Rabl, A.

    1981-01-01

    The results of hour-by-hour simulations for 26 meteorological stations are used to derive universal correlations for the yearly total energy that can be delivered by the principal solar collector types: flat plate, evacuated tubes, CPC, single- and dual-axis tracking collectors, and central receiver. The correlations are first- and second-order polynomials in yearly average insolation, latitude, and threshold (= heat loss/optical efficiency). With these correlations, the yearly collectible energy can be found by multiplying the coordinates of a single graph by the collector parameters, which reproduces the results of hour-by-hour simulations with an accuracy (rms error) of 2% for flat plates and 2% to 4% for concentrators. This method can be applied to collectors that operate year-around in such a way that no collected energy is discarded, including photovoltaic systems, solar-augmented industrial process heat systems, and solar thermal power systems. The method is also recommended for rating collectors of different type or manufacturer by yearly average performance, evaluating the effects of collector degradation, the benefits of collector cleaning, and the gains from collector improvements (due to enhanced optical efficiency or decreased heat loss per absorber surface). For most of these applications, the method is accurate enough to replace a system simulation.

  18. Comparison of Electrical and Thermal Performances of Glazed and Unglazed PVT Collectors

    Directory of Open Access Journals (Sweden)

    Jin-Hee Kim

    2012-01-01

    Full Text Available Photovoltaic-thermal (PVT collectors combine photovoltaic modules and solar thermal collectors, forming a single device that receives solar radiation and produces electricity and heat simultaneously. PVT collectors can produce more energy per unit surface area than side-by-side PV modules and solar thermal collectors. There are two types of liquid-type flat-plate PVT collectors, depending on the existence of glass cover over PV module: glass-covered (glazed PVT collectors, which produce relatively more thermal energy but have lower electrical yield, and uncovered (unglazed PVT collectors, which have relatively lower thermal energy with somewhat higher electrical performance. In this paper, the experimental performance of two types of liquid-type PVT collectors, glazed and unglazed, was analyzed. The electrical and thermal performances of the PVT collectors were measured in outdoor conditions, and the results were compared. The results show that the thermal efficiency of the glazed PVT collector is higher than that of the unglazed PVT collector, but the unglazed collector had higher electrical efficiency than the glazed collector. The overall energy performance of the collectors was compared by combining the values of the average thermal and electrical efficiency.

  19. Step tracking program for concentrator solar collectors

    Science.gov (United States)

    Ciobanu, D.; Jaliu, C.

    2016-08-01

    The increasing living standards in developed countries lead to increased energy consumption. The fossil fuel consumption and greenhouse gas effect that accompany the energy production can be reduced by using renewable energy. For instance, the solar thermal systems can be used in temperate climates to provide heating during the transient period or cooling during the warmer months. Most used solar thermal systems contain flat plate solar collectors. In order to provide the necessary energy for the house cooling system, the cooling machine uses a working fluid with a high temperature, which can be supplied by dish concentrator collectors. These collectors are continuously rotated towards sun by biaxial tracking systems, process that increases the consumed power. An algorithm for a step tracking program to be used in the orientation of parabolic dish concentrator collectors is proposed in the paper to reduce the consumed power due to actuation. The algorithm is exemplified on a case study: a dish concentrator collector to be implemented in Brasov, Romania, a location with the turbidity factor TR equal to 3. The size of the system is imposed by the environment, the diameter of the dish reflector being of 3 meters. By applying the proposed algorithm, 60 sub-programs are obtained for the step orientation of the parabolic dish collector over the year. Based on the results of the numerical simulations for the step orientation, the efficiency of the direct solar radiation capture on the receptor is up to 99%, while the energy consumption is reduced by almost 80% compared to the continuous actuation of the concentrator solar collector.

  20. Thermal performance evaluation of the Semco (liquid) solar collector

    Science.gov (United States)

    1979-01-01

    Procedures used and results obtained during the evaluation test program on a flat plate collector which uses water as the working fluid are discussed. The absorber plate is copper tube soldered to copper fin coated with flat black paint. The glazing consists of two plates of Lo-Iron glass; the insulation is polyurethane foam. The collector weight is 242.5 pounds with overall external dimensions of approximately 48.8 in. x 120.8 in. x 4.1 in. The test program was conducted to obtain thermal performance data before and after 34 days of weather exposure test.

  1. Hybrid thermoelectric solar collector design and analysis

    Science.gov (United States)

    Roberts, A. S., Jr.; Shaheen, K. E.

    1982-01-01

    A flat-plate solar collector is conceived where energy cascades through thermoelectric power modules generating direct-current electricity. The intent of this work was to choose a collector configuration and to perform a steady-state thermal performance assessment. A set of energy balance equations were written and solved numerically for the purpose of optimizing collector thermal and electrical performance. The collector design involves finned columns of thermoelectric modules imbedded in the absorber plate (hot junction) over a parallel array of vertical tubes. The thermoelectric power output is limited by the small hot-junction/cold-junction temperature difference which can be maintained under steady-state conditions. The electric power per unit tube pass area is found to have a maximum as a function of a geometric parameter, while electric power is maximized with respect to an electric resistance ratio. Although the electric power efficiency is small, results indicate that there is sufficient electric power production to drive a coolant circulator, suggesting the potential for a stand-alone system.

  2. Hybrid thermoelectric solar collector design and analysis

    Science.gov (United States)

    Roberts, A. S., Jr.; Shaheen, K. E.

    1982-01-01

    A flat-plate solar collector is conceived where energy cascades through thermoelectric power modules generating direct-current electricity. The intent of this work was to choose a collector configuration and to perform a steady-state thermal performance assessment. A set of energy balance equations were written and solved numerically for the purpose of optimizing collector thermal and electrical performance. The collector design involves finned columns of thermoelectric modules imbedded in the absorber plate (hot junction) over a parallel array of vertical tubes. The thermoelectric power output is limited by the small hot-junction/cold-junction temperature difference which can be maintained under steady-state conditions. The electric power per unit tube pass area is found to have a maximum as a function of a geometric parameter, while electric power is maximized with respect to an electric resistance ratio. Although the electric power efficiency is small, results indicate that there is sufficient electric power production to drive a coolant circulator, suggesting the potential for a stand-alone system.

  3. Pressure Garment Subsystem Roadmap

    Science.gov (United States)

    Ross, Amy J.

    2010-01-01

    The Constellation program pressure garment subsystem (PGS) team has created a technical roadmap that communicates major technical questions and how and when the questions are being answered in support of major project milestones. The roadmap is a living document that guides the team priorities. The roadmap also communicates technical reactions to changes in project priorities and funding. This paper presents the roadmap and discusses specific roadmap elements in detail as representative examples to provide insight into the meaning and use of the roadmap.

  4. 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.

  5. Horizontally mounted solar collector

    Science.gov (United States)

    Black, D. H. (Inventor)

    1979-01-01

    Solar energy is collected by using a vertical deflector assembly, a stationary reflector and a horizontally mounted solar collector. The deflector assembly contains a plurality of vanes which change the direction of the solar energy to the vertical, while constantly keeping the same side of the deflector facing the sun. The vertical rays are then reflected off the stationary reflector and are then absorbed by the collector.

  6. 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

  7. 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.

  8. Thermal performance of integration of solar collectors and building envelopes

    Institute of Scientific and Technical Information of China (English)

    于国清; 龚小辉; 曹双华

    2009-01-01

    The integration of building with solar collector was studied. The theoretical model of integration of building envelopes and flat plate solar collectors was set up and the thermal performance of integration was studied in winter and summer,and compared to envelopes without solar collectors. The results show that the solar collection efficiency is raised in the integration of building envelopes and solar collectors with the air layer doors closed. This is true whether in winter or summer. The increment is higher as the inlet water temperature increases or the ambient temperature is low. In winter,the heat loss is significantly reduced through integration of the building envelopes and solar collectors with the closed air layer doors. The integration with the open air layer door is worse than that without collectors. In summer,the heat gains of the integration of envelopes and solar collectors are more obviously reduced than envelopes without collectors,the integration with the open air layer door is a little better than the closed one,but the difference is very small.

  9. Environmental Control Subsystem Development

    Science.gov (United States)

    Laidlaw, Jacob; Zelik, Jonathan

    2017-01-01

    Kennedy Space Center's Launch Pad 39B, part of Launch Complex 39, is currently undergoing construction to prepare it for NASA's Space Launch System missions. The Environmental Control Subsystem, which provides the vehicle with an air or nitrogen gas environment, required development of its local and remote display screens. The remote displays, developed by NASA contractors and previous interns, were developed without complete functionality; the remote displays were revised, adding functionality to over 90 displays. For the local displays, multiple test procedures were developed to assess the functionality of the screens, as well as verify requirements. One local display screen was also developed.

  10. HETE Satellite Power Subsystem

    OpenAIRE

    1993-01-01

    The HETE (High-Energy Transient Experiment) satellite a joint project between MIT's Center for Space Research and AeroAstro. is a high-energy gamma-ray burst/X-Ray/UV observatory platform. HETE will be launched into a 550 km circular orbit with an inclination of 37.7°, and has a design lifetime of 18 months. This paper presents a description of the spacecraft's power subsystem, which collects, regulates, and distributes power to the experiment payload modules and to the various spacecraft sub...

  11. Debris measure subsystem of the nanosatellite IRECIN

    Science.gov (United States)

    Ferrante, M.; di Ciolo, L.; Ortenzi, A.; Petrozzi, M.; del Re, V.

    2003-09-01

    The on board resources, needed to perform the mission tasks, are very limited in nano-satellites. This paper proposes an Electronic real-time system that acquires space debris measures. It uses a piezo-electric sensor. The described device is a subsystem on board of the IRECIN nanosatellite composed mainly by a r.i.s.c. microprocessor, an electronic part that interfaces to the debris sensor in order to provide a low noise electrical and suitable range to ADC 12 bit converter, and finally a memory in order to store the data. The microprocessor handles the Debris Measure System measuring the impacts number, their intensity and storing their waves form. This subsystem is able to communicate with the other IRECIN subsystems through I2C Bus and principally with the "Main Microprocessor" subsystem allowing the data download directly to the Ground Station. Moreover this subsystem lets free the "Main Microprocessor Board" from the management and charge of debris data. All electronic components are SMD technology in order to reduce weight and size. The realized Electronic board are completely developed, realized and tested at the Vitrociset S.P.A. under control of Research and Development Group. The proposed system is implemented on the IRECIN, a modular nanosatellite weighting less than 1.5 kg, constituted by sixteen external sides with surface-mounted solar cells and three internal Al plates, kept together by four steel bars. Lithium-ions batteries are added for eclipse operations. Attitude is determined by two three-axis magnetometers and the solar panels data. Control is provided by an active magnetic control system. The spacecraft will be spin-stabilized with the spin-axis normal to the orbit. debris and micrometeoroids mass and velocity.

  12. Long-term weathering effects on the thermal performance of the Lennox/Honeywell (liquid) solar collector

    Science.gov (United States)

    1978-01-01

    The test procedures used and the results obtained during the evaluation test program of the Lennox/Honeywell double covered liquid solar collector. The tests were performed under simulated conditions, following long-term exposure to natural weathering conditions. The Lennox/Honeywell collector is a flat-plate solar collector. The absorber plate is steel with copper tubes bonded on the upper surface, and is coated with black chrome. Visual inspection of the collector indicated slight discoloration of the absorber plate. Results indicate that performance degradation had occurred. Absorptivity and/or transmissivity decreased as a result of the weathering.

  13. Experimental studies of a matrix-tubular solar air collector

    Energy Technology Data Exchange (ETDEWEB)

    Plesca, M.; Varlan, P. [Moldova Technical Univ., Chisinau (Moldova, Republic of). Dept. of Heat and Gas Supply and Ventilation

    2009-06-15

    The most common types of solar air collectors (SAC) are contact-type and matrix-type collectors, with the latter being more efficient. This paper described the design and testing of a matrix-tubular flat solar air collector in the city of Chisinau, Moldova, where the outdoor climatic radiation, heat, and humidity characteristics are favorable for the efficient use of solar energy for building heating and drying applications. The amount of solar energy absorbed by a solar energy air collector depends on the level of insulation and orientation of the solar collector; the absorbance of the absorber surface; and the transmittance of the cover material. This study examined the heat transfer, efficiency, and pressure drop using copper tubes inserted perpendicular to the plane of the absorber plate. The SAC consists of a glazed insulated case, an absorber, and ducting for cold air delivery and hot air discharge. Copper tubes are inserted perpendicular to the plane of the absorber. The absorber is installed in the body of the SAC in such a way that it divides it into an upper channel and lower channel. The channel bottom is lined with aluminium foil that reflects solar radiation coming through the tubes and decreases heat loss in the solar collector. Copper tubes increase the heat exchange surface, create air turbulence and intensify heat transfer. This increases the efficiency of the solar collector. The pressure drop of the matrix-tubular solar air collector is 40 per cent lower than that of the matrix-plate collectors. 11 refs., 2 tabs., 6 figs.

  14. 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.

  15. Miniature, ruggedized data collector

    Science.gov (United States)

    Jackson, Scott; Calcutt, Wade; Knobler, Ron; Jones, Barry; Klug, Robert

    2009-05-01

    McQ has developed a miniaturized, programmable, ruggedized data collector intended for use in weapon testing or data collection exercises that impose severe stresses on devices under test. The recorder is designed to survive these stresses which include acceleration and shock levels up to 100,000 G. The collector acquires and stores up to four channels of signal data to nonvolatile memory for later retrieval by a user. It is small (< 7 in3), light weight (< 1 lb), and can operate from various battery chemistries. A built-in menuing system, accessible via a USB interface, allows the user to configure parameters of the recorder operation, such as channel gain, filtering, and signal offsets, and also to retrieve recorded data for analysis. An overview of the collector, its features, performance, and potential uses, is presented.

  16. Thermal performance evaluation of Solar Energy Products Company (SEPCO) 'Soloron' collector tested outdoors

    Science.gov (United States)

    Chiou, J., Sr.

    1977-01-01

    The test article, Model EF-212, Serial Nr. 002, is a single glazed collector with a nonselective absorber plate, using flowing air as the heat transfer medium. The absorber plate and box frame are aluminum and the insulation is one inch isocyanurate foam board with thermal conductivity of 0.11 (BTU/sq ft Hr0/ft.) The tests included the following. (1) time constant test, (2) collector efficiency test, (3) collector stagnation test, (4) incident angle modifier test, (5) load test, (6) weathering test, and (7) absorber plate optical properties test. The results of these tests are tabulated, graphed, or otherwise recorded.

  17. Indoor test for thermal performance evaluation of Sunworks (liquid) solar collector

    Science.gov (United States)

    Shih, K.

    1977-01-01

    Test procedures used and test results obtained from an evaluation test program conducted on a single covered liquid solar collector under simulated conditions are presented. The test article was a flat plate solar collector using water as the heat transfer medium. The absorber plate was copper with copper tubes bonded by soft solder. The plate was coated with Enthone selective black with an absorptivity factor of .87 approximately .92 and an emissivity factor of .10 approximately .20. A time constant test and incident angle modifier test were conducted to determine the transient effect and the incident angle effect on the collector.

  18. Characterization of a direct methanol fuel cell using Hilbert curve fractal current collectors

    Energy Technology Data Exchange (ETDEWEB)

    Kuan, Yean-Der [Department of Refrigeration, Air-Conditioning and Energy Engineering, National Chun-Yi University of Technology, NO 35, Lane 215, Section 1, Chung-Shan Road, Taiping City, 411 Taichung County (China); Chang, Jing-Yi [Department of Mechanical and Electro-Mechanical Engineering, Tamkang University, Tamsui, 251 Taipei County (China); Lee, Shi-Min [Department of Aerospace Engineering, Tamkang University, Tamsui, 251 Taipei County (China); Lee, Shah-Rong [Department of Mechanical Engineering, Technology and Science Institute of Northern Taiwan, Peitou, 112 Taipei (China)

    2009-02-01

    The current collector or bi-polar plate is a key component in direct methanol fuel cells (DMFCs). Current collector geometric designs have significant influence on cell performance. This paper presents a continuous type fractal geometry using the Hilbert curve applied to current collector design in a direct methanol fuel cell. The Hilbert curve fractal geometry current collector is named HFCC (Hilbert curve fractal current collector). This research designs the current collector using a first, second and third order open carved HFCC shape. The cell performances of the different current collector geometries were measured and compared. Two important factors, the free open ratio and total perimeter length of the open carved design are discussed. The results show that both the larger free open ratio and longer carved open perimeter length present higher performance. (author)

  19. Characterization of a direct methanol fuel cell using Hilbert curve fractal current collectors

    Science.gov (United States)

    Kuan, Yean-Der; Chang, Jing-Yi; Lee, Shi-Min; Lee, Shah-Rong

    The current collector or bi-polar plate is a key component in direct methanol fuel cells (DMFCs). Current collector geometric designs have significant influence on cell performance. This paper presents a continuous type fractal geometry using the Hilbert curve applied to current collector design in a direct methanol fuel cell. The Hilbert curve fractal geometry current collector is named HFCC (Hilbert curve fractal current collector). This research designs the current collector using a first, second and third order open carved HFCC shape. The cell performances of the different current collector geometries were measured and compared. Two important factors, the free open ratio and total perimeter length of the open carved design are discussed. The results show that both the larger free open ratio and longer carved open perimeter length present higher performance.

  20. Regional transmission subsystem planning

    Energy Technology Data Exchange (ETDEWEB)

    Costa Bortoni, Edson da [Quadrante Softwares Especializados Ltda., Itajuba, MG (Brazil); Bajay, Sergio Valdir; Barros Correia, Paulo de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Santos, Afonso Henriques Moreira; Haddad, Jamil [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    This work presents an approach for the planning of transmission systems by employing mixed--integer linear programming to obtain a cost and operating characteristics optimized system. The voltage loop equations are written in a modified form, so that, at the end of the analysis, the model behaves as a DC power flow, with the help of the two Kirchhoff`s laws, exempting the need of interaction with an external power flow program for analysis of the line loading. The model considers the occurrence of contingencies, so that the final result is a network robust to the most severe contingencies. This whole technique is adapted to the regional electric power transmission subsystems. (author) 9 refs., 4 figs.

  1. Operationally Responsive Spacecraft Subsystem Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Saber Astronautics proposes spacecraft subsystem control software which can autonomously reconfigure avionics for best performance during various mission conditions....

  2. Black Liquid Solar Collector Demonstrator.

    Science.gov (United States)

    Weichman, F. L.; Austen, D. J.

    1979-01-01

    Describes the details of constructing, and use of, a solar collector. Uses a black liquid to absorb the energy, the thermosyphon effect to drive the liquid through the collector, and a floodlamp as a surrogate sun. (GA)

  3. Studies efficiency solar air collector

    OpenAIRE

    YORKIN SODIKOVICH ABBASOV; MIRSOLI ODILJANOVICH UZBEKOV

    2016-01-01

    The article presents an analysis of the existing solar air collectors. A description of the design and the results of experimental studies on the effectiveness of the solar air collector with an absorber of from metal shavings.

  4. The Olympic Collectors

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Products bearing Beijing Olympics images are big business for China’s dedicated collectors As every December over last few years,retired teacher Li Mi in Beijing started to collect thick stacks of postcards sent by her former students from her mailbox in the weeks running up to the New Year.

  5. Leaves: Nature's Solar Collectors

    Science.gov (United States)

    Isabelle, Aaron D.; de Groot, Cornelis

    2009-01-01

    One of the most captivating things about plants is the way they capture the Sun's energy, but this can be a difficult topic to cover with elementary students. Therefore, to help students to make a concrete connection to this abstract concept, this series of solar-energy lessons focuses on leaves and how they act as "solar collectors." As students…

  6. Standard Test Method for Determining Thermal Performance of Tracking Concentrating Solar Collectors

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1987-01-01

    1.1 This test method covers the determination of thermal performance of tracking concentrating solar collectors that heat fluids for use in thermal systems. 1.2 This test method applies to one- or two-axis tracking reflecting concentrating collectors in which the fluid enters the collector through a single inlet and leaves the collector through a single outlet, and to those collectors where a single inlet and outlet can be effectively provided, such as into parallel inlets and outlets of multiple collector modules. 1.3 This test method is intended for those collectors whose design is such that the effects of diffuse irradiance on performance is negligible and whose performance can be characterized in terms of direct irradiance. Note 1—For purposes of clarification, this method shall apply to collectors with a geometric concentration ratio of seven or greater. 1.4 The collector may be tested either as a thermal collection subsystem where the effects of tracking errors have been essentially removed from t...

  7. 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....... The method is applied for horizons of up to 42 hours. Solar heating systems naturally come with a hot water tank, which can be utilized for energy storage also for other energy sources. Thereby such systems can become an important part of energy systems with a large share of uncontrollable energy sources......, such as wind power. In such a scenario online forecasting is a vital tool for optimal control and utilization of solar heating systems. The method is a two-step scheme, where first a non-linear model is applied to transform the solar power into a stationary process, which then is forecasted with robust time...

  8. 一种新型双效太阳能平板集热器的光热性能研究%STUDY OF THERMAL PERFORMANCE OF A NOVEL DUAL-FUNCTION FLAT PLATE SOLAR COLLECTOR

    Institute of Scientific and Technical Information of China (English)

    季杰; 马进伟; 孙炜; 张杨; 范雯; 何伟; 张爱凤

    2011-01-01

    A novel flat-plane solar collector with L-shaped fins was proposed in this paper, which worked as air heater or water heater according to the season and applications. Experimental investigation was carried out to study the performance of the collector under different operating conditions. The experimental results indicate that the thermal efficiency reaches 40% as air heater that is higher than conventional flat plane air heater, the thermal efficiency of the collector is 49.7% as water heater. Therefore the novel collector can be applied as both air heater and water heater with high efficiency.%提出一种新型太阳能平板集热器,可实现加热空气与加热水两种工作模式,并设计了一种新型的“L”型翅片结构将两种功能有效结合.对这种新型集热器的不同工况分别进行了实验测试,得到两种工作状态下的太阳能光热转换效率.实验表明,空气集热日平均光热转换效率可达到40%以上,高于传统的空气集热器;水集热的效率达到49.7%.两种集热功能均能以高效率实现.

  9. 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.

  10. Use of membrane collectors in electrostatic precipitators.

    Science.gov (United States)

    Bayless, D J; Pasic, H; Alam, M K; Shi, L; Haynes, B; Cochran, J; Khan, W

    2001-10-01

    Membrane collection surfaces, developed and patented by researchers at Ohio University, were used to replace steel plates in a dry electrostatic precipitator (ESP). Such replacement facilitates tension-based rapping, which shears the adhered particle layer from the collector surface more effectively than hammer-based rapping. Tests were performed to measure the collection efficiency of the membranes and to quantify the potential improvements of this novel cleaning technique with respect to re-entrainment. Results indicate that even semiconductor materials (e.g., carbon fibers) collect ash nearly as efficiently as steel plates, potentially indicating that collection surface resistivity is primarily dictated by the accumulated ash layer and not by the underlying plate conductivity. In addition, virtually all sheared particles separated from the collecting membranes fell within the boundary layer of the membrane, indicating extremely low potential for re-entrainment.

  11. Thermal performance evaluation of the Calmac (liquid) solar collector

    Science.gov (United States)

    Usher, H.

    1978-01-01

    The procedures used and the results obtained during the evaluation test program on the S. N. 1, (liquid) solar collector are presented. The flat plate collector uses water as the working fluid. The absorber plate is aluminum with plastic tubes coated with urethane black. The glazing consists of .040 in fiberglass reinforced polyester. The collector weight is 78.5 pounds with overall external dimensions of approximately 50.3in. x 98.3in. x 3.8in. The following information is given: thermal performance data under simulated conditions, structural behavior under static loading, and the effects of long term exposure to natural weathering. These tests were conducted using the MSFC Solar Simulator.

  12. 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)

  13. Thermal performance evaluation of the Solargenics solar collector at outdoor conditions

    Science.gov (United States)

    1978-01-01

    Test procedures used during the performance of an evaluation program are presented. The test program was conducted to obtain the following performance data and information on the solar collector. (1) thermal performance data under outdoor conditions; (2) structural behavior of collector under static conditions; (3) effects of long term exposure to material weathering elements. The solargenics is a liquid, single-glazed, flat plate collector. Approximate dimensions of each collector are 240 inches long, 36 inches wide, and 3.5 inches in depth.

  14. Testing of a solar collector with concentrating mirrors

    Science.gov (United States)

    1980-01-01

    Commerical flat-plate solar collector with concentrating mirrors has been tested for thermal performance, structured behavior under static load, and effects of long-term natural weathering. Report documents results of testing and concludes that absorptivity was degraded by weathering.

  15. A solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, L.L.; Avakyan, Yu V.; Dabagyan, T.N.; Grakovich, L.P.; Khustalev, D.K.; Morgun, V.A.; Vartanyan, A.V.

    1984-01-01

    During collector operation, solar emission is absorbed by the evaporator section of the heating tube; the degree of blackness of the forward wall of the section is increased significantly by the use of corrugations in this section. Boiling of the working fluid in the longitudinal slotted channels is accompanied by outbursts of the steam fluid mixture in the direction of the forward wall, resulting in wetting of the longitudinal corrugation on this wall. In this solar collector, there is a continuous flow of the working fluid onto the internal surface of the leading wall of the evaporation section of the heat tube; the working fluid evaporation process is accelerated by the spraying resulting from the popping of vapor bubbles.

  16. Solar collector array

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Experimental and Theoretical Study for Performance Enhancement of Air Solar Collectors by Using Different Absorbers

    Directory of Open Access Journals (Sweden)

    Ahmed A. Mohammad Saleh

    2016-09-01

    Full Text Available An experimental and theoretical study has been done to investigate the thermal performance of different types of air solar collectors, In this work air solar collector with a dimensions of (120 cm x90 cm x12 cm , was tested under climate condition of Baghdad city with a (43° tilt angel by using the absorber plate (1.45 mm thickness, 115 cm height x 84 cm width, which was manufactured from iron painted with a black matt. The experimental test deals with five types of absorber:- Conventional smooth flat plate absorber , Finned absorber , Corrugated absorber plate, Iron wire mesh on absorber And matrix of porous media on absorber . The hourly and average efficiency of the collectors were investigated for three values of mass flow rates (0.016 kg/s to 0.027 kg/s for each type of collector and then the porosity for the last collector type was tested by changing the porosity of porous media. A typical air solar collector has been studied Theoretically to build a standard software for testing any type of air solar collectors with local weather data . From the experimental study it can be seen by using some obstacle material to the air flow (fins, corrugated absorber plate, iron wire mesh porous media on the absorber could be enhanced the efficiencies not less than 4 % for finned type and 8 % for corrugated and 25 % for mesh and 30 % for porous media comparing with flat plate (smooth collector . Theoretically, the results showed that the collector with high convention heat transfer coefficient porous media has high hourly efficiency about (η = 56 % and iron wire mesh on absorber ( η = 52 % , on the other side the minimum performance occurred in the flat plate absorber (η = 28 %. Comparison of results reveals that the theoretical predictions agree reasonably well with experimental results. And the difference between the theoretical and experimental efficiency in general was between (1─ 15 %.

  18. 平板太阳能集热器与建筑物屋顶的一体化结构设计%Integrated Structural Design of Flat-plate Solar Collector and Building Roof

    Institute of Scientific and Technical Information of China (English)

    梁春华; 吴永明; 曾玲

    2015-01-01

    在建筑设计阶段考虑太阳能集热器与建筑物屋顶的一体化结构设计,可以满足太阳能利用、设施维护、屋顶空间利用和建筑美学等要求。在计算出接收太阳辐射的最佳屋顶坡度的基础上,对双坡对称屋顶、双坡不对称屋顶、单坡屋顶和平屋顶等几种屋顶结构形式进行太阳能集热器安装结构的设计比较,分别分析在不同纬度地区每种屋顶结构在可利用的屋面面积、有效集热器面积和屋顶空间利用等方面的优势和劣势。为了便于太阳能集热器及其水管的安装与维护,提出了一种有维护通道的坡屋顶结构形式。%Considering the integrated structural design of solar collectors and building roof in the building design stage, it is able to satisfy the requirements of solar energy utilization, equipment mainte-nance, roof-space utilization and architectural aesthetics. On the basis of calculating the roof obliquity for best receiving solar radiation, several forms of roof structure are presented, and their advantages and disad-vantages in areas of different latitude are analyzed in roof area, effective area of solar collector and roof space utilization. To be convenient for installation and maintenance of solar collectors and their pipes, a roof structure with maintenance alleyway is presented.

  19. An analytical investigation of the performance of solar collectors as nighttime heat radiators in airconditioning cycles

    Science.gov (United States)

    Jones, C. B.; Smetana, F. O.

    1979-01-01

    It was found that if the upper and lower ends of a collector were opened, large free convention currents may be set up between the collector surface and the cover glass(es) which can result in appreciable heat rejection. If the collector is so designed that both plates surfaces are exposed to convection currents when the upper and lower ends of the collector enclosure are opened, the heat rejection rate is 300 watts sq m when the plate is 13 C above ambient. This is sufficient to permit a collector array designed to provide 100 percent of the heating needs of a home to reject the accumulated daily air conditioning load during the course of a summer night. This also permits the overall energy requirements for cooling to be reduced by at least 15 percent and shift the load on the utility entirely to the nighttime hours.

  20. Spacecraft Design Thermal Control Subsystem

    Science.gov (United States)

    Miyake, Robert N.

    2003-01-01

    This slide presentation reviews the functions of the thermal control subsystem engineers in the design of spacecraft. The goal of the thermal control subsystem that will be used in a spacecraft is to maintain the temperature of all spacecraft components, subsystems, and all the flight systems within specified limits for all flight modes from launch to the end of the mission. For most thermal control subsystems the mass, power and control and sensing systems must be kept below 10% of the total flight system resources. This means that the thermal control engineer is involved in all other flight systems designs. The two concepts of thermal control, passive and active are reviewed and the use of thermal modeling tools are explained. The testing of the thermal control is also reviewed.

  1. Long-term weathering effects on the thermal performance of the solargenics (liquid) solar collector at outdoor conditions. [Marshall Space Flight Center Solar test facility

    Science.gov (United States)

    1979-01-01

    The test procedures and the results obtained during the evaluation of a single-covered liquid solar collector are presented. The tests were performed under outdoor natural conditions. The collector was under stagnation conditions for a total of approximately ten months. The solar collector is a liquid, single-glazed, flat plate collector, and is about 240 inches long, and 3.8 inches in depth.

  2. 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...

  3. 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...

  4. Performance of a solar collector with antireflection treated glass cover

    DEFF Research Database (Denmark)

    Duer, Karsten

    1999-01-01

    The spectral transmittances of two different glass types have been measured in a spectrophotometer. Both glass types have been investigated with and without a Sunarc anti reflection surface (AR surface). The transmittance data for the AR treated samples have been used as input to the AR treatment...... process in order to improve the solar transmittance for the glass samples. A standard flat plate solar collector has been tested in the indoor solar simulator. The purpose of the tests was to evaluate the improvement in collector performance that can be expected by replacing the standard cover...

  5. Indoor test for thermal performance evaluation of Lenox-Honeywell solar collector. [conducted using Marshall Space Flight Center Solar Simulator

    Science.gov (United States)

    Shih, K.

    1977-01-01

    The test procedures used and the test results obtained from an evaluation test program conducted on a double-covered liquid solar collector under simulated conditions are presented. The test article was a flat plate solar collector using liquid as the heat transfer medium. The absorber plate was steel with the copper tubes bonded on the upper surface. The plate was coated with black chrome with an absorptivity factor of .95 and emissivity factor of .12. A time constant test and incident angle modifier test were conducted to determine the transient effect and the incident angle effect on the collector.

  6. Combined solar collector

    OpenAIRE

    Voznyak, O.; Shapoval, S.; Pona, O.; Vengryn, I.

    2014-01-01

    In this article was analyzing the efficiency of the combined solar collector for heating buildings. This enhances the efficiency of solar system by increasing the area of the absorption of solar energy. There are describes the results of the research on solar radiation input on a combined solar collector. Проаналізовано ефективність використання комбінованого сонячного колектора для теплопостачання будівель. Він забезпечує підвищення ефективності геліосистеми за рахунок збільшення площі погли...

  7. High-performance solar collector

    Science.gov (United States)

    Beekley, D. C.; Mather, G. R., Jr.

    1979-01-01

    Evacuated all-glass concentric tube collector using air or liquid transfer mediums is very efficient at high temperatures. Collector can directly drive existing heating systems that are presently driven by fossil fuel with relative ease of conversion and less expense than installation of complete solar heating systems.

  8. Collector-Output Analysis Program

    Science.gov (United States)

    Glandorf, D. R.; Phillips, Robert F., II

    1986-01-01

    Collector-Output Analysis Program (COAP) programmer's aid for analyzing output produced by UNIVAC collector (MAP processor). COAP developed to aid in design of segmentation structures for programs with large memory requirements and numerous elements but of value in understanding relationships among components of any program. Crossreference indexes and supplemental information produced. COAP written in FORTRAN 77.

  9. Realiability Of Heat Supply Subsystem

    Directory of Open Access Journals (Sweden)

    Babiarz Bożena

    2015-11-01

    Full Text Available The article presents the reliability analysis of subsystem of heat supply in the example of 47 thousand inhabitants’ city. The analysis was made on the basis of operational data made available by the Municipal Heating Company, between the years 2001 ÷ 2012. To describe the quantitative reliability of heat supply subsystem reliability indicators are used. Main times between failure and unitary failure rates including the month of their occurrence, type and diameter of the heating network, thermal power region were working out. Knowing the characteristics of the time to repair for the heating network, the reliability of heat supply subsystem for different thermal power region, considering the district heating system configuration can be determined.

  10. Quality and efficiency of solar collectors in Sweden

    Science.gov (United States)

    Wennerholm, H.

    Transparent or translucent insulation materials (TIM's) represent a new class of materials with a high potential for increasing the efficiency of solar thermal conversion systems. A large number of materials have been subjected to theoretical and experimental investigation. If materials that suppress heat losses are transparent to solar radiation, vacuum, certain gases, convection barriers, etc., then they can be regarded as TIM's. Exploratory field and laboratory studies of degraded FEP-film convection barriers in flat plate thermal solar collectors are described. The study related to collectors that had been operating in Sweden for periods of one year to ten years. Both physical, functional (thermal) and chemical aspects of degradation were considered. The report identifies the mistakes made so that they need not be repeated by the solar collector manufacturers in the future.

  11. 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)

  12. LHCb Tag Collector

    CERN Document Server

    Fuente Fernàndez, P; Cousin, N

    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 software management and Nightly Build programs is possible via a Python API. Data are stored in a relational database with the help of an ORM (Object-Relational Mapping) library.

  13. Block storage subsystem performance analysis

    CERN Document Server

    CERN. Geneva

    2016-01-01

    You feel that your service is slow because of the storage subsystem? But there are too many abstraction layers between your software and the raw block device for you to debug all this pile... Let's dive on the platters and check out how the block storage sees your I/Os! We can even figure out what those patterns are meaning.

  14. Shenandoah parabolic dish solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, G.S.

    1985-01-01

    The objectives of the Shenandoah, Georgia, Solar Total Energy System are to design, construct, test, and operate a solar energy system to obtain experience with large-scale hardware systems for future applications. This report describes the initial design and testing activities conducted to select and develop a collector that would serve the need of such a solar total energy system. The parabolic dish was selected as the collector most likely to maximize energy collection as required by this specific site. The fabrication, testing, and installation of the parabolic dish collector incorporating improvements identified during the development testing phase are described.

  15. Shenandoah parabolic dish solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, G.S.

    1985-01-01

    The objectives of the Shenandoah, Georgia, Solar Total Energy System are to design, construct, test, and operate a solar energy system to obtain experience with large-scale hardware systems for future applications. This report describes the initial design and testing activities conducted to select and develop a collector that would serve the need of such a solar total energy system. The parabolic dish was selected as the collector most likely to maximize energy collection as required by this specific site. The fabrication, testing, and installation of the parabolic dish collector incorporating improvements identified during the development testing phase are described.

  16. 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.

  17. Accelerated Testing of Solar Collector Durability

    DEFF Research Database (Denmark)

    Svendsen, Sv Aa Højgaard

    1996-01-01

    A climatic simulator has been build to test the reliability and durability of solar collectors. In the climatic simulator the collector is expåosed to extreme climatic conditions and temperature variations in an accelerated way and during this process the function of the collector is tested...... and the microclimate in the collector box is measured....

  18. 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.

  19. Long term weathering effects on the thermal performance of the sunworks (liquid) solar collector

    Science.gov (United States)

    1979-01-01

    The test procedures used and the results obtained during the evaluation test program of the Sunworks single-covered liquid solar collector are presented. The tests were performed under simulated conditions, following long-term exposure to natural weathering conditions. The sunworks collector is a flat-plate solar collector. The absorber plate is copper with copper tubes bonded by soft solder, and is coated with Enthon selective black with an absorptivity factor of .87 similar to .92 and an emissivity factor of .10 similar to .20. It has a single glass cover of 3/16 inches tempered glass and weighs about 115 pounds. The overall dimensions of the collector are 36 x 84 x 4 inches.

  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. Solar collector manufacturing activity, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-09

    This report presents data provided by US-based manufacturers and importers of solar collectors. Summary data on solar thermal collector shipments are presented for the years 1974 through 1992. Summary data on photovoltaic cell and module shipments are presented for the years 1982 through 1992. Detailed information for solar thermal collectors and photovoltaic cells and modules are presented for 1992. Appendix A describes the survey methodology. Appendix B contains the 1992 survey forms and instructions. Appendices C and D list the companies that responded to the 1992 surveys and granted permission for their names and addresses to appear in the report. Appendix E provides selected tables from this report with data shown in the International System of Units (SI) metric units. Appendix F provides an estimate of installed capacity and energy production from solar collectors for 1992.

  2. Manifold Insulation for Solar Collectors

    Science.gov (United States)

    1982-01-01

    Results of computer analysis of effects of various manifold insulation detailed in 23-page report show that if fluid is distributed to and gathered from array of solar collectors by external rather than internal manifold, effectiveness of manifold insulation has major influence on efficiency. Report describes required input data and presents equations that govern computer model. Provides graphs comparing collector efficiencies for representative manifold sizes and insulations.

  3. 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).

  4. 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.

  5. Simple procedure for predicting long-term average performance of nonconcentration and of concentrating solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Collares-Pereira, M.; Rabl, A.

    1978-06-01

    The Liu and Jordan method of calculating long term average energy collection of flat plate collectors is simplified (by about a factor of 4), and generalized to all collectors, concentration and nonconcentrating. The only meteorological input needed are the long term average daily total hemispherical insolation H/sub h/ on a horizontal surface and, for thermal collectors the average ambient temperature. The collector is characterized by optical efficiency, heat loss (or U-value), heat extraction efficiency, concentration ratio and tracking mode. An average operating temperature is assumed. Interaction with storage can be included by combining the present model with the f-chart method of Beckman, Klein and Duffie. Formulas and examples are presented for five collector types: flat plate, compound parabolic concentrator, concentrator with E.-W. tracking axis, concentrator with polar tracking axis, and concentrator with two axis tracking. The examples show that even for relatively low temperature applications and cloudy climates (50/sup 0/C in New York in February), concentrating collectors can outperform the flat plate. The method has been validated against hourly weather data (with measurements of hemispherical and beam insolation), and has been found to have an average accuracy better than 3% for the long term average radiation available to solar collectors. The suitability of this method for comparison studies is illustrated by comparing in a location independent manner the radiation availability for several collector types or operating conditions: two axis tracking versus one axis tracking; polar tracking axis versus east-west tracking axis; fixed versus tracking flat plate; effect of ground reflectance; and acceptance for diffuse radiation as function of concentration ratio.

  6. Coupled thermal fluid modelling of a low embedded energy solar thermal collector

    Energy Technology Data Exchange (ETDEWEB)

    Corcoran, M.; Gibbons, C. [Cork Institute of Technology (Ireland). Energy Engineering Group

    2004-07-01

    A mathematical model was developed for a forced convection solar hot water system. The solar collector in this study incorporates a honeycombed extruded polycarbonate structure, for both the cover and water channels. The initial section of the program predicts solar radiation (hourly, monthly and yearly) as an input section to the solar collector calculations. As well as determining the collector performance, the model also facilitates changes to the collector physical properties such as dimensions of the channels, selective and non-selective absorbers, material thermal properties, as well as ambient temperature and flow rate, in order to optimise the system design. The results from the program will allow a full parametric study of different collector design criteria, with this polycarbonate structure. The results will be compared to a standard flat plate collector design, to see if this polycarbonate flat plate collector is a more effective design. ISO 9806-2 standards are being used to validate the results, for the parametric study in the lab, under steady state conditions. The final optimum design will then be tested outdoors using the quasi-dynamic conditions set out by the European Standard EN 12975-2. Weather data, obtained from the weather station set up at CIT, will be used as the input for the weather conditions for out door testing. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Gan-Jin; Oh, Yong-Hwan; Ryu, Cheol-Hwi [Hoseo University, Asan (Korea, Republic of); Choi, Ho-Sang [Kyungil University, Gyeongsan, (Korea, Republic of)

    2014-04-15

    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{sup 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{sup 2} and 3.28-3.75 Ω·cm{sup 2} for charge and discharge, respectively. The cell resistance of V-RFB using B current collector was 4.19-4.42Ω·cm{sup 2} and 4.71-5.49Ω·cm{sup 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.

  8. SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS

    Energy Technology Data Exchange (ETDEWEB)

    Steven D. Novack; Dale K. Kotter; Dennis Slafer; Patrick Pinhero

    2008-08-01

    This research explores a new efficient approach for producing electricity from the abundant energy of the sun. A nanoantenna electromagnetic collector (NEC) has been designed, prototyped, and tested. Proof of concept has been validated. The device targets mid-infrared wavelengths where conventional photovoltaic (PV) solar cells do not respond but is abundant in solar energy. The initial concept of designing NEC antennas was based on scaling of radio frequency antenna theory. This approach has proven unsuccessful by many due to not fully understanding and accounting for the optical behavior of materials in the THz region. Also until recent years the nanofabrication methods were not available to fabricate the optical antenna elements. We have addressed and overcome both technology barriers. Several factors were critical in successful implementation of NEC including: 1) frequency-dependent modeling of antenna elements, 2) selection of materials with proper THz properties and 3) novel manufacturing methods that enable economical large-scale manufacturing. The work represents an important step toward the ultimate realization of a low-cost device that will collect as well as convert this radiation into electricity, which will lead to a wide spectrum, high conversion efficiency, and low cost solution to complement conventional PVs.

  9. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham

    2000-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US 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 recollection 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-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

  10. The SPICE Digital Shape Kernel (DSK) Subsystem

    Science.gov (United States)

    Bachman, N. J.

    2017-06-01

    The DSK subsystem is the component of SPICE concerned with detailed shape models. The DSK subsystem enables SPICE-based applications to conveniently and efficiently use detailed shape data in geometry computations performed by SPICE routines.

  11. Solar collector parameter identification from unsteady data by a discrete-gradient optimization algorithm

    Science.gov (United States)

    Hotchkiss, G. B.; Burmeister, L. C.; Bishop, K. A.

    1980-01-01

    A discrete-gradient optimization algorithm is used to identify the parameters in a one-node and a two-node capacitance model of a flat-plate collector. Collector parameters are first obtained by a linear-least-squares fit to steady state data. These parameters, together with the collector heat capacitances, are then determined from unsteady data by use of the discrete-gradient optimization algorithm with less than 10 percent deviation from the steady state determination. All data were obtained in the indoor solar simulator at the NASA Lewis Research Center.

  12. Standard Practice for Generating All-Day Thermal Performance Data for Solar Collectors

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1987-01-01

    1.1 This practice covers a means of generating all-day thermal performance data for flat-plate collectors, concentrating collectors, and tracking collectors. 1.2 The values stated in SI units are to be regarded as the standard. The values given in the parentheses are for information only. 1.3 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.

  13. Holonomic Quantum Computation in Subsystems

    Science.gov (United States)

    Oreshkov, Ognyan

    2009-08-01

    We introduce a generalized method of holonomic quantum computation (HQC) based on encoding in subsystems. As an application, we propose a scheme for applying holonomic gates to unencoded qubits by the use of a noisy ancillary qubit. This scheme does not require initialization in a subspace since all dynamical effects factor out as a transformation on the ancilla. We use this approach to show how fault-tolerant HQC can be realized via 2-local Hamiltonians with perturbative gadgets.

  14. Holonomic quantum computation in subsystems

    OpenAIRE

    Oreshkov, Ognyan

    2009-01-01

    We introduce a generalized method of holonomic quantum computation (HQC) based on encoding in subsystems. As an application, we propose a scheme for applying holonomic gates to unencoded qubits by the use of a noisy ancillary qubit. This scheme does not require initialization in a subspace since all dynamical effects factor out as a transformation on the ancilla. We use this approach to show how fault-tolerant HQC can be realized via 2-local Hamiltonians with perturbative gadgets.

  15. An analytical investigation of the performance of solar collectors as nighttime heat radiators in airconditioning cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.B.; Smetana, F.O.

    1979-03-01

    It was found that if the upper and lower ends of a collector were opened, large free convention currents may be set up between the collector surface and the cover glass(es) which can result in appreciable heat rejection. If the collector is so designed that both plates surfaces are exposed to convection currents when the upper and lower ends of the collector enclosure are opened, the heat rejection rate is 300 watts sq m when the plate is 13 C above ambient. This is sufficient to permit a collector array designed to provide 100 percent of the heating needs of a home to reject the accumulated daily air conditioning load during the course of a summer night. This also permits the overall energy requirements for cooling to be reduced by at least 15 percent and shift the load on the utility entirely to the nighttime hours.

  16. Energy and exergy analysis of PV/T air collectors connected in series

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Swapnil; Solanki, S.C. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Tiwari, Arvind [Department of Design, Production and Management, University of Twente (Netherlands)

    2009-08-15

    In this paper an attempt has been made to derive the analytical expressions for N hybrid photovoltaic/thermal (PV/T) air collectors connected in series. The performance of collectors is evaluated by considering the two different cases, namely, Case I (air collector is fully covered by PV module (glass to glass) and air flows above the absorber plate) and Case II (air collector is fully covered by PV module (glass to glass) and air flows below the absorber plate). This paper shows the detailed analysis of energy, exergy and electrical energy by varying the number of collectors and air velocity considering four weather conditions (a, b, c and d type) and five different cities (New Delhi, Bangalore, Mumbai, Srinagar, and Jodhpur) of India. It is found that the collectors fully covered by PV module and air flows below the absorber plate gives better results in terms of thermal energy, electrical energy and exergy gain. Physical implementation of BIPV system has also been evaluated. If this type of system is installed on roof of building or integrated with building envelope will simultaneously fulfill the electricity generation for lighting purpose and hot air can be used for space heating or drying. (author)

  17. 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.

  18. Development, testing, and certification of Owens-Illinois model SEC-601 solar energy collector system

    Science.gov (United States)

    Parker, J. C.

    1979-01-01

    The final results are presented of the additional development work on the existing air-cooled solar energy collector subsystem for use with solar heating and cooling systems. The report discusses the intended use of the final report, describes the deliverable end items, lists program objectives, relates how they were accomplished, deals with problems encountered during fabrication and testing, and includes a certification statement of performance. The report shows that the products developed are marketable and suitable for public use.

  19. Solar Collector Thermal Power System. Volume 3. Basic Study and Experimental Evaluation of Thermal Train Components

    Science.gov (United States)

    1974-11-01

    the long- lifetime compatibility of sodium and high nickel- chrome alloys (such as Inconel 600) for the thermal train subsystem, an experimental effo...close wound Nichrome V Inconel sheathed resistance heaters were vacuum furnace brazed to the evaporator sections at 1850°F using 82 Au - 18 1. ASTM B...260-BAU-4). Four Inconel sheathed chromel-alumel thermocouples were attached by resistance spot welded Inconel tabs to 40 TABLE VII SOLAR COLLECTOR

  20. 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.

  1. FLPP NGL Structural Subsystems Activity

    Science.gov (United States)

    Jaredson, D.; Ramusat, G.; Appel, S.; Cardone, T.; Persson, J.; Baiocco, P.; Lavelle, F.; Bouilly, Th.

    2012-07-01

    The ESA Future Launchers Preparatory Programme (FLPP) is the basis for new paradigms, investigating the key elements, logic and roadmaps to prepare the development of the safe, reliable and low cost next European Launch Vehicle (LV) for access to space (dubbed NGL - Next Generation LV), with an initial operational capability mid-next decade. In addition to carry cargo to conventional GTO or SSO, the European NGL has to be flexible enough to cope with new pioneering institutional missions as well as the evolving commercial payloads market. This achievement is broached studying three main areas relevant to ELVs: System concepts, Propulsion and Core Technology During the preliminary design activity, a number of design alternatives concerning NGL main structural subsystems have been investigated. Technology is one of the ways to meet the NGL challenges to either improve the performances or to reduce the cost or both. The relevant requirements allow to steer a ‘top-down’ approach for their conception and to propose the most effective technologies. Furthermore, all these technology developments represent a significant ‘bottom-up’ approach investment and concern a large range of activities. The structural subsystems portfolio of the FLPP ‘Core Technology’ activity encompasses major cutting-edge challenges for maturation of the various subsystems leading to reduce overall structural mass, increasing structural margins for robustness, metallic and composite containment of cryogenic propellants, significantly reducing fabrication and operations cost, etc. to derive performing upper and booster stages. Application of concurrent engineering methods will allow developments of performing technology demonstrators in terms of need, demonstration objective, size and cost yielding to safe, low-risk technical approaches for a future development. Potential ability of these advanced structural LV technologies to satisfy the system requirements of the NGL and their current

  2. Hybrid Photovoltaic Thermal (PV/T Air and Water Based Solar Collectors Suitable for Building Integrated Applications

    Directory of Open Access Journals (Sweden)

    Adnan Ibrahim

    2009-01-01

    Full Text Available Problem statement: Experiments have been conducted to investigate the effect of mass flow rates on the electrical, thermal and combined of photovoltaic thermal efficiencies of the hybrid collectors. Approach: Two photovoltaic thermal solar collectors were designed and fabricated. The first collector, known as spiral flow absorber collector, designed to generate hot water and electricity. The second collector, known as single pass rectangular tunnel absorber collector designed to generate hot air and electricity. Both absorber collectors were fixed underneath the flat plate single glazing sheet of polycrystalline silicon PV module. Water was used as a heat transfer medium in spiral flow absorber collector and air for the Single pass rectangular tunnel absorber collector respectively. Results: The experiment results showed that the single flow absorber collector generates combined PV/T efficiency of 64%, electrical efficiency of 11% and power maximum achieved at 25.35 W. Moreover, Single pass rectangular tunnel absorber collector generated combined PV/T efficiency of 55%, electrical efficiency of 10% and maximum power of 22.45 W. Conclusion/Recommendations: The best mass flow rate achieved for spiral flow absorber collector is 0.011 kg sec-1 at surface temperature of 55% and 0.0754 kg sec-1 at surface temperature of 39°C for single pass rectangular collector absorber. It was recommended for PV/T system to further improve its efficiency by optimizing the contact surfaces between the solar panel (photovoltaic module and the tubes underneath and also recommended to use other type of photovoltaic cell such as amorphous silicon cell that posses the black mat surfaces property that will improve it thermal absorption.

  3. Indoor test for thermal performance evaluation of seven Elcam fin-tube solar collector configurations

    Science.gov (United States)

    1979-01-01

    The test procedure used and the results obtained from an evaluation test program conducted to obtain thermal performance data on seven Elcam fin-tube solar collector configurations under simulated conditions are described. These tests were made using the Marshall Space Flight Center solar facilities. The Elcam fin-tube (liquid) solar collectors each consist of an absorber plate 5.9 inches wide by 83 inches long and a type M copper tube of 0.569 inch nominal inside diameter. No cover plate was used with any of the specimens. The uniqueness of each of the seven configurations is described, and tests were performed on each separate configuration.

  4. Survey of solar thermal energy storage subsystems for thermal/electric applications

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C. L.

    1978-08-01

    A survey of the current technology and estimated costs of subsystems for storing the thermal energy produced by solar collectors is presented. The systems considered were capable of producing both electricity and space conditioning for three types of loads: a single-family detached residence, an apartment complex of 100 units, and a city of 30,000 residents, containing both single-family residences and apartments. Collector temperatures will be in four ranges: (1) 100 to 250/sup 0/F (used for space heating and single-cycle air conditioners and organic Rankine low-temperature turbines); (2) 300 to 400/sup 0/F (used for dual-cycle air conditioners and low-temperature turbines); (3) 400 to 600/sup 0/F (using fluids from parabolic trough collectors to run Rankine turbines); (4) 800 to 1000/sup 0/F (using fluids from heliostats to run closed-cycle gas turbines and steam Rankine turbines). The solar thermal energy subsystems will require from 60 to 36 x 10/sup 5/ kWhr (2.05 x 10/sup 5/ to 1.23 x 10/sup 10/ Btu) of thermal storage capacity. In addition to sensible heat and latent heat storage materials, several other media were investigated as potential thermal energy storage materials, including the clathrate and semiclathrate hydrates, various metal hydrides, and heat storage based on inorganic chemical reactions.

  5. 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)

  6. 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.

  7. 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%.

  8. 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

    2015-12-04

    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.

  9. Cassini Mission Sequence Subsystem (MSS)

    Science.gov (United States)

    Alland, Robert

    2011-01-01

    This paper describes my work with the Cassini Mission Sequence Subsystem (MSS) team during the summer of 2011. It gives some background on the motivation for this project and describes the expected benefit to the Cassini program. It then introduces the two tasks that I worked on - an automatic system auditing tool and a series of corrections to the Cassini Sequence Generator (SEQ_GEN) - and the specific objectives these tasks were to accomplish. Next, it details the approach I took to meet these objectives and the results of this approach, followed by a discussion of how the outcome of the project compares with my initial expectations. The paper concludes with a summary of my experience working on this project, lists what the next steps are, and acknowledges the help of my Cassini colleagues.

  10. Indoor test for thermal performance evaluation of the Solaron (air) solar collector

    Science.gov (United States)

    1978-01-01

    The test procedure used and the results obtained from an evaluation test program, conducted to obtain thermal performance data on a Solaron double glazed air solar collector under simulated conditions in a solar simulator are described. A time constant test and incident angle modifier test were also conducted to determine the transient effect and the incident angle effect on the collector. These results and the results of the collector load test are also discussed. The Solaron collector absorber plate is made of 24-gage steel, the coating is baked-on black paint, the cover consists of two sheets of 1/8-inch low-iron tempered glass, and the insulation is one thickness of 3 5/8-inch fiberglass batting.

  11. Thermal performance evaluation of the Suncatcher SH-11 (liquid) solar collector

    Science.gov (United States)

    1980-01-01

    The procedures used and the results obtained during the evaluation test program on the Solar Unlimited, Inc., Suncatcher SH-11 (liquid) solar collector are presented. The flat-plate collector case assembly is made of .08 inch aluminum 3003 H14 riveted with fiberglass board insulation. The absorber consists of collared aluminum fins mechanically bonded to 3/8 inch copper tubing and coated with 3M Nextel black. Water is used as the working fluid. The glazing is made of a single glass, 1/8 inch water white, tempered and antireflective. The collector weight is 85 pounds with overall external dimensions of about 35.4 in x 82.0 in x 4.0 in. Thermal performance data on the Solar Unlimited Suncatcher SH-11 solar collector under simulated conditions were conducted using the MSFC Solar Simulator.

  12. Experiments and simulations on a thermosyphon solar collector with integrated storage

    Science.gov (United States)

    Toninelli, P.; Mariani, A.; Del, D., Col

    2015-11-01

    This paper deals with the thermal behaviour of a new type of flat solar collector that integrates the fluid storage tank. Often the main limitation of the solar thermosyphon installations is the prohibition to adopt external storage tanks due to their impact, especially for historical centres of particular architectural significance. To avoid this issue, a new system, that includes the collector and the storage, has been developed. This new apparatus works as a thermosyphon: it is possible to take advantage of the natural convection to avoid using a pump. Experimental tests have been conducted in such a collector with and without the absorbing plate. Furthermore, CFD simulations are reported to analyze in detail the dynamic thermal performance of the innovative solar collector and a good-agreement with the experimental tests has been found. Finally, both in numerical simulations and in experimental data the thermosyphon effect has been verified, obtaining the desired water temperature for domestic applications.

  13. Giada improved calibration of measurement subsystems

    Science.gov (United States)

    Della Corte, V.; Rotundi, A.; Sordini, R.; Accolla, M.; Ferrari, M.; Ivanovski, S.; Lucarelli, F.; Mazzotta Epifani, E.; Palumbo, P.

    2014-12-01

    GIADA (Grain Impact Analyzer and Dust Accumulator) is an in-situ instrument devoted to measure the dynamical properties of the dust grains emitted by the comet. An Extended Calibration activity using the GIADA Flight Spare Model has been carried out taking into account the knowledge gained through the analyses of IDPs and cometary samples returned from comet 81P/Wild 2. GIADA consists of three measurement subsystems: Grain Detection System, an optical device measuring the optical cross-section for individual dust; Impact Sensor an aluminum plate connected to 5 piezo-sensors measuring the momentum of impacting single dust grains; Micro Balance System measuring the cumulative deposition in time of dust grains smaller than 10 μm. The results of the analyses on data acquired with the GIADA PFM and the comparison with calibration data acquired during the pre-launch campaign allowed us to improve GIADA performances and capabilities. We will report the results of the following main activities: a) definition of a correlation between the 2 GIADA Models (PFM housed in laboratory and In-Flight Model on-board ROSETTA); b) characterization of the sub-systems performances (signal elaboration, sensitivities, space environment effects); c) new calibration measurements and related curves by means of the PFM model using realistic cometary dust analogues. Acknowledgements: GIADA was built by a consortium led by the Univ. Napoli "Parthenope" & INAF-Oss. Astr. Capodimonte, IT, in collaboration with the Inst. de Astrofisica de Andalucia, ES, Selex-ES s.p.a. and SENER. GIADA is presently managed & operated by Ist. di Astrofisica e Planetologia Spaziali-INAF, IT. GIADA was funded and managed by the Agenzia Spaziale Italiana, IT, with a support of the Spanish Ministry of Education and Science MEC, ES. GIADA was developed from a University of Kent, UK, PI proposal; sci. & tech. contribution given by CISAS, IT, Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and USA. We thank

  14. The use of collector efficiency test results in long term performance calculations. Revisions and clarifications in view of proper collector characterization and inter comparison

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Maria Joao; Horta, Pedro; Mendes, Joao Farinha [INETI - Inst. Nacional de Engenharia Tecnologia e Inovacao, IP, Lisboa (Portugal); Collares Pereira, Manuel; Carbajal, Wildor Maldonado [AO SOL, Energias Renovaveis, S.A., Samora Correia (Portugal)

    2008-07-01

    There are a growing number of solar thermal collector types: flat plates, evacuated tubes with and without backing reflectors and different tubular spacing, low concentration collectors, using different types of concentrating optics. These different concepts and designs all compete to be more efficient or simply cheaper, easier to operate, etc. at ever higher temperatures, and even to extend the use of solar thermal energy in other applications beyond the most common water heating for domestic purposes. This means that there is a growing need for the existing and future simulation tools to be as accurate as possible in the treatment of these different collector types, to allow for the proper dimensioning of solar thermal systems as well as the proper comparison of different collector technologies for a given application. This paper develops a systematic approach to the problem of the proper handling of solar radiation available to each collector type. The proposed methodology subdivides radiation in its different components, folding that with the information available from efficiency curve tests (steady state) for each collector type and the way the optics of each particular case transforms and uses the incident solar radiation. The suggestions made will hopefully be taken at the level of the testing standards themselves, rendering them more complete and general. (orig.)

  15. 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...

  16. Thermal advantage of tracking solar collectors under Danish weather conditions

    DEFF Research Database (Denmark)

    Andersen, Elsa; Dragsted, Janne; Furbo, Simon

    2010-01-01

    . 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......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...

  17. A reference heat source for solar collector thermal testing

    Science.gov (United States)

    Harrison, S. J.; Bernier, M. A.

    1984-12-01

    A direct-comparison reference heat source (RHS), used for testing liquid-based solar collectors, is described. A major advantage of the RHS is its capability to measure the product of mass flow and specific heat directly in the test loop. Calibration tests are performed on two reference heat sources over a range of flowrates and inlet temperatures normally encountered in flat-plate solar collector testing (10 C to 95 C). It is shown that at low flowrates (less than or equal to 0.008 kg/s), localized boiling may introduce errors if the heater power density is not reduced as well, whereas operation at flowrates greater than 0.05 kg/s reduces the temperature rise across the RHS, increasing temperature measurement uncertainty. To achieve satisfactory results with an RHS, a stable inlet temperature, good flowrate control, and regulation of the power supplied to the heater are required.

  18. Automated Verification of Practical Garbage Collectors

    CERN Document Server

    Hawblitzel, Chris

    2010-01-01

    Garbage collectors are notoriously hard to verify, due to their low-level interaction with the underlying system and the general difficulty in reasoning about reachability in graphs. Several papers have presented verified collectors, but either the proofs were hand-written or the collectors were too simplistic to use on practical applications. In this work, we present two mechanically verified garbage collectors, both practical enough to use for real-world C# benchmarks. The collectors and their associated allocators consist of x86 assembly language instructions and macro instructions, annotated with preconditions, postconditions, invariants, and assertions. We used the Boogie verification generator and the Z3 automated theorem prover to verify this assembly language code mechanically. We provide measurements comparing the performance of the verified collector with that of the standard Bartok collectors on off-the-shelf C# benchmarks, demonstrating their competitiveness.

  19. LTE RF subsystem power consumption modeling

    DEFF Research Database (Denmark)

    Musiige, Deogratius; Vincent, Laulagnet; Anton, François;

    2012-01-01

    This paper presents a new power consumption emulation model, for all possible scenarios of the RF subsystem, when transmitting a LTE signal. The model takes the logical interface parameters, Tx power, carrier frequency and bandwidth between the baseband and RF subsystem as inputs to compute the p...

  20. Efficient chaotic based satellite power supply subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Ramos Turci, Luiz Felipe [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail: felipeturci@yahoo.com.br; Macau, Elbert E.N. [National Institute of Space Research (Inpe), Sao Jose dos Campos, SP (Brazil)], E-mail: elbert@lac.inpe.br; Yoneyama, Takashi [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail: takashi@ita.br

    2009-10-15

    In this work, we investigate the use of the Dynamical System Theory to increase the efficiency of the satellite power supply subsystems. The core of a satellite power subsystem relies on its DC/DC converter. This is a very nonlinear system that presents a multitude of phenomena ranging from bifurcations, quasi-periodicity, chaos, coexistence of attractors, among others. The traditional power subsystem design techniques try to avoid these nonlinear phenomena so that it is possible to use linear system theory in small regions about the equilibrium points. Here, we show that more efficiency can be drawn from a power supply subsystem if the DC/DC converter operates in regions of high nonlinearity. In special, if it operates in a chaotic regime, is has an intrinsic sensitivity that can be exploited to efficiently drive the power subsystem over high ranges of power requests by using control of chaos techniques.

  1. Particle deposition to protruding local sinks adhering on a collector surface

    NARCIS (Netherlands)

    vanderMei, HC; Busscher, HJ; Bos, R.R.M.

    1996-01-01

    In this paper, we measured the local initial deposition rates of streptococci to adhering actinomyces, acting as protruding local sinks on a glass collector, as a function of the actinomyces density in a parallel plate flow chamber. The local initial deposition rates, i.e., deposition in the vicinit

  2. Indoor test for thermal performance evaluation of Libbey-Owens-Ford solar collector. [using a solar simulator

    Science.gov (United States)

    Shih, K.

    1977-01-01

    The thermal performance of a flat plate solar collector that uses liquid as the heat transfer medium was investigated under simulated conditions. The test conditions and thermal performance data obtained during the tests are presented in tabular form, as well as in graphs. Data obtained from a time constant test and incident angle modifier test, conducted to determine transient effect and the incident angle effect on the collector, are included.

  3. 温和地区阳台壁挂式平板型太阳能热水器水量配比优化%Optimization of tank-volume-to-collector-area ratio for balcony wall-mounted flat-plate solar water heater in mild region of China

    Institute of Scientific and Technical Information of China (English)

    魏生贤; 胡粉娥; 晏翠琼

    2016-01-01

    thermal performance of the flat-plate type solar energy water heater has been studied globally. In order to ensure the efficient operation of the solar water heater and user's demand to the terminal temperature of a tank, the countries all over the world with different climate have given different recommended value for water-mass-to-collector-area ratio (the ratio is abbreviated as MAR) of the flat-plate solar water heater. However, China has a vast territory and its climate is complex. The value range of recommended value from literatures is too large to be used to practical application. The main residential buildings in large and medium-sized cities are mostly high-rise buildings. The solar water heater installed on roof can only meet hot water use for the top six to eight floors. The application of the balcony wall-mounted solar water heater is one of the effective ways to solve hot water needs for the rest of users in high-rise buildings. Based on the typical meteorological data of nine cities in mild region of China, the values of MAR of the balcony wall-mounted flat-plate solar water heater have been calculated by using the established mathematical model. The water tank terminal temperature of 60℃, the collector angle of 60°-90° and the azimuth angle of 0-90° were used in model analysis. Calculation results for south-facing balcony wall-mounted solar water heater in mild region showed that the appropriate MAR of spring, summer, autumn, winter and the whole year was 28-51, 21-41, 31-53, 37-57 and 31-47 kg/m2, respectively. For convenience of practical application, the linear regression relation between seasonal and annual average MAR and the tilt angle for south-facing balcony wall-mounted solar water heater. The correlation coefficients between them were greater than 0.99. In this paper, we introduced a new concept “azimuth factor of MAR” which was easy to calculate MAR for the collector with different azimuth angle. For the non-south-facing balcony wall

  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 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...... agreement with the measured efficiencies....

  5. 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...

  6. Long-term weathering effects on the thermal performance of the Libbey-Owens-Ford (liquid) solar collector

    Science.gov (United States)

    1979-01-01

    Thermal performance tests were conducted on the Libbey-Owens-Ford liquid collector, following long term exposure to natural weathering conditions. Visual inspection of the collector, prior to the retest, indicated noticeable clouding of the inner cover glass, probably resulting from outgassing of the insulation. The absorber plate also showed some discoloration. The test results indicated that performance degradation had occurred at inlet temperatures significantly above ambient. The change in the slope of the efficiency curve, from the original data, is a direct indicator of an increase in the collector heat loss coefficient.

  7. Optical design for EUV lithography source collector

    Institute of Scientific and Technical Information of China (English)

    Shuqing Zhang; Qi Wang; Dongyuan Zhu; Runshun Li; Chang Liu

    2011-01-01

    @@ Wolter I collector is the best collector for extreme ultraviolet (EUV) lithography, which has a series of nested mirrors.It has high collection efficiency and can obtain more uniform intensity distribution at the intermediate focus (IF).A new design with the calculation sequence from the outer mirror to the inner one on the premise of satisfying the requirements of the collector is introduced.Based on this concept, a computer program is established and the optical parameters of the collector using the program is calculated.The design results indicate that the collector satisfies all the requirements.%Wolter I collector is the best collector for extreme ultraviolet (EUV) lithography, which has a series of nested mirrors. It has high collection efficiency and can obtain more uniform intensity distribution at the intermediate focus (IF). A new design with the calculation sequence from the outer mirror to the inner one on the premise of satisfying the requirements of the collector is introduced. Based on this concept, acomputer program is established and the optical parameters of the collector using the program is calculated.The design results indicate that the collector satisfies all the requirements.

  8. Design and evaluation of a computer controlled solar collector simulator

    Science.gov (United States)

    Kotas, J. F.; Wood, B. D.

    1980-11-01

    A computer-controlled system has been developed to simulate the thermal processes of a flat-plate solar collector. The simulator is based on four water heaters of capacities of 1.5, 2.5, 5.0 and 5.0 kW providing a maximum design output of 14.0 kW which are controlled by a Nova 3 minicomputer, which also monitors temperatures in the fluid stream. Measurements have been obtained of the steady-state operating values and time constants of the individual heaters at different flow rates in order to utilize effectively their thermal outputs. Software was designed to control the heater system so the total thermal output closely approximates that of an actual heater array, utilizing steady-state or dynamic control modes. Simulation of the heat output of a previously tested collector has resulted in simulated values differing from actual output by a maximum of 3% under identical operating conditions, thus indicating that the simulator represents a viable alternative to the testing of a large field of collectors.

  9. 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.

  10. 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

  11. Bounds on entanglement in qudit subsystems

    OpenAIRE

    Kendon, Vivien M.; Zyczkowski, Karol; Munro, William J.

    2002-01-01

    The entanglement in a pure state of N qudits (d-dimensional distinguishable quantum particles) can be characterised by specifying how entangled its subsystems are. A generally mixed subsystem of m qudits is obtained by tracing over the other N-m qudits. We examine the entanglement in the space of mixed states of m qudits. We show that for a typical pure state of N qudits, its subsystems smaller than N/3 qudits will have a positive partial transpose and hence are separable or bound entangled. ...

  12. Effect of Position of Upper Connecting Pipe on the Tank on Thermal Performance of Domestic Solar Water Heaters with a Vertical Storage Tank and Flat-plate Collectors%上循环管位置对平板型家用太阳能热水器性能的影响

    Institute of Scientific and Technical Information of China (English)

    朱海威; 高文峰; 林文贤; 刘滔; 李泽东

    2014-01-01

    In this paper,the domestic solar water heater with a vertical storage tank and a flat-plat collector,which is commercially available and popular in the market,was experimentally in-vestigated.Firstly, natural circulation experiment platform of flat plate domestic solar water heater was set up.The effect of two different positions of upper connecting pipe on temperature variation in the water tank during the heating stage in the daytime and thermal performances was measured.Through the analysis of test data,The difference of temperature stratification in the water tank with upper connecting pipe at high position and at low position were studied re-spectively.Also the instantaneous efficiency in 10 minutes was defined and compared.The results showed that there was better temperature stratification in the water tank when it’s upper con-necting pipe at high position during heating stage.In addition,the instantaneous efficiency of so-lar water heater,which water tank with upper connecting pipe at high location under the natural circulation condition was superior to the water tank with upper circulation pipe at low position.%对一种常见的平板型立式储热水箱家用太阳能热水器进行试验分析。搭建了自然循环平板型家用太阳能热水器的实验平台。测量了两种不同位置的上循环管对白天加热阶段储热水箱温度变化及对热性能的影响,通过测试数据分析对比了高、低位上循环管循环时,水箱内温度变化、分层状况,定义了十分钟内的平均效率,并进行了比较。结果表明:储热水箱升温阶段采用高位上循环管的水箱内部出现较好的水温分层;高位上循环管热水器的自然循环瞬时效率比低位上循环管热水器的瞬时效率高。

  13. Investigating the collector efficiency of silver nanofluids based direct absorption solar collectors

    OpenAIRE

    Chen, M.; He, Y.; J. Zhu; Wen, D

    2016-01-01

    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 increa...

  14. Combined photovoltaic and thermal hybrid collector systems

    Energy Technology Data Exchange (ETDEWEB)

    Kern, E.C. Jr.; Russell, M.C.

    1978-01-01

    Solar energy collectors that produce both electric and thermal energy are an attractive alternative to individual thermal and photovoltaic collectors for certain applications and climates. Economic results from a system analysis indicate that hybrid collector systems are attractive in small buildings that have substantial heating loads. Passively cooled photovoltaic panels are best suited for structures located in regions where year-round air conditioning and small, low-grade, thermal energy demands predominate. Hybrid collectors are to be tested according to ASHRAE standards and a full-system experiment incorporating a photovoltaic array installed at the Solar Energy Research Facility of the University of Texas will be conducted by Lincoln Laboratory.

  15. Fog collectors and collection techniques

    Science.gov (United States)

    Höhler, I.; Suau, C.

    2010-07-01

    The earth sciences taught that due to the occurrence of water in three phases: gas, liquid and solid, solar energy keeps the hydrological cycle going, shaping the earth surface while regulating the climate and thus allowing smart technologies to interfere in the natural process by rerouting water and employing its yield for natural and human environments’ subsistence. This is the case of traditional fog collectors implemented by several researchers along the Atacama Desert since late ’50s such as vertical tensile mesh or macro-diamonds structures. Nevertheless, these basic prototypes require to be upgraded, mainly through new shapes, fabrics and frameworks’ types by following the principles of lightness, transformability, portability and polyvalence. The vertical canvas of conventional fog collectors contain too much stressed at each joints and as result it became vulnerable. Our study constitutes a research by design of two fog-trap devices along the Atacama Desert. Different climatic factors influence the efficiency of fog harvesting. In order to increase yield of collected fog water, we need to establish suitable placements that contain high rates of fog’s accumulation. As important as the location is also the building reliability of these collectors that will be installed. Their frames and skins have to be adjustable to the wind direction and resistant against strong winds and rust. Its fabric need to be more hydrophobic, elastic and with light colours to ease dripping/drainage and avoid ultra-violet deterioration. In addition, meshes should be well-tensed and frames well-embraced too. In doing so we have conceived two fog collectors: DropNet© (Höhler) and FogHive© (Suau). These designs explore climatic design parameters combined with the agile structural principles of Tensegrity and Geodesic widely developed by Bucky Fuller and Frei Otto. The research methods mainly consisted of literature review; fieldwork; comparative analysis of existing fog

  16. Bounds on entanglement in qudit subsystems

    CERN Document Server

    Kendon, V M; Munro, W J; Kendon, Vivien M; Zyczkowski, Karol; Munro, William J

    2002-01-01

    The entanglement in a pure state of N qudits (d-dimensional distinguishable quantum particles) can be characterised by specifying how entangled its subsystems are. A generally mixed subsystem of m qudits is obtained by tracing over the other N-m qudits. We examine the entanglement in this mixed space of m qudits. We show that for a typical pure state of N qudits, its subsystems smaller than N/3 qudits will have a positive partial transpose and hence are separable or bound entangled. Additionally, our numerical results show that the probability of finding entangled subsystems smaller than N/3 falls exponentially in the dimension of the Hilbert space. The bulk of pure state Hilbert space thus consists of highly entangled states with multipartite entanglement encompassing at least a third of the qudits in the pure state.

  17. Automated solar collector installation design

    Energy Technology Data Exchange (ETDEWEB)

    Wayne, Gary; Frumkin, Alexander; Zaydman, Michael; Lehman, Scott; Brenner, Jules

    2014-08-26

    Embodiments may include systems and methods to create and edit a representation of a worksite, to create various data objects, to classify such objects as various types of pre-defined "features" with attendant properties and layout constraints. As part of or in addition to classification, an embodiment may include systems and methods to create, associate, and edit intrinsic and extrinsic properties to these objects. A design engine may apply of design rules to the features described above to generate one or more solar collectors installation design alternatives, including generation of on-screen and/or paper representations of the physical layout or arrangement of the one or more design alternatives.

  18. Long term weathering effects on the thermal performance of the solaron (air) solar collector

    Science.gov (United States)

    1979-01-01

    The test procedures and the results obtained during the evaluation test program on the Solaron Corporation air-type solar collector are presented. The tests were performed under simulated conditions, following long-term exposure to natural weathering conditions. The Solaron Model 2001, air-type solar collector has a gross area of 19 square feet and the weight is 160 pounds. The absorber plate is made of 24-gage steel, the coating is baked-on black paint, the cover consists of two sheets of 1/8-inch low-iron tempered glass, and the insulation is one thickness of 3 5/8-inch fiberglass batting.

  19. CONC/11: A computer program for calculating the performance of dish-type solar thermal collectors and power systems

    Science.gov (United States)

    Jaffe, L. D.

    1984-01-01

    The CONC/11 computer program designed for calculating the performance of dish-type solar thermal collectors and power systems is discussed. This program is intended to aid the system or collector designer in evaluating the performance to be expected with possible design alternatives. From design or test data on the characteristics of the various subsystems, CONC/11 calculates the efficiencies of the collector and the overall power system as functions of the receiver temperature for a specified insolation. If desired, CONC/11 will also determine the receiver aperture and the receiver temperature that will provide the highest efficiencies at a given insolation. The program handles both simple and compound concentrators. The CONC/11 is written in Athena Extended FORTRAN (similar to FORTRAN 77) to operate primarily in an interactive mode on a Sperry 1100/81 computer. It could also be used on many small computers. A user's manual is also provided for this program.

  20. CONC/11: a computer program for calculating the performance of dish-type solar thermal collectors and power systems

    Energy Technology Data Exchange (ETDEWEB)

    Jaffe, L. D.

    1984-02-15

    CONC/11 is a computer program designed for calculating the performance of dish-type solar thermal collectors and power systems. It is intended to aid the system or collector designer in evaluating the performance to be expected with possible design alternatives. From design or test data on the characteristics of the various subsystems, CONC/11 calculates the efficiencies of the collector and the overall power system as functions of the receiver temperature for a specified insolation. If desired, CONC/11 will also determine the receiver aperture and the receiver temperature that will provide the highest efficiencies at a given insolation. The program handles both simple and compound concentrators. CONC/11 is written in Athena Extended Fortran (similar to Fortran 77) to operate primarily in an interactive mode on a Sperry 1100/81 computer. It could also be used on many small computers.

  1. Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume IV. Receiver subsystem. [10-MW Pilot Plant and 100-MW Commercial Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-11-01

    The conception, design, and testing of the receiver subsystem proposed by the McDonnell Douglas/Rocketdyne Receiver team for the DOE 10-MW Pilot Plant and the 100-MW Commercial Plant are described. The receiver subsystem consists of the receiver unit, the tower on which the receiver unit is mounted above the collector field, and the supporting control and instrumentation equipment. The plans for implementation of the Pilot Plant are given including the anticipated schedule and production plan (procurement, installation, checkout, and maintenance). Specifications for the performance, design, and test requirements for the Pilot Plant receiver subsystem are included. (WHK)

  2. Optimization of dish solar collectors

    Science.gov (United States)

    Jaffe, L. D.

    1983-01-01

    Methods for optimizing parabolic dish solar collectors and the consequent effects of various optical, thermal, mechanical, and cost variables are examined. The most important performance optimization is adjusting the receiver aperture to maximize collector efficiency. Other parameters that can be adjusted to optimize efficiency include focal length, and, if a heat engine is used, the receiver temperature. The efficiency maxima associated with focal length and receiver temperature are relatively broad; it may, accordingly, be desirable to design somewhat away from the maxima. Performance optimization is sensitive to the slope and specularity errors of the concentrator. Other optical and thermal variables affecting optimization are the reflectance and blocking factor of the concentrator, the absorptance and losses of the receiver, and, if a heat engine is used, the shape of the engine efficiency versus temperature curve. Performance may sometimes be improved by use of an additional optical element (a secondary concentrator) or a receiver window if the errors of the primary concentrator are large or the receiver temperature is high. Previously announced in STAR as N83-19224

  3. Evaluation of Test Method for Solar Collector Efficiency

    OpenAIRE

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

    2006-01-01

    The test method of the standard EN12975-2 (European Committee for Standardization, 2004) is used by European test laboratories to determine the efficiency of solar collectors. In the test methods the mean solar collector fluid temperature in the solar collector, Tm is determined by the approximated equation where Tin is the inlet temperature to the collector and Tout is the outlet temperature from the collector. The specific heat of the solar collector fluid is in the test method as an approx...

  4. 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...

  5. Formal Derivation of Concurrent Garbage Collectors

    NARCIS (Netherlands)

    Pavlovic, Dusko; Pepper, Peter; Smith, Douglas R.

    Concurrent garbage collectors are notoriously difficult to implement correctly. Previous approaches to the issue of producing correct collectors have mainly been based on posit-and-prove verification or on the application of domain-specific templates and transformations. We show how to derive the

  6. Design review of a liquid solar collector

    Science.gov (United States)

    Wiesewmaier, B. L.

    1979-01-01

    Report documents procedures, results, and recommendations for in-depth analysis of problems with liquid-filled version of concentric-tube solar collector. Problems are related to loss of vacuum and/or violent fracture of collector elements, fluid leakage, freezing, flow anomalies, manifold damage, and other component failures.

  7. 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.

  8. Cleaner for Solar-Collector Covers

    Science.gov (United States)

    Frickland, P. O.; Cleland, E. L.

    1983-01-01

    Simple self-contained cleaning system proposed for solar collectors or solar-collector protective domes. Perforated transparent plastic cap attached to top of protective dome in heliostat solar-energy collection system distributes cleaning fluid over surface of dome without blocking significant fraction of solar radiation.

  9. Pioneer CESA Guidance Project: Data Collectors Guide.

    Science.gov (United States)

    Bryant, Brenda; Andrews, Theodore

    The purpose of this guide is to assist trained data collectors in the use of the "Performance-Based Counselor Certification Model for the State of Georgia." The guidelines are intended to clarify the process rather than to limit the data collector to a confining set of definitions. In addition, the guide discusses specific school…

  10. 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 th...

  11. Synthetic fiber air collectors for agricultural uses

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.

    Details are given on an innovative air collector system made of porous black synthetic fibers to take in air and absorb solar radiation to heat it. Synthetic fiber collectors are unexpensive, they are characterized by their efficient heat transfers, good working properties, and wind resistance. Excessive heating, condensates, and dusts are avoided using them. Schematic sketches facilitate access to the fibrous structure, uses, design and construction of solar air collectors made of Nicolon fibers. Temperature and collector capacity measuring results are shown in a diagram. Details are given on a small-scale solar drier drying herbs (solar collector system with a 36 m/sup 2/ fibrous absorber surface) as well as on experiences gained in the operation of more than 20 solar driers of the kind described. (HWJ).

  12. Design approaches for solar industrial process-heat systems: nontracking and line-focus collector technologies

    Energy Technology Data Exchange (ETDEWEB)

    Kutscher, C.F.; Davenport, R.L.; Dougherty, D.A.; Gee, R.C.; Masterson, P.M.; May, E.K.

    1982-08-01

    The design methodology for solar industrial process heat systems is described, and an overview is given of the use of solar energy in industry. A way to determine whether solar energy makes sense for a particular application is described. The basic system configurations used to supply hot water or steam are discussed, and computer-generated graphs are supplied that allow the user to select a collector type. Detailed energy calculations are provided, including the effects of thermal losses and storage. The selection of subsystem components is described, and control systems, installation and start-up details, economics, and safety and environmental issues are explained. (LEW)

  13. On similitude law of sub-systems

    Institute of Scientific and Technical Information of China (English)

    Zach Liang; George C. Lee

    2006-01-01

    Based on Buckingham's π-Theorem, dimensional analysis has achieved considerable success over the past near-century. Model testing has long been a powerful tool in both scientific studies and engineering applications. However,the prototype objects are becoming more and more complicated nowadays, and many of the prototype systems can contain several sub-systems. The conventional theories on model-prototype similarity and dimensional analysis have only limited application since the π -Theorem itself does not distinguish between the original system and subsystems. This is particularly true in the field of structural dynamics, where the structure is often modeled as a multi-degree-of-freedom system. In this paper, we attempt to show that, if a system can be decoupled into several nontrivial subsystems, then, in each subsystem,the number of π -terms will be reduced and therefore simplify the model testing. On the other hand, if a system cannot be decoupled into subsystems, then using model testing with reduced π -term analysis, both experimentally and theoretically,may introduce severe errors.

  14. 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.

  15. Embedded Thermal Control for Spacecraft Subsystems Miniaturization

    Science.gov (United States)

    Didion, Jeffrey R.

    2014-01-01

    Optimization of spacecraft size, weight and power (SWaP) resources is an explicit technical priority at Goddard Space Flight Center. Embedded Thermal Control Subsystems are a promising technology with many cross cutting NSAA, DoD and commercial applications: 1.) CubeSatSmallSat spacecraft architecture, 2.) high performance computing, 3.) On-board spacecraft electronics, 4.) Power electronics and RF arrays. The Embedded Thermal Control Subsystem technology development efforts focus on component, board and enclosure level devices that will ultimately include intelligent capabilities. The presentation will discuss electric, capillary and hybrid based hardware research and development efforts at Goddard Space Flight Center. The Embedded Thermal Control Subsystem development program consists of interrelated sub-initiatives, e.g., chip component level thermal control devices, self-sensing thermal management, advanced manufactured structures. This presentation includes technical status and progress on each of these investigations. Future sub-initiatives, technical milestones and program goals will be presented.

  16. Experimental investigation of a nanofluid absorber employed in a low-profile, concentrated solar thermal collector

    Science.gov (United States)

    Li, Qiyuan; Zheng, Cheng; Mesgari, Sara; Hewakuruppu, Yasitha L.; Hjerrild, Natasha; Crisostomo, Felipe; Morrison, Karl; Woffenden, Albert; Rosengarten, Gary; Scott, Jason A.; Taylor, Robert A.

    2015-12-01

    Recent studies [1-3] have demonstrated that nanotechnology, in the form of nanoparticles suspended in water and organic liquids, can be employed to enhance solar collection via direct volumetric absorbers. However, current nanofluid solar collector experimental studies are either relevant to low-temperature flat plate solar collectors (100 °C) indoor laboratory-scale concentrating solar collectors [1, 5]. Moreover, many of these studies involve in thermal properties of nanofluid (such as thermal conductivity) enhancement in solar collectors by using conventional selective coated steel/copper tube receivers [6], and no full-scale concentrating collector has been tested at outdoor condition by employing nanofluid absorber [2, 6]. Thus, there is a need of experimental researches to evaluate the exact performance of full-scale concentrating solar collector by employing nanofluids absorber at outdoor condition. As reported previously [7-9], a low profile (solar thermal concentrating collector was designed and analysed which can potentially supply thermal energy in the 100-250 °C range (an application currently met by gas and electricity). The present study focuses on the design and experimental investigation of a nanofluid absorber employed in this newly designed collector. The nanofluid absorber consists of glass tubes used to contain chemically functionalized multi-walled carbon nanotubes (MWCNTs) dispersed in DI water. MWCNTs (average diameter of 6-13 nm and average length of 2.5-20 μm) were functionalized by potassium persulfate as an oxidant. The nanofluids were prepared with a MCWNT concentration of 50 +/- 0.1 mg/L to form a balance between solar absorption depth and viscosity (e.g. pumping power). Moreover, experimentally comparison of the thermal efficiency between two receivers (a black chrome-coated copper tube versus a MWCNT nanofluid contained within a glass tubetube) is investigated. Thermal experimentation reveals that while the collector efficiency

  17. 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.

  18. Thermal performance of solar air collector with transparent honeycomb made of glass tube

    Institute of Scientific and Technical Information of China (English)

    ZHANG ZhiQiang; ZUO Ran; LI Ping; SU WenJia

    2009-01-01

    Transparent honeycomb structure with thin-walled glass tube as the honeycomb unit is designed and applied to a flat-plate solar air collector.Experiments are performed for solar collectors with six different honeycomb sizes.The emphasis is to study the effects of diameter and aspect ratio of the honeycomb unit on the transmittance and efficiency of the solar collector.It is shown that for the same diameter but different aspect ratios,there are large temperature differences between the collector's exits;the smaller the aspect ratio,the larger the exit temperature,with a maximum difference of 10℃;for the same aspect ratio but different diameters,the temperature differences are small;the maximum temperature difference between the collectors with and without honeycombs is 12℃.A theoretical expression for the honeycomb transmittance is derived with a simplified method.The result shows that the honeycomb transmittance is only related with the aspect ratio and the materials' optical properties but not the actual size of the honeycomb.

  19. 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.

  20. On the SOR method with overlapping subsystems

    Science.gov (United States)

    Maleev, A. A.

    2006-06-01

    A description is given of the iterative Jacobi method with overlapping subsystems and the corresponding Gauss-Seidel method. Similarly to the classical case, a generalized SOR method with overlapping subsystems is constructed by introducing an relaxation parameter. The concept of a ω-consistent matrix is defined. It is shown that, with the optimal choice of the parameter, the theory developed by Young remains valid for ω-consistent matrices. This implies certain results for ω-consistent H-matrices. The theoretical conclusions obtained in the paper are supported by numerical results.

  1. Comparison between a simple solar collector accumulator and a conventional accumulator

    Energy Technology Data Exchange (ETDEWEB)

    Fasulo, AmIlcar [University National of San Luis, San Luis (Argentina); University National of Rio IV, Rio Cuarto (Argentina); Follari, Jorge [University National of San Luis, San Luis (Argentina); Barral, Jorge [University National of Rio IV, Rio Cuarto (Argentina)

    2001-07-01

    In dry regions with abundant solar radiation at Southern latitudes between 30 and 40deg, such as the central-western part of Argentina, it is possible to obtain domestic hot water by means of simple integral collector accumulator systems, which are less expensive than the classical flat plate active systems. The experimental assessment of two solar accumulator collector systems yielding 300 1 of hot water daily is reported in this work. Daily diurnal global efficiency and nocturnal thermal losses have been systematically determined over a 5-month period, from austral summer to austral winter. The results of these systems were compared with the results obtained from a high quality thermosyphon solar system composed of a flat plate collector and its corresponding insulated storage tank, tested at the same time. The experiments were carried out by measuring the climatic variables, temperatures in different parts of the collectors, and mass flow rates of water, during the test days. Based on these measurements, the behaviour of the systems was analysed by comparing exit temperatures, heat losses, and delivered useful energy. An economic evaluation was made considering the investment time recovery through the savings the system could provide working with different conventional sources of energy. The systems proved to work efficiently, although some improvements should be made on the semitransparent thermal insulation in order to enhance its winter performance. (Author)

  2. 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.

  3. Performance after weathering of a liquid solar collector

    Science.gov (United States)

    1979-01-01

    Results from retesting of liquid solar collector described in "Performance evaluation of liquid collector" (M-FS-23931), after long term exposure to natural weathering indicate no detectable degradation in collector performance and no visable deterioration in appearance of collector. Supporting data and pretest/post test efficiency comparison are included.

  4. Evaluation of high performance evacuated tubular collectors in a residential heating and cooling system: Colorado State University Solar House I. Report for October 1, 1976--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Duff, W.S.; Conway, T.M.; Loef, G.O.G.; Meredith, D.B.; Pratt, R.B.

    1978-03-01

    CSU Solar House I is configured with a prototype Corning evacuated tubular collector and a new Arkla lithium bromide water chiller designed for solar operation. Data have been collected for this configuration since January 1977. Prior to that time and since mid-1974, Solar House I has operated with a flat-plate collector and a previous Arkla LiBr air conditioner modified to operate in the lower solar temperature ranges. Project objectives were to develop an operating and control system for the new configuration and to compare the performance of the new residential solar heating, cooling, and hot water system with performance of the previous system. Many problems were encountered in the evolution of the operating and control systems due to the different operating characteristics of evacuated tubular collectors, such as their rapid thermal response and the possibility of much higher temperatures as compared to a flat-plate collector.

  5. The charged particle accelerators subsystems modeling

    Science.gov (United States)

    Averyanov, G. P.; Kobylyatskiy, A. V.

    2017-01-01

    Presented web-based resource for information support the engineering, science and education in Electrophysics, containing web-based tools for simulation subsystems charged particle accelerators. Formulated the development motivation of Web-Environment for Virtual Electrophysical Laboratories. Analyzes the trends of designs the dynamic web-environments for supporting of scientific research and E-learning, within the framework of Open Education concept.

  6. Report on the ICES subsystem FLOWS

    NARCIS (Netherlands)

    Booij, N.

    1980-01-01

    FLOWS is a recently developed ICES subsystem for applications in the field of hydraulic engineering. It is able to compute steady as well as unsteady flows in hydraulic networks of given dimensions. This means that is does not optimize any parameters describing the network. The network may be compos

  7. Integrating the autonomous subsystems management process

    Science.gov (United States)

    Ashworth, Barry R.

    1992-01-01

    Ways in which the ranking of the Space Station Module Power Management and Distribution testbed may be achieved and an individual subsystem's internal priorities may be managed within the complete system are examined. The application of these results in the integration and performance leveling of the autonomously managed system is discussed.

  8. Spectroscopic subsystems in nearby wide binaries

    CERN Document Server

    Tokovinin, Andrei

    2015-01-01

    Radial velocity (RV) monitoring of solar-type visual binaries has been conducted at the CTIO/SMARTS 1.5-m telescope to study short-period systems. Data reduction is described, mean and individual RVs of 163 observed objects are given. New spectroscopic binaries are discovered or suspected in 17 objects, for some of them orbital periods could be determined. Subsystems are efficiently detected even in a single observation by double lines and/or by the RV difference between the components of visual binaries. The potential of this detection technique is quantified by simulation and used for statistical assessment of 96 wide binaries within 67pc. It is found that 43 binaries contain at least one subsystem and the occurrence of subsystems is equally probable in either primary or secondary components. The frequency of subsystems and their periods match the simple prescription proposed by the author (2014, AJ, 147, 87). The remaining 53 simple wide binaries with a median projected separation of 1300AU have the distri...

  9. 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

  10. A Long Term Test of Differently Designed Evacuated Tubular Collectors

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2008-01-01

    carried out with different mean solar collector fluid temperatures and in different seasons of the year. The results of the measurements are presented in this paper. The influence of the mean solar collector fluid temperature on the thermal performance of the different collector designs will be discussed......During three years seven differently designed evacuated tubular collectors (ETCs) utilizing solar radiation from all directions have been investigated experimentally. The evacuated tubular solar collectors investigated include one SLL all-glass ETC from Tshinghua Solar Co. Ltd, four heat pipe ETCs...... of the inlet fluid to the collectors have been the same for all collectors. The volume flow rate through each of the collectors is adjusted so that the mean solar collector fluid temperature has been the same for all collectors. Thus a direct performance comparison is possible. The side-by-side tests were...

  11. Collector/Receiver Characterization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.

  12. Concentrating solar collector-performance tests

    Science.gov (United States)

    1979-01-01

    Report summarizes test results from evaluation of concentrating solar collector thermal performance, from transient behavior, and incident-of-angle behavior. Tests were conducted using National Bureau of Standards recommedations and specifications.

  13. Processing on high efficiency solar collector coatings

    Science.gov (United States)

    Roberts, M.

    1977-01-01

    Wavelength selective coatings for solar collectors are considered. Substrates with good infrared reflectivity were examined along with their susceptibility to physical and environmental damage. Improvements of reflective surfaces were accomplished through buffing, chemical polishing and other surface processing methods.

  14. Performance of a solar-thermal collector

    Science.gov (United States)

    Higa, W. H.

    1975-01-01

    Possible means of achieving the technology required for field application of solar thermal power systems are discussed. Simplifications in construction techniques as well as in measurement techniques for parabolic trough collectors are described. Actual measurement data is also given.

  15. The Digital Electronic Subsystem of Marsis

    Science.gov (United States)

    Maltecca, L.; Pecora, M.; Scandelli, L.

    MARSIS (Mars Advanced Radar for Subsurface and Ionospheric Sounding) is one of the Instrument of the ESA Mars Express mission, to be launched in June 2003 with a Soyuz/Fregate. Its primary objective is to map the distribution of water, both liquid and solid, in the upper portions of the crust of Mars. Secondary objectives are subsurface geologic probing, surface characterisation and ionosphere sounding. The MARSIS instrument is a low-frequency nadir-looking pulse limited radar sounder and altimeter with ground penetration capabilities, which uses synthetic aperture techniques and a secondary-receiving antenna to isolate subsurface reflections. Functionally and also from the responsibility point of view of each organisation involved in MARSIS, the instrument can be split into three subsystems: - Antenna: ANT - Radio Frequency Subsystem: RFS (TX+RX) - Digital Electronics Subsystem: DES MARSIS is an international co-operation between Italian Space Agency (ASI) and National Aeronautics and Space Administration (NASA). The experiment has an Italian Principal investigator (from Infocom Dept. of University of Rome "La Sapienza"), an U.S. Co-PI (from Jet Propulsion Laboratory), and Co-I~@~Ys from Italy, the U.S. and other countries. Italy is the lead for the experiment definition with the participation of the U.S.. In particular Alenia Spazio/Rome is the Prime Contractor of the industrial team and also supplier of part of the RF subsystem. Laben (a company of Finmeccanica) is the supplier of the Digital Electronic Subsystem (DES), including its basic and application SW, as subcontractor of ALS. The purpose of this paper is to describe the DES from HW and SW point of view, including the Test Equipment and the special simulator developed used for DES validation.

  16. 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...... correctness of Cheney’s copying garbage collector in our program logic. Finally, we prove that our implementation of Cheney’s algorithm meets its specification using the logic we have given and auxiliary variables. Udgivelsesdato: 2008...

  17. Effects of High Temperature on Collector Coatings

    Science.gov (United States)

    Lowery, J. R.

    1982-01-01

    Report reveals electroplated black chrome is good coating for concentrating collectors in which temperatures are in the 650 degrees-800 degrees F (340 degrees - 430 degrees C) range. Black chrome thermal emittance is low and solar-absorption properties are not seriously degraded at high temperatures. Black coatings are used to increase absorption of solar energy by base metal while decreasing emission of infrared energy. Coatings are intended to improve efficiency of solar collectors.

  18. Developments of solar collectors in China

    Institute of Scientific and Technical Information of China (English)

    Yin Zhiqiang

    2009-01-01

    China has abundant solar energy resource. Solar thermal collectors, particularly all-glass evacuated tubular collectors, have been studied and developed for 30 years, and solar thermal industry has developed rapidly for 15 years. There are various solar thermal systems, with an operation area of around 108 million m2 in 2007. These systems mainly provide domestic hot water, but some other applications are under extensive study and development as well.

  19. Simulation Application for Optimization of Solar Collector Array

    OpenAIRE

    Igor Shesho*,; Done Tashevsk

    2014-01-01

    Solar systems offer a comparatively low output density , so increasing the output always means a corresponding increase in the size of the collector area. Thus collector arrays are occasionally constructed (i.e. with different azimuth angles and/or slopes, which be imposed by the location and structure available to mount the collector. In this paper is developed simulation application for optimization for the solar collector array position and number of collectors in regard of...

  20. 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

  1. 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.

  2. Collector sealants and breathing. Mid-term report, September 25, 1978-May 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-01-01

    The objectives of this program are: (1) to investigate the pertinent properties of a variety of possible sealants for solar collectors and identify the most promising candidates and to study the effect of breathing in flat-plate, thermal solar collector units. The study involves two types of sealants, Class PS which includes performed seals or gaskets and Class SC which includes sealing compounds or caulks. It is 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 are being augmented by experimental measurements. Environmental stresses to be evaluated by these measuremets include elevated temperatures, moisture, ultraviolet light, ozone and oxygen, and fungus. The second major area of the work involves 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 is being made in order to provide means to mitigate the deleterious effects of water on collector life.Absorbents for organic degradation products of sealants are also being investigated in order to protect the glazing and absorber plate from deposited coatings. Since adsorbents and desiccants in general tend to take up both waer and organic decomposition products, relative affinities of a number of these agents for water and for organic compounds are being determined.

  3. Heat Loss Calculation of Compound Honeycomb Solar Collector

    Institute of Scientific and Technical Information of China (English)

    X.S.Ge; Y.Z.Zhang; 等

    1993-01-01

    A simplified technique is described for calculating the heat loss coefficient from the absorber of the solar flat-plate collector with a combined honeycomb.The problem is treated in two ways:the coupled mode and the decoupled mode.In the analysis,the cell wall and glass cover are assumed to be specularly reflecting and diffusely emitting surfaces,while the absorber is a diffusely reflecting and emitting surface.The influences of emissivities of the absorber and the cell wall as wall as well as the aspect ratio on the heat loss coefficient are predicted.The theoretical results are compared with experimental data reported in the literature,and the agreement is good.

  4. Experimental evaluation of a fixed collector employing vee-trough concentrator and vacuum tube receivers

    Science.gov (United States)

    Selcuk, M. K.

    1977-01-01

    A test bed for experimental evaluation of a fixed solar collector which combines an evacuated glass tube solar receiver with a flat plate/black chrome plated copper absorber and an asymmetric vee-trough concentrator was designed and constructed. Earlier predictions of thermal performance were compared with test data acquired for a bare vacuum tube receiver; and receiver tubes with Alzak aluminum, aluminized FEP Teflon film laminated sheet metal and second surface ordinary mirror reflectors. Test results and system economics as well as objectives of an ongoing program to obtain long-term performance data are discussed.

  5. Partitioning a macroscopic system into independent subsystems

    Science.gov (United States)

    Delle Site, Luigi; Ciccotti, Giovanni; Hartmann, Carsten

    2017-08-01

    We discuss the problem of partitioning a macroscopic system into a collection of independent subsystems. The partitioning of a system into replica-like subsystems is nowadays a subject of major interest in several fields of theoretical and applied physics. The thermodynamic approach currently favoured by practitioners is based on a phenomenological definition of an interface energy associated with the partition, due to a lack of easily computable expressions for a microscopic (i.e. particle-based) interface energy. In this article, we outline a general approach to derive sharp and computable bounds for the interface free energy in terms of microscopic statistical quantities. We discuss potential applications in nanothermodynamics and outline possible future directions.

  6. Controls Interfaces for Two ALICE Subsystems

    Science.gov (United States)

    Thomen, Robert

    2007-10-01

    Software for the control of a laser alignment system for the Inner Tacking System (ITS) and for the Electromagnetic Calorimeter (EMC) was developed for the ALICE (A Large Ion Collider Experiment) at CERN. The interfaces for both subsystems use the CERN-standard hardware controls system PVSS (Prozessvisualisierungs- und Steuerungs-System). Software for the ITS has been created to measure the relative alignment of the ITS with the Time Projection Chamber (TPC) so to ensure accurate particle tracking. The ITS alignment system locates laser images in four cameras. The EMC requires several subsystems to be running in order to operate properly. Software has been created and tested for the detector's high and low voltage systems, and temperature monitoring hardware. The ITS and EMC software specifications and design requirements are presented and their performance is analyzed.

  7. Analysis of the human operator subsystems

    Science.gov (United States)

    Jones, Lynette A.; Hunter, Ian W.

    1991-01-01

    Except in low-bandwidth systems, knowledge of the human operator transfer function is essential for high-performance telerobotic systems. This information has usually been derived from detailed analyses of tracking performance, in which the human operator is considered as a complete system rather than as a summation of a number of subsystems, each of which influences the operator's output. Studies of one of these subsystems, the limb mechanics system, demonstrate that large parameter variations can occur that can have a profound effect on the stability of force-reflecting telerobot systems. An objective of this research was to decompose the performance of the human operator system in order to establish how the dynamics of each of the elements influence the operator's responses.

  8. New method for energy prediction of solar energy collectors systems in Yemen

    Energy Technology Data Exchange (ETDEWEB)

    Almakaleh, Abdo A. [Univ. of Science and Technology, Solar Energy Center, Sana' a (Yemen)

    2008-07-01

    The design of any solar system will require the full understanding of the most influenced factors on its power generation and performance year round. Therefore, one has to consider the system components variables, namely collector types, tilts and collectors orientations to capture most of the incoming solar radiation. Direct measurements of global solar radiation do exist for a number of sites around the country for many years and can be used to derive a set of equations to predict the solar system design values and its output performance. But, the solar system power output, whether it's electric or thermal energy can be very difficult to predict in the absence of measured data and variable load's demand requirements. This paper examines the effects of solar radiation in each site on the systems power output of PV and thermal energy for different type of collectors. Using the existing data from meteorological stations to derive an accurate and simple equations with only one input variable, the monthly average clearness index to be used for the design of photovoltaic and solar thermal system power outputs for tilted flat plate, polar and two axis tracking collectors for a given site instead of existing lengthy methods of solar radiation components (direct, diffuse, and reflected radiation) for different types of collectors currently in use or computer simulations programs. The results of the new equations provide a valuable tool for solar collector designer and prediction method for the systems power outputs. Furthermore, the new equations indicate the possibility of universal applications with minimum adjustment for latitude. (orig.)

  9. 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.

  10. Sener Parabolic trough Collector Design and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda, N.; Vazquez, J.; Domingo, M.

    2006-07-01

    Parabolic trough technology is nowadays the most extended solar system for electricity production or steam generation for industrial processes. It is basically composed of a collector field which converts solar irradiation into thermal energy- and a conventional thermal-toelectric conversion Rankine cycle. In these plants, a storage system can be implemented in order to increase plant production. Collector field represents more than half the total plant cost. Therefore, SENER has made an effort to improve current state of the art of parabolic trough collector (PTC from now on) design in order to reduce plant costs. Main characteristic of SENER design lies on the use of a torque tube as the central body of the collector. This tube is made of steel sheet, with a thickness depending on wind load requirements on the collector. This concept is very cost-effective, since the man-power needed to manufacture the tube has been minimized. Continuous cylindrical shape of the torque tube provides a high torsional stiffness, which is one of the main parameters affecting collector optical efficiency. Cantilever arms connect the mirrors to the central torque tube. These components are usually made of welded tube profiles. In SENER's new design, these cantilever arms are made using metal sheet stamping techniques (SENER patent), thus reducing manufacturing and mounting costs. SENER PTC module (called SENERTROUGH) is 12 meters long and has an aperture width of 5,76 m. HCE and curved mirrors existing in the market - as well as new products from different manufacturers - can be easily attached to collector structure. Two prototype modules of SENERTROUGH have been mounted and tested at the CIEMAT-PSA facilities. Several performance tests were performed in order to assure the validity of the concept. (Author)

  11. Optical Subsystems for Next Generation Access Networks

    DEFF Research Database (Denmark)

    Lazaro, J.A; Polo, V.; Schrenk, B.

    2011-01-01

    Recent optical technologies are providing higher flexibility to next generation access networks: on the one hand, providing progressive FTTx and specifically FTTH deployment, progressively shortening the copper access network; on the other hand, also opening fixed-mobile convergence solutions...... in next generation PON architectures. It is provided an overview of the optical subsystems developed for the implementation of the proposed NG-Access Networks....

  12. Liquid radioactive waste subsystem design description

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-06-01

    The Liquid Radioactive Waste Subsystem provides a reliable system to safely control liquid waste radiation and to collect, process, and dispose of all radioactive liquid waste without impairing plant operation. Liquid waste is stored in radwaste receiver tanks and is processed through demineralizers and temporarily stored in test tanks prior to sampling and discharge. Radwastes unsuitable for discharge are transferred to the Solid Radwaste System.

  13. Optical Subsystems for Next Generation Access Networks

    DEFF Research Database (Denmark)

    Lazaro, J.A; Polo, V.; Schrenk, B.

    2011-01-01

    Recent optical technologies are providing higher flexibility to next generation access networks: on the one hand, providing progressive FTTx and specifically FTTH deployment, progressively shortening the copper access network; on the other hand, also opening fixed-mobile convergence solutions...... in next generation PON architectures. It is provided an overview of the optical subsystems developed for the implementation of the proposed NG-Access Networks....

  14. Evaluation of Test Method for Solar Collector Efficiency

    DEFF Research Database (Denmark)

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

    /S. The solar collector panel investigated has 16 parallel connected horizontal absorber fins. CFD (Computational Fluid Dynamics) simulations, calculations with a solar collector simulation program SOLEFF (Rasmussen and Svendsen, 1996) and thermal experiments are carried out in the investigation......The test method of the standard EN12975-2 (European Committee for Standardization, 2004) is used by European test laboratories to determine the efficiency of solar collectors. In the test methods the mean solar collector fluid temperature in the solar collector, Tm is determined by the approximated...... equation where Tin is the inlet temperature to the collector and Tout is the outlet temperature from the collector. The specific heat of the solar collector fluid is in the test method as an approximation determined as a constant equal to the specific heat of the solar collector fluid at the temperature Tm...

  15. Subsystem codes with spatially local generators

    CERN Document Server

    Bravyi, Sergey

    2010-01-01

    We study subsystem codes whose gauge group has local generators in the 2D geometry. It is shown that there exists a family of such codes defined on lattices of size LxL with the number of logical qubits k and the minimum distance d both proportional to L. The gauge group of these codes involves only two-qubit generators of type XX and ZZ coupling nearest neighbor qubits (and some auxiliary one-qubit generators). Our proof is not constructive as it relies on a certain version of the Gilbert-Varshamov bound for classical codes. Along the way we introduce and study properties of generalized Bacon-Shor codes which might be of independent interest. Secondly, we prove that any 2D subsystem [n,k,d] code with spatially local generators obeys upper bounds kd=O(n) and d^2=O(n). The analogous upper bound proved recently for 2D stabilizer codes is kd^2=O(n). Our results thus demonstrate that subsystem codes can be more powerful than stabilizer codes under the spatial locality constraint.

  16. Singularly perturbed bifurcation subsystem and its application in power systems

    Institute of Scientific and Technical Information of China (English)

    An Yichun; Zhang Qingling; Zhu Yukun; Zhang Yan

    2008-01-01

    The singularly perturbed bifurcation subsystem is described,and the test conditions of subsystem persistence are deduced.By use of fast and slow reduced subsystem model,the result does not require performing nonlinear transformation.Moreover,it is shown and proved that the persistence of the periodic orbits for Hopf bifurcation in the reduced model through center manifold.Van der Pol oscillator circuit is given to illustrate the persistence of bifurcation subsystems with the full dynamic system.

  17. Optical and thermal testing of convection reduction mechanisms in a new 1.2X CPC solar collector

    Science.gov (United States)

    Carvalho, Maria J.; Collares-Pereira, Manuel; de Oliveira, Joao C.; Mendes, Joao F.; Haeberle, A.; Wittwer, Volker

    1994-09-01

    A new non-evacuated solar collector of the CPC type, developed and manufactured in Portugal, is now commercially available. Its design features are unique and deserve a careful study, both of its optical and of its thermal characteristics. The optics is interesting given the unusual shape and the opportunity to test different convection suppression schemes and determine their impacts on the collector's optical performance. As for the collector's thermal behavior it is very interesting to test how simple (and potential marketable) different convection suppression ideas can improve an already very good collector from the heat loss point of view (FUL equals 4.0 W/( degree(s)C.m2)). In the course of the paper a brief description of the collector is given and testing results are presented for the testing carried out in the following situations: (1) (i) measurement of its optical and thermal performance (instantaneous efficiency curve) measured both in E.W. and N.S. collector orientation (the collector has a very wide acceptance angle allowing it to work in N.S. orientation and, thus, function in a thermosyphon mode like any regular flat plate collector, (ii) measurement of its angular acceptance function; (2) measurement of the instantaneous efficiency curve after the introduction of (i) a thin Teflon high transmissivity film below the glass cover, (ii) transparent insulation of the capillary type, inserted also under the glass cover, (iii) measurement of the acceptance angle function in this last situation. In this paper it is shown that the addition of the film reduces the heat loss coefficient by a factor of 1.3 W/( degree(s)C.m2) and the transparent insulation leads only to an improvement of 1.0 W/( degree(s)C.m2) in that same coefficient.

  18. Thermal energy storage subsystems (a collection of quarterly reports)

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    Five quarterly reports are presented, covering the progress made in the development, fabrication, and delivery of three Thermal Energy Storage Subsystems. The design, development, and progress toward the delivery of three subsystems are discussed. The subsystem uses a salt hydrate mixture for thermal energy storage. Included are the program schedules, technical data, and other program activities from October 1, 1976 through December 31, 1977.

  19. The determination of space parameters of the heliostatic collector field

    Directory of Open Access Journals (Sweden)

    Dušan Kudelas

    2006-04-01

    Full Text Available The assurance of perpetual perpendicular insolation of solar collector absorber surface may increase the insolation energy byca 42-45 %.. A consequence of theincrease in the energy production may be the reduction of the solar collectors’ surface area. For the large scale solar collector field conception is advantageous to build collector sections with several collectors in one heliostat. For the conception of the solar collector field with heliostat collectors is important to make a regular identification of space parameters of all parts of the solar system field. The placement of the heliostats is a basic condition for the optimal insolation conditions of heliostat solar collectors’ field.

  20. Corrosion test cell for bipolar plates

    Science.gov (United States)

    Weisbrod, Kirk R.

    2002-01-01

    A corrosion test cell for evaluating corrosion resistance in fuel cell bipolar plates is described. The cell has a transparent or translucent cell body having a pair of identical cell body members that seal against opposite sides of a bipolar plate. The cell includes an anode chamber and an cathode chamber, each on opposite sides of the plate. Each chamber contains a pair of mesh platinum current collectors and a catalyst layer pressed between current collectors and the plate. Each chamber is filled with an electrolyte solution that is replenished with fluid from a much larger electrolyte reservoir. The cell includes gas inlets to each chamber for hydrogen gas and air. As the gases flow into a chamber, they pass along the platinum mesh, through the catalyst layer, and to the bipolar plate. The gas exits the chamber through passageways that provide fluid communication between the anode and cathode chambers and the reservoir, and exits the test cell through an exit port in the reservoir. The flow of gas into the cell produces a constant flow of fresh electrolyte into each chamber. Openings in each cell body is member allow electrodes to enter the cell body and contact the electrolyte in the reservoir therein. During operation, while hydrogen gas is passed into one chamber and air into the other chamber, the cell resistance is measured, which is used to evaluate the corrosion properties of the bipolar plate.

  1. Thermal performance of solar air collector with transparent honeycomb made of glass tube

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Transparent honeycomb structure with thin-walled glass tube as the honeycomb unit is designed and applied to a flat-plate solar air collector. Experiments are performed for solar collectors with six different honeycomb sizes. The emphasis is to study the effects of diameter and aspect ratio of the honeycomb unit on the transmittance and efficiency of the solar collector. It is shown that for the same diameter but different aspect ratios, there are large temperature differences between the collector’s exits; the smaller the aspect ratio, the larger the exit temperature, with a maximum difference of 10℃; for the same aspect ratio but different diameters, the temperature differences are small; the maximum temperature difference between the collectors with and without honeycombs is 12℃. A theoretical expression for the honeycomb transmittance is derived with a simplified method. The result shows that the honeycomb transmittance is only related with the aspect ratio and the materials’ optical properties but not the actual size of the honeycomb.

  2. 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.

  3. Design and Development of Prototype Cylindrical Parabolic Solar Collector for Water Heating Application

    Directory of Open Access Journals (Sweden)

    Hrushikesh Bhujangrao Kulkarni

    2016-02-01

    Full Text Available Concentrating collectors absorbs solar energy and convert it into heat for generating hot water, steam at required temperature, which can be further used for solar thermal applications. The developing countries like India where solar energy is abundantly available; there is need to develop technology for harnessing solar energy for power production, but the main problem associated with concentrating solar power technology is the high cost of installation and low output efficiency. To solve this problem, a prototype cylindrical parabolic solar collector having aperture area of 1.89 m2 is designed and developed using low cost highly reflecting and absorbing material to reduce initial cost of project and improve thermal efficiency. ASHRAE Standard 93, 1986 was used to evaluate the thermal performance and it was observed that this system can generate hot water at an average temperature of 500C per day with an average efficiency of 49% which is considerable higher than flat plate solar collectors. Hot water produced by this system can be useful for domestic, agricultural, industrial process heat applications.Article History: Received Sept 19, 2015; Received in revised form Dec 23, 2015; Accepted February 2, 2016; Available online How to Cite This Article: Bhujangrao, K.H. (2016. Design and Development of Prototype Cylindrical Parabolic Solar Collector for Water Heating Application. International Journal of Renewable Energy Development, 5(1, 49-55 http://dx.doi.org/10.14710/ijred.5.1.49-55 

  4. Effect of operating temperature on the HWB model for solar-collector design

    Science.gov (United States)

    Huang, H.; Howell, J. R.

    1983-02-01

    The Hottel-Whillier-Bliss (HWB) Model for the thermal efficiency of a flat plate solar collector plots as a straight line in an esa/sub c/ approx. (T/sub f,in/ - T/sub a/)/g/sub s/ coordinate system under the following assumptions: (1) the effect of the thermal capacity in the collector is negligible; (2) F/sub R/, U/sub L/ are constant in the range of operating temperature. These assumptions simplify the model and make it convenient to use. Because of the intermittance of insulation and the variation of ambient temperature and wind speed, the thermal capacity of the collector may affect the transient efficiency of the collector. In addition, the values of F/sub R/ and U/sub L/ are actually not constant and cause deviation of the efficiency curve from a straight line. The concern is with the deviation of the confidence level for a specific operating range. The effect of operating temperature of the values of F/sub R/ and U/sub L/ is discussed.

  5. Materials for luminescent greenhouse solar collectors.

    Science.gov (United States)

    Levitt, J A; Weber, W H

    1977-10-01

    Luminescent greenhouse solar collectors are potentially useful for concentrating sunlight onto photovoltaic power cells. Measurements of the performance of small-scale collectors made of two commercially available materials (Owens-Illinois ED2 neodymium-doped laser glass and rhodamine 6G-doped plastic) are presented. The results are encouraging, but they indicate a need for further spectral sensitization and for reduced matrix loss coefficient. The measurements with monochromatic illumination agree with the predictions of a mathematical model developed to take account of reemission following the absorption of luminescence. Under solar illumination, the model predicts photon flux concentrations of about 15 for optimized full-scale collectors made of the materials studied and concentrations of 110 for reasonably improved glass.

  6. Optimum solar collector fluid flow rates

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    1996-01-01

    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...... to the temperature difference between the solar collector and the bottom of the mantle - an increase of about 1% of the thermal performance is possible.Finally, calculations showed that the highest thermal performance for large SDHW systems with constant volume flow rates in the solar collector loops are achieved....... 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...

  7. Space-reactor electric systems: subsystem technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.V.; Bost, D.; Determan, W.R.

    1983-03-29

    This report documents the subsystem technology assessment. For the purpose of this report, five subsystems were defined for a space reactor electric system, and the report is organized around these subsystems: reactor; shielding; primary heat transport; power conversion and processing; and heat rejection. The purpose of the assessment was to determine the current technology status and the technology potentials for different types of the five subsystems. The cost and schedule needed to develop these potentials were estimated, and sets of development-compatible subsystems were identified.

  8. Projection of distributed-collector solar-thermal electric power plant economics to years 1990-2000

    Science.gov (United States)

    Fujita, T.; Elgabalawi, N.; Herrera, G.; Turner, R. H.

    1977-01-01

    A preliminary comparative evaluation of distributed-collector solar thermal power plants was undertaken by projecting power plant economics of selected systems to the 1990 to 2000 time frame. The selected systems include: (1) fixed orientation collectors with concentrating reflectors and vacuum tube absorbers, (2) one axis tracking linear concentrator including parabolic trough and variable slat designs, and (3) two axis tracking parabolic dish systems including concepts with small heat engine-electric generator assemblies at each focal point as well as approaches having steam generators at the focal point with pipeline collection to a central power conversion unit. Comparisons are presented primarily in terms of energy cost and capital cost over a wide range of operating load factors. Sensitvity of energy costs for a range of efficiency and cost of major subsystems/components is presented to delineate critical technological development needs.

  9. 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....

  10. Optical fiber telecommunications components and subsystems

    CERN Document Server

    Kaminow, Ivan; Willner, Alan E

    2013-01-01

    Optical Fiber Telecommunications VI (A&B) is the sixth in a series that has chronicled the progress in the R&D of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition brings a fresh look to many essential topics, including devices, subsystems, systems and networks. A central theme is the enabling of high-bandwidth communications in a cost-effective manner for the development of customer applications. These volumes are an ideal reference for R&D engineers and managers, optical systems implementers, university researchers and s

  11. Global GEO survey subsystem of the ISON

    Science.gov (United States)

    Molotov, Igor; Agapov, Vladimir; Rumyantsev, Vasiliy; Biryukov, Vadim; Kornienko, Gennadiy; Litvinenko, Elena; Vikhristenko, Alexander; Zalles, Rodolfo; Guseva, Irina; Inasaridze, Raguli

    Dedicated subsystem of the International Scientific Optical Network (ISON) is created in order to provide the regular monitoring of the objects brighter than 15m at GEO region. For GEO longitudes between 31.5W and 90E a survey mode is implemented in a zone of ±16° width with respect to equator, for longitudes between 90E and 210W the selective areas are surveyed regularly in a zone of ±10° width, and for longitudes between 135W and 1 E the periodic observations are arranged in a zone of ±1° width. Initially existing astrographs of 23 cm and 40 cm aperture with FOV of 30'x30' were involved into the work. Then the dedicated 22-cm aperture telescope installed on the automated mount was elaborated. This new telescope having FOV of 4° x4° can provide up to 5000 measurements for around 400 GEO and HEO (mainly GTO) objects per night. Currently the six similar 22-cm aperture telescopes at different stages of operations are working in Tiraspol (Pridnestrovie), Nauchniy (Crimea, Ukraine), Pulkovo (St.-Petersburg, Russia), Kitab (Uzbekistan) and Ussuriysk (Far East, Russia) observation facilities. During the year of 2008 similar telescopes will be installed in Abastumani (Georgia), Milkovo (Kamchatka, Russia), Tarija (Bolivia), Blagoveshchensk (Far East, Russia) and Gissar (Tadjikistan). Since 2009 the subsystem will provide surveying capability for the GEO region in global scale both by longitude (0° -360° ) and inclination (0° -20° ). The trial operations of the first fully automated 22-cm telescope during 2007 (the part of GEO arc between 31.5W and 90E was surveyed about 60 times) showed existing large gap in our knowledge of space debris populations at GEO region. Few hundreds of uncatalogued respectively bright objects are detected at GEO and GTO orbits. Special processing of obtained short arc tracks for non-correlated object allowed to correlate some of them and thus to discover around 40 new objects. During 2007 slightly less than 200000 measurements

  12. Subsystem's dynamics under random Hamiltonian evolution

    CERN Document Server

    Vinayak,

    2011-01-01

    We study time evolution of a subsystem's density matrix under a unitary evolution, generated by a sufficiently complex, say quantum chaotic, Hamiltonian. We exactly calculate all coherences, purity and fluctuations. The reduced density matrix is described in terms of a noncentral correlated Wishart ensemble. Our description accounts for a transition from an arbitrary initial state towards a random state at large times, enabling us to determine the convergence time after which random states are reached. We identify and describe a number of other interesting features, like a series of collisions between the largest eigenvalue and the bulk, accompanied by a phase transition in its distribution function.

  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. 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....

  15. Solar Air Collectors: How Much Can You Save?

    Science.gov (United States)

    Newburn, J. D.

    1985-04-01

    A collector efficiency curve is used to determine the output of solar air collectors based on the testing of seven solar collectors sold in Iowa. In this application the solar heater is being used as a space heater for a house. The performance of the solar air heater was analyzed and an 8% savings in energy was achieved over a one year period using two 4 x 8 collectors in a typical house.

  16. Experimental investigation of efficiency of a novel conical solar collector

    OpenAIRE

    MORAVEJ, M

    2015-01-01

    One of the methods to improvement of solar-to-thermal energy conversion is the design of geometry in solar collectors. In this paper, the new solar collector which is called solar conical collector has been designed and tested. The efficiency of solar conical collector was experimentally investigated by use of ASHRAE standard. Experiments were performed with water as a working fluid in the outdoor condition of Ahvaz city in the south of Iran. The results show that the average efficiency of a ...

  17. A comparison between the solar energy collection by fix and tracking collectors

    Energy Technology Data Exchange (ETDEWEB)

    Garrison, John D [San Diego State University, San Diego (United States)

    2000-07-01

    A realistic mathematical simulation of solar thermal energy collection for an air flat plate collector, six designs of fixed evacuated collectors and two designs of tracking evacuated collectors at port Hardy, British Columbia and Edmonton, Alberta, in Canada and Daggett, California in the United States has been calculated. Differences in solar energy collection by the different collector designs arise only from differences in collector geometry, since the same collector orientations, selective absorber and solar radiation data are used in the simulations for all collector designs. It is found that solar energy collection in Canada by an air flat plate collector is significantly lower than that of the fixed evacuated and the tracking evacuated collectors at the lowest operating temperatures. This occurs because of the high thermal losses for the air flat plate collector, and the low solar insolation and low winter ambient temperatures in Canada. Highly concentrating tracking collectors which collect no diffuse radiation do not collect as much solar energy at lower temperatures as all of the fixed evacuated collectors at Port Hardy in Canada where there are a limited number of clear days. The fixed, vacuum tubular (dewar type) collector collects the most solar energy at low temperatures. At higher temperatures it collects the least amount of energy of all of the evacuated collectors. This is because of its low concentration and thus larger radiation losses. The vacuum vertical fin and higher concentration shaped glass evacuated collectors at high temperatures. Solar energy collection at Daggett is much higher than that at the two Canadian stations because of the high solar insolation and moderate to warm ambient temperatures. By rotating of the more highly concentrating CPC evacuated collectors about their axes placed parallel to the polar axis so as to track the sun, significantly higher energy collection is obtained, particularly for sites with higher annual

  18. Cascade impactor and jet plate for same

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Robert S.; Farthing, William E.; Landham Jr., Edward C.

    2004-02-03

    A sampling system and method for sampling particulate matter from a high-temperature, high-pressure gas stream. A cyclone sampler for use at high temperatures and pressures, and having threadless sacrificial connectors is disclosed. Also disclosed is an improved cascade impactor including jet plates with integral spacers, and alignment features provided for aligning the jet plates with their associated collection substrates. An activated bauxite alkali collector is disclosed, and includes an alumina liner. The sampling system can be operated remotely or locally, and can be permanently installed or configured as a portable system.

  19. Solar collector design with respect to moisture problems

    DEFF Research Database (Denmark)

    Holck, Ole; Svendsen, Svend; Brunold, Stefan

    2003-01-01

    Humidity inside the collectors is one factor that can be minimised to keep the most favourable microclimatic condition for the internal materials of the collector. This microclimate inside the collector is an important factor in determining the service lifetime of an absorber coating. During the ...

  20. UGV: security analysis of subsystem control network

    Science.gov (United States)

    Abbott-McCune, Sam; Kobezak, Philip; Tront, Joseph; Marchany, Randy; Wicks, Al

    2013-05-01

    Unmanned Ground vehicles (UGVs) are becoming prolific in the heterogeneous superset of robotic platforms. The sensors which provide odometry, localization, perception, and vehicle diagnostics are fused to give the robotic platform a sense of the environment it is traversing. The automotive industry CAN bus has dominated the industry due to the fault tolerance and the message structure allowing high priority messages to reach the desired node in a real time environment. UGVs are being researched and produced at an accelerated rate to preform arduous, repetitive, and dangerous missions that are associated with a military action in a protracted conflict. The technology and applications of the research will inevitably be turned into dual-use platforms to aid civil agencies in the performance of their various operations. Our motivation is security of the holistic system; however as subsystems are outsourced in the design, the overall security of the system may be diminished. We will focus on the CAN bus topology and the vulnerabilities introduced in UGVs and recognizable security vulnerabilities that are inherent in the communications architecture. We will show how data can be extracted from an add-on CAN bus that can be customized to monitor subsystems. The information can be altered or spoofed to force the vehicle to exhibit unwanted actions or render the UGV unusable for the designed mission. The military relies heavily on technology to maintain information dominance, and the security of the information introduced onto the network by UGVs must be safeguarded from vulnerabilities that can be exploited.

  1. Force protection demining system (FPDS) detection subsystem

    Science.gov (United States)

    Zachery, Karen N.; Schultz, Gregory M.; Collins, Leslie M.

    2005-06-01

    This study describes the U.S. Army Force Protection Demining System (FPDS); a remotely-operated, multisensor platform developed for reliable detection and neutralization of both anti-tank and anti-personnel landmines. The ongoing development of the prototype multisensor detection subsystem is presented, which integrates an advanced electromagnetic pulsed-induction array and ground penetrating synthetic aperture radar array on a single standoff platform. The FPDS detection subsystem is mounted on a robotic rubber-tracked vehicle and incorporates an accurate and precise navigation/positioning module making it well suited for operation in varied and irregular terrains. Detection sensors are optimally configured to minimize interference without loss in sensitivity or performance. Mine lane test data acquired from the prototype sensors are processed to extract signal- and image-based features for automatic target recognition. Preliminary results using optimal feature and classifier selection indicate the potential of the system to achieve high probabilities of detection while minimizing false alarms. The FPDS detection software system also exploits modern multi-sensor data fusion algorithms to provide real-time detection and discrimination information to the user.

  2. Selective optical coatings for solar collectors

    Science.gov (United States)

    Lowery, J. R.

    1980-01-01

    For best performance, energy-absorbing surface of solar collector should be characterized by high ratio of solar absorptance to thermal emitance. Report on optical characteristics of several chemical treatments and electrodeposited coatings for metal solar-absorbing surfaces should interest designers and users of solar-energy systems. Moisture resistance of some coatings is also reported.

  3. Natural-oxide solar-collector coatings

    Science.gov (United States)

    Krupnick, A. C.; Roberts, M. L.; Sharpe, M. H.

    1979-01-01

    Optically selective coatings for solar collectors are produced by thermally treating stainless steel in furnace after series of cleaning and soaking operations. Coatings have withstood 18-month exposure tests at 100 percent relative humidity and temperatures of 95 F. Room temperature coatings are valuable as they are inexpensive to produce, highly production oriented, and environmentally stable.

  4. New tool for standardized collector performance calculations

    DEFF Research Database (Denmark)

    Perers, Bengt; Kovacs, Peter; Olsson, Marcus;

    2011-01-01

    A new tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance for a number of representative cities in Europe...

  5. A test program for solar collectors

    Science.gov (United States)

    1980-01-01

    Rigorous environmental and performance tests qualify solar collector for use in residential solar-energy systems. Testing over 7 month period examined pressurized effects, wind and snow loading, hail damage, solar and thermal degradation, effects of pollutants, efficiency, and outgassing. Test procedures and results are summarized in tables, graphs, and text.

  6. Analysis of Flat-Plate Solar Array and Solar Lantern

    Directory of Open Access Journals (Sweden)

    P. L. N. V. Aashrith

    2014-05-01

    Full Text Available A very detailed theortical analysis of a solar array has been carried out based on established values of solar radiation data to predict the performance of solar lamp . The analysis is based on established theory about flat-plate collectors. Top heat loss coefficient (Ut, Bottom heat loss coefficient (Ub, Overall heat loss coefficient (Ul, Useful energy (Qu, efficiency (hp of the flat-plate solar array and efficiency (hl of the solar lantern has been calculated.

  7. 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

  8. 新型平板太阳能PV/T空气集热器传热特性的数值研究%Numerical Simulation of Thermal Performance of a New Type of Flat-Plate Solar PV/T Air Collector

    Institute of Scientific and Technical Information of China (English)

    孙健; 徐银文; 黄章峰; 李杰

    2015-01-01

    文中设计了一款新型PV/T一体化空气集热器,建立了新型PV/T空气系统内部传热过程的一维非稳态数学模型,并利用差分法对模型进行了数值计算。根据计算结果对一体化系统的性能及影响因素进行了分析。结果表明:在一定的光照强度下,随着空气质量流量增加,电池板温度Tp逐渐下降,空气温升逐渐降低;而热效率、光电转化效率、联合效率随空气流量的增加有所升高。模型的建立为高性能太阳能PV/T一体化空气集热器的优化设计提供较好理论依据。%In this paper, a new type of integrated solar PV/T air collector is designed. A one-dimensional unsteady mathematical model is developed, the internal heat transfer process is calculated by ifnite difference approach. The performance of PV/T solar air collector is predicted under different parameters and conditions. Results indicate that the temperature of solar cell and outlet air decrease with the increase of air mass lfow rate under the same incident solar intensity. Then, the thermal efifciency, electrical efifciency and total efifciency of PV/T system increase with the rising of the inlet air mass lfow rate. The models provide valuable theoretical basis for the optimal design of high-performance solar PV/T integrated air system.

  9. Thermal performance of honeywell double covered liquid solar collector

    Science.gov (United States)

    Losey, R.

    1977-01-01

    The test procedures and results obtained during an evaluation test program to determine the outdoor performance characteristics of the Honeywell liquid solar collector are presented. The program was based on the thermal evaluation of a Honeywell double covered liquid solar collection. Initial plans included the simultaneous testing of a single covered Honeywell collector. During the initial testing, the single covered collector failed due to leakage; thus, testing continued on the double covered collector only. To better define the operating characteristics of the collector, several additional data points were obtained beyond those requested.

  10. Central-Receiver Solar-Thermal Power System 10-MW/sub e/ Pilot Plant: collector subsystem manufacturing plan report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-09-15

    The overall manufacturing planning effort included: design modification analysis; manufacturing/tooling conceptual trades; process/tooling verification experiments; and documentation of manufacturing plans and cost estimates. Innovative tooling concepts were evaluated. Studies also included comparison of costs of both field and shop assembly of heliostats.

  11. HYBRID FUEL CELL-SOLAR CELL SPACE POWER SUBSYSTEM CAPABILITY.

    Science.gov (United States)

    This report outlines the capabilities and limitations of a hybrid solar cell- fuel cell space power subsystem by comparing the proposed hybrid system...to conventional power subsystem devices. The comparisons are based on projected 1968 capability in the areas of primary and secondary battery, fuel ... cell , solar cell, and chemical dynamic power subsystems. The purpose of the investigation was to determine the relative merits of a hybrid power

  12. Local subsystems in gauge theory and gravity

    CERN Document Server

    Donnelly, William

    2016-01-01

    We consider the problem of defining localized subsystems in gauge theory and gravity. Such systems are associated to spacelike hypersurfaces with boundaries and provide the natural setting for studying entanglement entropy of regions of space. We present a general formalism to associate a gauge-invariant classical phase space to a spatial slice with boundary by introducing new degrees of freedom on the boundary. In Yang-Mills theory the new degrees of freedom are a choice of gauge on the boundary, transformations of which are generated by the normal component of the nonabelian electric field. In general relativity the new degrees of freedom are the location of a codimension-2 surface and a choice of conformal normal frame. These degrees of freedom transform under a group of surface symmetries, consisting of diffeomorphisms of the codimension-2 boundary, and position-dependent linear deformations of its normal plane. We find the observables which generate these symmetries, consisting of the conformal normal me...

  13. Development of light metals automotive structural subsystems

    Energy Technology Data Exchange (ETDEWEB)

    Luo, A.A.; Sachdev, A.K. [General Motors Research and Development Center, Warren, MI (United States)

    2007-07-01

    Key technological developments in aluminum and magnesium alloys were reviewed in relation to the manufacturing processes that enable lightweight automotive structural subsystems. Examples included the materials and processes evolution of lightweight body structures, chassis systems, and instrument panel beams. New aluminum and magnesium alloys and manufacturing technologies used to reduce mass and improve performance in vehicle cradle structures were discussed. Hydroforming processes used to enable the use of lightweight aluminum alloy tubes in automotive body structures were also reviewed, in addition to body architectures enabled by different materials and manufacturing processes. The review noted that magnesium instrument panels are now being designed to provide significant performance improvement, reduced vibration, and enhanced crashworthiness in new automobiles. It was concluded that vehicles will incorporate more lightweight materials such as nanocomposites and aluminum and magnesium sheets. 9 refs., 10 figs.

  14. Theoretical study on a solar collector loop during stagnation

    DEFF Research Database (Denmark)

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon;

    2010-01-01

    A mathematical model simulating the stagnation behavior of a pressurized solar collector loop with solar collectors with a good emptying behavior is developed. Based on the pre-pressure of the expansion vessel, the system filling pressure of the solar collector loop and the design of the solar...... collector loop, the mass of the fluid flowing into the pressurized expansion vessel and the pressures at the top part and at the bottom part of the solar collector loop during stagnation for the solar collector loop are calculated. The theoretically calculated results are compared with experimental results....... There is a good agreement between calculations and measurements. The developed simulation model is therefore suitable to determine the behavior of solar collector loops during stagnation....

  15. Theoretical study on a solar collector loop during stagnation

    DEFF Research Database (Denmark)

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon;

    A mathematical model simulating the stagnation behavior of a pressurized solar collector loop with solar collectors with a good emptying behavior is developed. Based on the pre-pressure of the expansion vessel, the system filling pressure of the solar collector loop and the design of the solar...... collector loop, the mass of the fluid flowing into the pressurized expansion vessel and the pressures at the top part and at the bottom part of the solar collector loop during stagnation for the solar collector loop are calculated. The theoretically calculated results are compared with experimental results....... There is a good agreement between calculations and measurements. The developed simulation model is therefore suitable to determine the behavior of solar collector loops during stagnation....

  16. Plant development, auxin, and the subsystem incompleteness theorem.

    Science.gov (United States)

    Niklas, Karl J; Kutschera, Ulrich

    2012-01-01

    Plant morphogenesis (the process whereby form develops) requires signal cross-talking among all levels of organization to coordinate the operation of metabolic and genomic subsystems operating in a larger network of subsystems. Each subsystem can be rendered as a logic circuit supervising the operation of one or more signal-activated system. This approach simplifies complex morphogenetic phenomena and allows for their aggregation into diagrams of progressively larger networks. This technique is illustrated here by rendering two logic circuits and signal-activated subsystems, one for auxin (IAA) polar/lateral intercellular transport and another for IAA-mediated cell wall loosening. For each of these phenomena, a circuit/subsystem diagram highlights missing components (either in the logic circuit or in the subsystem it supervises) that must be identified experimentally if each of these basic plant phenomena is to be fully understood. We also illustrate the "subsystem incompleteness theorem," which states that no subsystem is operationally self-sufficient. Indeed, a whole-organism perspective is required to understand even the most simple morphogenetic process, because, when isolated, every biological signal-activated subsystem is morphogenetically ineffective.

  17. Comparative evaluation of distributed-collector solar thermal electric power plants

    Science.gov (United States)

    Fujita, T.; El Gabalawi, N.; Herrera, G. G.; Caputo, R. S.

    1978-01-01

    Distributed-collector solar thermal-electric power plants are compared by projecting power plant economics of selected systems to the 1990-2000 timeframe. The approach taken is to evaluate the performance of the selected systems under the same weather conditions. Capital and operational costs are estimated for each system. Energy costs are calculated for different plant sizes based on the plant performance and the corresponding capital and maintenance costs. Optimum systems are then determined as the systems with the minimum energy costs for a given load factor. The optimum system is comprised of the best combination of subsystems which give the minimum energy cost for every plant size. Sensitivity analysis is done around the optimum point for various plant parameters.

  18. Simulation of a solar collector array consisting of two types of solar collectors, with and without convection barrier

    DEFF Research Database (Denmark)

    Bava, Federico; Furbo, Simon; Perers, Bengt

    2015-01-01

    The installed area of solar collectors in solar heating fields is rapidly increasing in Denmark. In this scenario even relatively small performance improvements may lead to a large increase in the overall energy production. Both collectors with and without polymer foil, functioning as convection...... barrier, can be found on the Danish market. Depending on the temperature level at which the two types of collectors operate, one can perform better than the other. This project aimed to study the behavior of a 14 solar collector row made of these two different kinds of collectors, in order to optimize...... the composition of the row. Actual solar collectors available on the Danish market (models HT-SA and HT-A 35-10 manufactured by ARCON Solar A/S) were used for this analysis. To perform the study, a simulation model in TRNSYS was developed based on the Danish solar collector field in Braedstrup. A parametric...

  19. A Self-Biasing Pulsed Depressed Collector

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Mark A.; Jensen, Aaron; Neilson, Jeff; /SLAC

    2014-05-29

    Depressed collectors have been utilized successfully for many years to improve the electrical efficiency of vacuum electron devices. Increasingly, pulsed, high-peak power accelerator applications are placing a premium on electrical efficiency. As RF systems are responsible for a large percentage of the overall energy usage at accelerator laboratories, methods to improve upon the state-of-the-art in pulsed high-power sources are desired. This paper presents a technique for self-biasing the stages in a multistage depressed collector. With this technique, the energy lost during the rise and fall times of the pulse can be recovered, separate power supplies are not needed, and existing modulators can be retrofitted. Calculations show that significant cost savings can be realized with the implementation of this device in high-power systems. In this paper, the technique is described along with experimental demonstration. (auth)

  20. Installation package for a solar-heating system

    Science.gov (United States)

    1980-01-01

    Package consists of installation, operation and maintenance manuals for four commercial solar energy subsystems, including flat plate solar collector pebble bed thermal-storage. Manual gives design information, sizing data, specification drawings, and other material for subsystem.

  1. Assessment of musculoskeletal load in refuse collectors

    Directory of Open Access Journals (Sweden)

    Zbigniew W. Jóźwiak

    2013-08-01

    Full Text Available Background: The aim of this work was to assess the load on the musculoskeletal system and its effects in the collectors of solid refuse. The rationale behind this study was to formulate proposals how to reduce excessive musculoskeletal load in this group of workers. Material and Methods: The study group comprised 15 refuse collectors aged 25 to 50 years. Data about the workplace characteristics and subjective complaints of workers were collected by the free interview and questionnaire. During the survey the photorecording of the workpostures, the distance and velocity by GPS recorders, measurements of forces necessary to move containers, energy expenditure (lung ventilation method, workload estimation using the Firstbeat system and REBA method and stadiometry were done. Results: The distance walked daily by the collectors operating in terms of 2 to 3 in urban areas was about 15 km, and in rural areas about 18 km. The most frequent musculoskeletal complaints concerned the feet (60% subjects, knees, wrists and shoulders (over 40% subjects. After work-shift all examined workers had vertebral column shorter by 10 to 14 mm (11.4 mm mean. Conclusions: The results of our study show that the refuse collectors are subjected to a very high physical load because of the work organization and the way it is performed. To avoid adverse health effects and overload it is necessary to undertake ergonomic interventions, involving training of workers to improve the way of their job performance, active and passive leisure, technical control of the equipment and refuse containers, as well as the renegotiation of contracts with clients, especially those concerning non-standard containers. Med Pr 2013;64(4:507–519

  2. Theoretical study of fluidized solar collector performance

    Energy Technology Data Exchange (ETDEWEB)

    Adulla, S. H; Kassem, M A; El-Refaie, M. F. [Cairo University, Giza (Egypt)

    2000-07-01

    This work presents a proposed novel design aiming to increasing the absorber-to-fluid heat transfer coefficient. This is accomplished by introducing small solid particles inside the collector tubes. When the collector liquid flows, it causes the particles to be fluidized and spread in the tubes. The particles material, size and total number should be turned together with the fluid mass flow rate to keep the bed, or particle dispersion, length within the physical length of collector tubes. Thus, the particles would be confined in the collector only; and not carried over to other parts of the circulation loop. While moving, the particles erode the thermal boundary layer formed on the tube inner surface, hence increasing the heat transfer coefficient. [Spanish] Este articulo presenta un diseno novedoso destinado a aumentar el coeficiente de trasferencia de calor de absorbedor a fluido. Esto se lleva a cabo mediante la introduccion de particulas solidas dentro de los tubos del colector. Cuando fluye el liquido del colector origina que las particulas se fluidicen y se diseminen en los tubos. El material de las particulas, tamano y numero total debera de ser puesto en movimiento junto con el regimen de flujo de masa de fluido para mantener el lecho o la dispersion de particulas por largo tiempo dentro de la longitud fisica de los tubos de colector. De esta manera las particulas seran confinadas solamente en el colector y no seran arrastradas a otras partes del anillo de circulacion. Al moverse, las particulas erosionan la capa de frontera termica formada en la superficie interior del tubo, aumentando por tanto el coeficiente de transmision de calor.

  3. Protection of solar collector materials from UV

    Science.gov (United States)

    Castle, J. G., Jr.; Gause, R. L.; Whitaker, A.

    1978-01-01

    Certain plastic films, such as KAPTON, are known to be stable with excellent long-term aging characteristics under intense uv radiation. Our recent measurements of the optical transmission spectra of KAPTON films show an absorption edge in the blue and are interpreted in terms of an electronic excitation mechanism. The application of this type of film as covering for solar collectors is discussed in regard to the protection this strong uv absorption offers to the materials underneath.

  4. Indoor test and long-term weathering effects on the thermal performance of the solar energy system (liquid) solar collector. [Marshall Space Flight Center solar test facility and solar simulator

    Science.gov (United States)

    1979-01-01

    The procedures used and the results obtained during the evaluation test program on a liquid solar collector are presented. The narrow flat plate collector with reflective concentrating mirrors uses water as the working fluid. The double-covered collector weighs 137 pounds and has overall dimensions of about 35" by 77" by 6.75". The test program was conducted to obtain the following information: thermal performance data under simulated conditions, structural behavior under static load, and the effects of long term exposure to natural weathering.

  5. Development of computer simulation models for pedestrian subsystem impact tests

    NARCIS (Netherlands)

    Kant, R.; Konosu, A.; Ishikawa, H.

    2000-01-01

    The European Enhanced Vehicle-safety Committee (EEVC/WG10 and WG17) proposed three component subsystem tests for cars to assess pedestrian protection. The objective of this study is to develop computer simulation models of the EEVC pedestrian subsystem tests. These models are available to develop a

  6. A Structural Design of Insulated and Heat Conduction Ceramic Plate Used in Two Stage Depressed Collectors%一种应用于两级降压收集极的绝缘导热瓷件的结构设计

    Institute of Scientific and Technical Information of China (English)

    骆岷; 杨定义; 周明干

    2012-01-01

    A structural design of insulated and heat conduction ceramic plate,which think about material choice, insulated space and so on. And the design results used in practice.%介绍了一种绝缘导热瓷件的结构设计,从材料的选择、绝缘距离的考虑等方面进行了考虑,给出了设计结果及实际应用情况.

  7. Simulating the Various Subsystems of a Coal Mine

    Directory of Open Access Journals (Sweden)

    V. Okolnishnikov

    2016-06-01

    Full Text Available A set of simulation models of various subsystems of a coal mine was developed with the help of a new visual interactive simulation system of technological processes. This paper contains a brief description of this simulation system and its possibilities. The main possibilities provided by the simulation system are: the quick construction of models from library elements, 3D representation, and the communication of models with actual control systems. These simulation models were developed for the simulation of various subsystems of a coal mine: underground conveyor network subsystems, pumping subsystems and coal face subsystems. These simulation models were developed with the goal to be used as a quality and reliability assurance tool for new process control systems in coal mining.

  8. Assessing Quality across Health Care Subsystems in Mexico

    Science.gov (United States)

    Puig, Andrea; Pagán, José A.; Wong, Rebeca

    2012-01-01

    Recent healthcare reform efforts in Mexico have focused on the need to improve the efficiency and equity of a fragmented healthcare system. In light of these reform initiatives, there is a need to assess whether healthcare subsystems are effective at providing high-quality healthcare to all Mexicans. Nationally representative household survey data from the 2006 Encuesta Nacional de Salud y Nutrición (National Health and Nutrition Survey) were used to assess perceived healthcare quality across different subsystems. Using a sample of 7234 survey respondents, we found evidence of substantial heterogeneity in healthcare quality assessments across healthcare subsystems favoring private providers over social security institutions. These differences across subsystems remained even after adjusting for socioeconomic, demographic, and health factors. Our analysis suggests that improvements in efficiency and equity can be achieved by assessing the factors that contribute to heterogeneity in quality across subsystems. PMID:19305224

  9. Energy transfer in double plate system dynamics

    Institute of Scientific and Technical Information of China (English)

    Katica (Stevanovic) Hedrih

    2008-01-01

    The study of energy transfer between coupled subsystems in a hybrid system is very important for applications. This paper presents an analytical analysis of energy transfer between plates of a visco-elastically connected double-plate system in free transversal vibrations. The analytical analysis shows that the visco-elastic connection between plates is responsible for the appearance of two-frequency regime in the time function, which corresponds to one eigen amplitude function of one mode, and also that time functions of different vibration modes are uncoupled, but energy transfer between plates in one eigen mode appears. It was shown for each shape of vibrations. Series of the two Lyapunov exponents corresponding to the one eigen amplitude mode are expressed by using the energy of the corresponding eigen amplitude time component.

  10. Presence in the IP Multimedia Subsystem

    Directory of Open Access Journals (Sweden)

    Ling Lin

    2007-01-01

    Full Text Available With an ever increasing penetration of Internet Protocol (IP technologies, the wireless industry is evolving the mobile core network towards all-IP network. The IP Multimedia Subsystem (IMS is a standardised Next Generation Network (NGN architectural framework defined by the 3rd Generation Partnership Project (3GPP to bridge the gap between circuit-switched and packet-switched networks and consolidate both sides into on single all-IP network for all services. In this paper, we provide an insight into the limitation of the presence service, one of the fundamental building blocks of the IMS. Our prototype-based study is unique of its kind and helps identifying the factors which limit the scalability of the current version of the presence service (3GPP TS 23.141 version 7.2.0 Release 7 [1], which will in turn dramatically limit the performance of advanced IMS services. We argue that the client-server paradigm behind the current IMS architecture does not suite the requirements of the IMS system, which defies the very purpose of its introduction. We finally elaborate on possible avenues for addressing this problem.

  11. Mathematical Model of Double Pass Photovoltaic Thermal Air Collector with Fins

    Directory of Open Access Journals (Sweden)

    Ebrahim M.A. Alfegi

    2009-01-01

    Full Text Available Problem statement: The efficiency of photovoltaic cells is generally temperature dependent (efficiency decrease when the temperature of the photovoltaic cells increase. This problem can be solved by cooling the solar cells during operation and operated at low temperature. Approach: This study presented a numerical model of double pass Photovoltaic Thermal (PV/T solar air collector with fins attached to the back side of the absorber plate to improve heat transfer to the flowing air for predicting the performance of the system. Results: Five coupled of unsteady nonlinear partial differential equations were formulated by using first order forward scheme in time and second order central difference scheme in space to predict the performance of PV/T solar air heater at different parameters and conditions. The temperatures of the solar cells, outlet fluid temperature and the temperature distribution of every static element in both models were predicted. The performance of the collector including photovoltaic, thermal and combined PV/T collector over range of operating conditions are discussed. Conclusion: Experimental and theoretical results were compared and showed that close agreement between these two values were obtained.

  12. Solar collector exergetic optimization for a multi effect humidification desalination prototype

    Directory of Open Access Journals (Sweden)

    R González-Acuña

    2016-09-01

    Full Text Available Venezuela is a country with a great deal of water resources. In spite of this, about 1.6 million inhabitants are dispersed in remote regions where water distribution is problematic due to the lack of this resource. A flat plate solar collector was built as a component of a single-stage Multi-Effect Humidification (MEH desalination plant prototype, and its characterization was done on a testing rig designed and constructed according to the ANSI/ASHRAE 93-2003 standards. In order to optimize the operation of this equipment, the exergetic change of the working fluid across the solar collector was maximized. This objective was accomplished through a numerical simulation of the solar collector performance using a predictive algorithm and available yearlong meteorological data. It was found that a mass flow rate equal to 0.006 kg/s (0.36 LPM should be maintain to ensure the maximum exergetic gain of the working fluid for an inlet temperature of 54°C.

  13. 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.

  14. Investigations for effect of Al2O3–H2O nanofluid flow rate on the efficiency of direct absorption solar collector

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Gupta

    2015-03-01

    Full Text Available The efficiency of conventional tube‐ in plate type solar collectors is limited due to higher heat losses for surface based solar energy absorption and indirect transfer of heat from hot absorber surface to working fluid having poor heat transfer properties flowing through tubes. In this paper, a prototype direct absorption solar collector having gross area 1.4 m2 working on volumetric absorption principle is developed to investigate the effect of using Al2O3–H2O nanofluid as heat transfer fluid at different flow rates. Experimentation was carried using distilled water and 0.005% volume fractions of 20 nm size Al2O3 nanoparticles at three flow rates of 1.5, 2 and 2.5 lpm. ASHRAE standard 93-86 was followed for calculation of instantaneous efficiency of solar collector. Use of nanofluid improves the optical and thermo physical properties that result into an increase in the efficiency of the collector in all cases of using nanofluids in place of water. Collector efficiency enhancement of 8.1% and 4.2% has been observed for 1.5 and 2 lpm flow rate of nanofluid respectively. Optimum flow rate of 2.5 and 2 lpm towards maximum collector efficiency have also been observed for water and nanofluid respectively.

  15. An improved dynamic test method for solar collectors

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Wang, Zhifeng; Fan, Jianhua

    2012-01-01

    A comprehensive improvement of the mathematical model for the so called transfer function method is presented in this study. This improved transfer function method can estimate the traditional solar collector parameters such as zero loss coefficient and heat loss coefficient. Two new collector...... parameters t and mfCf are obtained. t is a time scale parameter which can indicate the heat transfer ability of the solar collector. mfCf can be used to calculate the fluid volume content in the solar collector or to validate the regression process by comparing it to the physical fluid volume content...... if known. Experiments were carried out under dynamic test conditions and then test data were processed using multi-linear regression method to get collector parameters with statistic analysis. A comparison of the collector parameters obtained from the improved transfer function (ITF) method and the quasi...

  16. Solar collector design with respect to moisture problems

    DEFF Research Database (Denmark)

    Holck, Ole; Svendsen, Svend; Brunold, Stefan;

    2003-01-01

    .Simulation of the microclimate in solar thermal collectors can be a valuable tool for optimisation of the collector with respect to ventilation. A computer model has been established for fulfilling this. By using this tool the producers can be advised whether their solar collectors ought to be additionally tightened, or whether...... group Materials in Solar Thermal Collectors of the International Energy Agency-Solar Heating and Cooling Programme....... the design of the collector, the location and size of ventilation holes, properties of the insulation materials and dimension of the solar collector box are parameters that have to be taken into account for the optimisation in order to achieve the most favourable microclimate to prevent corrosion...

  17. Effect of dividing daylight in symmetric prismatic daylight collector

    Science.gov (United States)

    Yeh, Shih-Chuan; Lu, Ju-Lin; Cheng, Yu-Chin

    2017-04-01

    This paper presented a symmetric prismatic daylight collector to collect daylight for the natural light illumination system. We analyzed the characteristics of the emerging light when the parallel light beam illuminate on the horizontally placed symmetric prismatic daylight collector. The ratio of the relative intensities of collected daylight that emerging from each surface of the daylight collector shown that the ratio is varied with the incident angle during a day. The simulation of the emerging light of the daylight collector shown that the ratio of emerging light is varied with the tilted angle when sunshine illuminated on a symmetric prismatic daylight collector which was not placed horizontally. The integration of normalized intensity is also varied with the tilted angle. The symmetric prismatic daylight collector with the benefits of reducing glare and dividing intensity of incident daylight, it is applicable to using in the natural light illumination system and hybrid system for improving the efficiency of utilizing of solar energy.

  18. Mathematical Modeling of Dual Intake Transparent Transpired Solar Collector

    OpenAIRE

    Thomas Semenou; Rousse, Daniel R.; Brice Le Lostec; Hervé F. Nouanegue; Pierre-Luc Paradis

    2015-01-01

    Nowadays, in several types of commercial or institutional buildings, a significant rise of transpired solar collectors used to preheat the fresh air of the building can be observed. Nevertheless, when the air mass flow rate is low, the collector efficiency collapses and a large amount of energy remains unused. This paper presents a simple yet effective mathematical model of a transparent transpired solar collector (TTC) with dual intake in order to remove stagnation problems in the plenum and...

  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...... in Europe. The collector parameters used as input in the tool are compiled from tests according to EN12975, without any intermediate conversions. The main target group for this tool is test institutes and certification bodies that are intended to use it for conversion of collector model parameters (derived...

  20. Simulation Application for Optimization of Solar Collector Array

    Directory of Open Access Journals (Sweden)

    Igor Shesho*,

    2014-01-01

    Full Text Available Solar systems offer a comparatively low output density , so increasing the output always means a corresponding increase in the size of the collector area. Thus collector arrays are occasionally constructed (i.e. with different azimuth angles and/or slopes, which be imposed by the location and structure available to mount the collector. In this paper is developed simulation application for optimization for the solar collector array position and number of collectors in regard of maximum annual energy gain and thermal efficiency. It is analyzed solar collector array which has parallel and serial connected solar collectors with different tilt, orientation and thermal characteristics. Measurements are performed for determine the thermal performance of the system. Using the programming language INSEL it is developed simulation program for the analyzed system where optimization is done through parametric runs in the simulation program. Accent is given on the SE orientated collectors regarding their tilt and number, comparing two solutions-scenarios and the current system set situation of the in means of efficiency and total annual energy gain. The first scenario envisages a change of angle from 35 to 25 solar panels on the SE orientation, while the second scenario envisages retaining the existing angle of 35 and adding additional solar collector. Scenario 1 accounts for more than 13% energy gain on annual basis while Scenario 2 has 2% bigger thermal efficiency.

  1. Design and performance of multi-purpose vacuum solar collector

    Science.gov (United States)

    Balotaki, H. Kavoosi; Saidi, M. H.

    2017-09-01

    Design and fabrication of solar collectors with high performance of energy efficiency to convert solar energy to utility energy is vitally important. This article reports the results obtained from design, construction and investigation of the performance of a Combined Multi-Purpose Vacuum Solar Collector (CMPVSC). This collector consists of three sections: the vacuum section, the liquid section and the air section. In the present collector, it is capable of transferring heat to two flows (liquid and air) simultaneously and separate with the possibility of multipurpose applications. The CMPVSC is compared with the existing individual collectors and the effects of different parameters on the efficiency of this collector are examined. Experimental data indicate that high temperature and high performance with a 43% reduction in cost can be obtained using CMPVSC compared to two individual collectors. To increase the efficiency of the collector, triangular and rectangular channels in the air section have been used. The vacuum part is implemented to reduce heat losses. The effect of water inlet temperature, air flow rate, shape of air channel and vacuum part on the heat delivery by air and water have been investigated. Furthermore, as a matter of comparison of CMPVSC with the individual collector, there is a chance of obtaining highest temperature and efficiency with minimum cost and space requirements.

  2. Some new aspects of the coupon-collector's problem

    OpenAIRE

    Myers, Amy N.; Wilf, Herbert S.

    2003-01-01

    We extend the classical coupon collector's problem to one in which two collectors are simultaneously and independently seeking collections of $d$ coupons. We find, in finite terms, the probability that the two collectors finish at the same trial, and we find, using the methods of Gessel-Viennot, the probability that the game has the following ``ballot-like'' character: the two collectors are tied with each other for some initial number of steps, and after that the player who first gains the l...

  3. Study on the Effect of the Curvature of Solar Collector on Wind Loading Coefficients and Dynamic Response of Solar Collector

    Directory of Open Access Journals (Sweden)

    Khalid Hameed Hussein

    2013-01-01

    Full Text Available In the current research, the work concentrated on studying the effect of curvature of solar parabolic trough solar collector on wind loading coefficients and dynamic response of solar collector. The response of collector to the aerodynamic loading was estimated numerically and experimentally. The curvature of most public parabolic trough solar collectors was investigated and compared. The dynamic response of solar collector due to wind loading was investigated by using numerical solution of fluid-structure interaction concept. The experimental work was done to verify the numerical results and shows good agreement with numerical results. The numerical results were obtained by using finite element software package (ANSYS 14. It was found that the change in collector curvature (focal length lead to remarkable changes in wind loading coefficients (drag, lift, and moment, dynamic response (displacement and natural frequencies but does not affect the first mode shape.

  4. The Estimation of Vibrational Energy of Two Coupled (Welded Plates Using Statistical Energy Analysis

    Directory of Open Access Journals (Sweden)

    Hawraa S. Ibraham

    2011-01-01

    Full Text Available This paper deals with a method called Statistical Energy Analysis that can be applied to the mechanical and acoustical systems like buildings, bridges and aircrafts …etc. S.E.A as a tool can be applied to the resonant systems in the circumstances of high frequency or/and complex structure». The parameters of S.E.A such as coupling loss factor, internal loss factor, modal density and input power are clarified in this work ; coupled plate sub-systems and explanations are presented for these parameters. The developed system is assumed to be resonant, conservative, linear and there is an equipartition of energy between all the resonant modes within a given frequency band in a given sub-system. The aim of this work is to find the energy stored in the sub-systems for two coupled (welded plates in rectangular angle systems and study the effect of changing sub-systems dimensions, the results shows that as surface area of directly driven plates A1 increases energy level of plate 1 increases while a reduction in the energy level of indirectly driven plate (plate 2 is noticed. This is because of the strength of coupling decreases towards the weak coupling condition and this leads to a reduction in the power transferred from plate 1 to plate 2 and consequently a lower energy level for plate 2. In addition the effect of changing the internal loss factor for a range of (0.00001-0.1 causes a reduction of the values of energy level in these sub-systems. because the increasing of internal loss factor values led to the increasing of the material resistance and that will dissipate the energy flow across those sub-systems. A comparison is made between S.E.A models built by FORTRAN program and Finite Element model solved by ANSYS package.

  5. MSG Power Subsystem Flight Return Experience

    Science.gov (United States)

    Giacometti, G.; Canard, JP.; Perron, O.

    2011-10-01

    The Meteosat programme has been running for more than twenty years under ESA leadership. Meteosat Second Generation (MSG) is a series of 4 geostationary satellites developed and procured by the European Space Agency (ESA) on behalf of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). Eumetsat is still operating two of the first generation satellites models named MOP3 and MTP1 which are pointed towards the Indian ocean. The European meteorological service is now enhanced by two spacecrafts of the Second Generation (MSG-1 and MSG-2). They have been launched by Ariane 5 in August 2002 and December 2005 respectively. Thales Alenia Space, Prime Contractor of the program, has developed the MSG spacecraft based on a spin-axis stabilized technology. The Electrical Power Subsystem was subcontracted to Astrium GmbH. The Solar Array is composed of 8 body mounted panels, based on Carbon Fibre Reinforced Panel substrate. The Solar network utilizes 7854 Silicon High Eta cells delivering a beginning of life power of 740W. The 28 volts mainbus is regulated using a series shunt regulating concept (S3R type). Two identical SAFT batteries, built from NiCd cells and offering a 29Ah nameplate capacity are connected to the mainbus through battery discharge and charge regulators. Both Solar Array and batteries have been designed to provide power and energy for a nominal 7 years lifetime. These equipments are continuously monitored and are still operating in excellent condition after more than eight and five years in orbit. This paper will present the major electrical design aspects of the power chain and will describe the main parameters performances, which are analysed during the in-orbit operations. Batteries ageing is detailed thanks to reconditioning processed telemetry while the solar array performances over lifetime use dedicated solar array telemetry.

  6. CMS DT Upgrade The Sector Collector Relocation

    CERN Document Server

    Navarro Tobar, Alvaro

    2015-01-01

    The Sector Collector relocation is the first stage of the upgrade program for the Drift Tubes subdetector of the CMS experiment. It was accomplished during Long Shutdown 2013-2014, and consisted in the relocation of the second-level trigger and readout electronics from the experimental to the service cavern, relieving the environmental constraints and improving accessibility for maintenance and upgrade. Extending the electrical links would degrade reliability, so the information is converted to optical with a custom system capable of dealing with the DC-unbalanced data. Initially, present electronics are used, so optical-to-copper conversion has also been installed.

  7. Mobile Information Collectors' Trajectory Data Warehouse Design

    CERN Document Server

    oueslati, wided

    2010-01-01

    To analyze complex phenomena which involve moving objects, Trajectory Data Warehouse (TDW) seems to be an answer for many recent decision problems related to various professions (physicians, commercial representatives, transporters, ecologists ...) concerned with mobility. This work aims to make trajectories as a first class concept in the trajectory data conceptual model and to design a TDW, in which data resulting from mobile information collectors' trajectory are gathered. These data will be analyzed, according to trajectory characteristics, for decision making purposes, such as new products commercialization, new commerce implementation, etc.

  8. Adaptive control of solar energy collector systems

    CERN Document Server

    Lemos, João M; Igreja, José M

    2014-01-01

    This book describes methods for adaptive control of distributed-collector solar fields: plants that collect solar energy and deliver it in thermal form. Controller design methods are presented that can overcome difficulties found in these type of plants:they are distributed-parameter systems, i.e., systems with dynamics that depend on space as well as time;their dynamics is nonlinear, with a bilinear structure;there is a significant level of uncertainty in plant knowledge.Adaptive methods form the focus of the text because of the degree of uncertainty in the knowledge of plant dynamics. Parts

  9. Investigations for effect of Al2O3–H2O nanofluid flow rate on the efficiency of direct absorption solar collector

    OpenAIRE

    Hemant Kumar Gupta; Ghanshyam Das Agrawal; Jyotirmay Mathur

    2015-01-01

    The efficiency of conventional tube‐ in plate type solar collectors is limited due to higher heat losses for surface based solar energy absorption and indirect transfer of heat from hot absorber surface to working fluid having poor heat transfer properties flowing through tubes. In this paper, a prototype direct absorption solar collector having gross area 1.4 m2 working on volumetric absorption principle is developed to investigate the effect of using Al2O3–H2O nanofluid as heat transfer flu...

  10. Development of a preprototype times wastewater recovery subsystem

    Science.gov (United States)

    Roebelen, G. J., Jr.; Dehner, G. F.

    1982-01-01

    A three-man wastewater recovery preprototype subsystem using a hollow fiber membrane evaporator with a thermoelectric heat pump to provide efficient potable water recovery from wastewater on extended duration space flights was designed, fabricated, and tested at one-gravity. Low power, compactness and gravity insensitive operation are featured in this vacuum distillation subsystem. The tubular hollow fiber elements provide positive liquid/gas phase control with no moving parts, and provide structural integrity, improving on previous flat sheet membrane designs. A thermoelectric heat pump provides latent energy recovery. Application and integration of these key elements solved problems inherent in all previous reclamation subsystem designs.

  11. Space Shuttle Orbiter leading edge structural subsystem thermal performance

    Science.gov (United States)

    Curry, D. M.; Cunningham, J. A.; Frahm, J. R.

    1982-01-01

    An extensive qualification test program and the STS-1 flight of the Space Shuttle Orbiter have provided the data necessary to verify the performance of the Orbiter thermal protection system. The reinforced carbon-carbon leading edge structural subsystem is used on areas of the orbiter where temperatures exceed 2300 F. The subsystem consists of the ROC nose cap and wing leading edge panels, metallic attachments, internal insulation, and interface tiles. Thermal response data from the qualification tests and the STS-1 flight, postflight inspection, and analytical predictions support the conclusion that the thermal performance of the subsystem verified the design.

  12. Improvement of black nickel coatings. [product development for use in solar collectors

    Science.gov (United States)

    Peterson, R. E.; Lin, J. H.

    1976-01-01

    Selectively absorbing black nickel coatings are among the most optically efficient low cost coatings for use on flat plate solar collectors. However, a current Ni-Zn-S-O coating in use is quite susceptible to a humid environment, degrading badly in less than ten days at 38 C (100 F) at 95 percent relative humidity. Therefore, a black nickel formula was developed which can withstand such exposures with no loss of optical efficiency, solar absorption of 0.92 and an infrared emittance (at 100 C) of 1.00 were still present after 14 days of humidity exposure. This compares to a solar absorptance of only 0.72 for the previous formula after a similar time period. The electroplating bath and conditions were changed to obtain the more stable coating configuration. The effect of bath composition, temperature, pH, and plating current density and time on the coating composition, spectral optical properties and durability were investigated systematically.

  13. Assessment of Energy, Environmental and Economic Performance of a Solar Desiccant Cooling System with Different Collector Types

    Directory of Open Access Journals (Sweden)

    Giovanni Angrisani

    2014-10-01

    Full Text Available Desiccant-based air handling units can achieve reductions in greenhouse gas emissions and energy savings with respect to conventional air conditioning systems. Benefits are maximized when they interact with renewable energy technologies, such as solar collectors. In this work, experimental tests and data derived from scientific and technical literature are used to implement a model of a solar desiccant cooling system, considering three different collector technologies (air, flat-plate and evacuated collectors. Simulations were then performed to compare the energy, environmental and economic performance of the system with those of a desiccant-based unit where regeneration thermal energy is supplied by a natural gas boiler, and with those of a conventional air-handling unit. The only solution that allows achieving the economic feasibility of the solar desiccant cooling unit consists of 16 m2 of evacuated solar collectors. This is able to obtain, with respect to the reference system, a reduction of primary energy consumption and of the equivalent CO2 emissions of 50.2% and 49.8%, respectively, but with a payback time of 20 years.

  14. New concepts for solar collectors in 2030

    Energy Technology Data Exchange (ETDEWEB)

    Bakker, M.; Van Helden, W. [ECN Efficiency and Infrastructure, Petten (Netherlands); Nijs, J.; Reinders, A. [University of Twente, Faculty of CTW, Department of Design, Production and Management, Enschede (Netherlands)

    2009-01-15

    In 2030, solar energy is expected to cover the full energy demand of newly built houses. In addition, increasing standards for quality of living require that newly built houses offer increased comfort, while still being affordable. Current collector technology will not be able to meet all these requirements; hence, new collector concepts are required. This paper develops new concepts for the capture, conversion, and storage of solar energy with a focus on future integration in newly built houses. Industrial design engineering was used in the concept development, including an analysis of the field as well as a series of workshops. Out of several concepts, two were selected and elaborated. The first concept (aimed at 2015) is based on a passive house, and is able to fully provide the domestic energy use of both the user and the building itself. The second concept (aimed at 2030) integrates energy production, energy storage, building insulation, and an indoor climate system in durable, modular construction elements; the total energy production of this concept exceeds the total domestic energy use. This paper illustrates the concept development process and its results.

  15. Triple3 Redundant Spacecraft Subsystems (T3RSS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — T3RSS is the system engineer's tool that allows a systematic approach to ensuring that even if one or more failures occur in a single component or subsystem, then...

  16. Review of Decoherence Free Subspaces, Noiseless Subsystems, and Dynamical Decoupling

    CERN Document Server

    Lidar, Daniel A

    2012-01-01

    Quantum information requires protection from the adverse affects of decoherence and noise. This review provides an introduction to the theory of decoherence-free subspaces, noiseless subsystems, and dynamical decoupling. It addresses quantum information preservation as well protected computation.

  17. Double Shell Tank (DST) Monitor and Control Subsystem Specification

    Energy Technology Data Exchange (ETDEWEB)

    BAFUS, R.R.

    2000-11-03

    This specification revises the performance requirements and provides references to the requisite codes and standards to be applied during design of the Double-Shell Tank (DST) Monitor and Control Subsystem that supports the first phase of Waste Feed Delivery.

  18. Development of Pattern Recognition Options for Combining Safeguards Subsystems

    Energy Technology Data Exchange (ETDEWEB)

    Burr, Thomas L. [Los Alamos National Laboratory; Hamada, Michael S. [Los Alamos National Laboratory

    2012-08-24

    This talk reviews project progress in combining process monitoring data and nuclear material accounting data to improve the over nuclear safeguards system. Focus on 2 subsystems: (1) nuclear materials accounting (NMA); and (2) process monitoring (PM).

  19. Double Shell Tank (DST) Process Waste Sampling Subsystem Specification

    Energy Technology Data Exchange (ETDEWEB)

    RASMUSSEN, J.H.

    2000-05-03

    This specification establishes the performance requirements and provides references to the requisite codes and standards to be applied to the Double-Shell Tank (DST) Process Waste Sampling Subsystem which supports the first phase of Waste Feed Delivery.

  20. Macrofauna Settlement on Pearl Oyster Collectors in Kenya ...

    African Journals Online (AJOL)

    Abstract—Collection of pearl oyster seed using artificial collectors is a critical step in the production of cultured ... settled on spat collectors set to collect Pinctada margaritifera and Pteria penguin seed in shallow ... experiments conducted in Kenya between 2002 and. 2005. ..... the macrofauna and the bivalves follow a similar.

  1. 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...

  2. Design and fabrication considerations of EUVL collectors for HVM

    Science.gov (United States)

    Bianucci, G.; Cassol, G. L.; Kools, J.; Prea, M.; Salmaso, G.; Valsecchi, G.; Zocchi, F. E.; Bolshukhin, D.; Schürmann, M.; Schriever, G.; Mader, A.; Zink, P.

    2009-03-01

    The power roadmap for EUVL high volume manufacturing (HVM) exceeds the 200W EUV in-band power at intermediate focus, thus posing more demanding requirements on HVM sources, debris suppression systems and collectors. Starting from the lessons learned in the design and fabrication of the grazing incidence collectors for the Alpha EUVL scanners, Media Lario Technologies is developing HVM optical solutions that enable designed-in lifetime improvements, such as larger source-collector distances, optimized collection efficiency through larger collected solid angles, and customized EUV reflective layers. The optical design of an HVM collector is described together with the selection of the sacrificial ruthenium reflective layer. The water cooling layout of the collector is evolved from the integrated cooling technology developed at Alpha level into an innovative cooling layout that minimizes the thermal gradients across the mirrors and allows controlling the optical performance at the far-field plane. Finally, the evolution of the collector's manufacturing technologies for HVM is discussed. XTREME technologies and Philips Extreme UV support this work by integrating the collector in the complete source collector module (SoCoMo). At system level, each component of the SoCoMo is part of a development and improvement plan leading to a comprehensive system that will fulfill the 200+ W EUV in-band power at intermediate focus.

  3. Thermal performance of a hot-air solar collector

    Science.gov (United States)

    1978-01-01

    Report contains procedures and results of thermal-performance tests on double-glazed air solar collector. Four types of tests were carried out including thermal-efficiency and stagnation tests, collector time-constant tests to assess effects of transients, and incident-angle modifier tests. Data are presented in tables and as graphs and are discussed and analyzed.

  4. Statistical Design Model (SDM) of satellite thermal control subsystem

    Science.gov (United States)

    Mirshams, Mehran; Zabihian, Ehsan; Aarabi Chamalishahi, Mahdi

    2016-07-01

    Satellites thermal control, is a satellite subsystem that its main task is keeping the satellite components at its own survival and activity temperatures. Ability of satellite thermal control plays a key role in satisfying satellite's operational requirements and designing this subsystem is a part of satellite design. In the other hand due to the lack of information provided by companies and designers still doesn't have a specific design process while it is one of the fundamental subsystems. The aim of this paper, is to identify and extract statistical design models of spacecraft thermal control subsystem by using SDM design method. This method analyses statistical data with a particular procedure. To implement SDM method, a complete database is required. Therefore, we first collect spacecraft data and create a database, and then we extract statistical graphs using Microsoft Excel, from which we further extract mathematical models. Inputs parameters of the method are mass, mission, and life time of the satellite. For this purpose at first thermal control subsystem has been introduced and hardware using in the this subsystem and its variants has been investigated. In the next part different statistical models has been mentioned and a brief compare will be between them. Finally, this paper particular statistical model is extracted from collected statistical data. Process of testing the accuracy and verifying the method use a case study. Which by the comparisons between the specifications of thermal control subsystem of a fabricated satellite and the analyses results, the methodology in this paper was proved to be effective. Key Words: Thermal control subsystem design, Statistical design model (SDM), Satellite conceptual design, Thermal hardware

  5. A solar air collector with integrated latent heat thermal storage

    Science.gov (United States)

    Charvat, Pavel; Ostry, Milan; Mauder, Tomas; Klimes, Lubomir

    2012-04-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data).

  6. A solar air collector with integrated latent heat thermal storage

    Directory of Open Access Journals (Sweden)

    Klimes Lubomir

    2012-04-01

    Full Text Available Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data.

  7. FLOW DISTRIBUTION IN A SOLAR COLLECTOR PANEL WITH HORIZONTAL FINS

    DEFF Research Database (Denmark)

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

    2005-01-01

    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 horizontal fins. 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 m² 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......, temperature of inlet flow and collector tilt angle are shown. Based on the investigations preliminary recommendations for the operation of the investigated collector are given. For instance, minimum flow rate in order to avoid boiling in the horizontal strips is recommended....

  8. Design wind and sandstorm loads on trough collectors in fields

    Science.gov (United States)

    Gong, Bo; Wang, Zhifeng; Wei, Zeyu

    2017-06-01

    Trough collectors are laid out in rows in a field withrow spacing. Wind and sandstorm loads on the collectors will be influenced by surrounding collectors. This paper presents analyzed results from a combined wind tunnel and sandstorm tunnel study on a trough collector field with seven rows and five spans. In wind tunneltests, the measured model with pressure taps was installed in the field to measure wind pressures on the surfaces. Mean and fluctuating pressures on the model were measured by the synchronous multi-pressure sensing system under typical boundary layer wind flow field. In sandstorm tunneltests,a isolated trough collector model was measured by the high-frequency force balance technique under wind-blown sand flow field.

  9. Test results, Industrial Solar Technology parabolic trough solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Dudley, V.E. [EG and G MSI, Albuquerque, NM (United States); Evans, L.R.; Matthews, C.W. [Sandia National Labs., Albuquerque, NM (United States)

    1995-11-01

    Sandia National Laboratories and Industrial Solar Technology are cost-sharing development of advanced parabolic trough technology. As part of this effort, several configurations of an IST solar collector were tested to determine the collector efficiency and thermal losses with black chrome and black nickel receiver selective coatings, combined with aluminized film and silver film reflectors, using standard Pyrex{reg_sign} and anti-reflective coated Pyrex{reg_sign} glass receiver envelopes. The development effort has been successful, producing an advanced collector with 77% optical efficiency, using silver-film reflectors, a black nickel receiver coating, and a solgel anti-reflective glass receiver envelope. For each receiver configuration, performance equations were empirically derived relating collector efficiency and thermal losses to the operating temperature. Finally, equations were derived showing collector performance as a function of input insolation value, incident angle, and operating temperature.

  10. In situ built-up air collector with glass cover

    DEFF Research Database (Denmark)

    Kristiansen, Finn Harken; Engelmark, Jesper

    1998-01-01

    as an absorber. Efficiency and aair pressure drop were measured. The efficiency of the two air solar collectors was almost similar and at the same level as other corresponding air solar collectors. The air pressure drop was somewhat larger in the case of the solar collector where the air flows behind...... with a cover of glass where the horizontal joints were made by means of different methods and materials. As a general principle a water-damming border at the horizontal glass joints was avoided. The test box was built as a solar collector with 14 different horizontal joints between the glasses. The box...... the absorber. This is due to the narrower air gap behind the absorber. Condensation has been observed in both the solar collectors, this has not been investigated more explicitly,...

  11. Mathematical modelling of unglazed solar collectors under extreme operating conditions

    DEFF Research Database (Denmark)

    Bunea, M.; Perers, Bengt; Eicher, S.

    2015-01-01

    average temperature levels at the evaporator. Simulation of these systems requires a collector model that can take into account operation at very low temperatures (below freezing) and under various weather conditions, particularly operation without solar irradiation.A solar collector mathematical model......Combined heat pumps and solar collectors got a renewed interest on the heating system market worldwide. Connected to the heat pump evaporator, unglazed solar collectors can considerably increase their efficiency, but they also raise the coefficient of performance of the heat pump with higher...... was found due to the condensation phenomenon and up to 40% due to frost under no solar irradiation. This work also points out the influence of the operating conditions on the collector's characteristics.Based on experiments carried out at a test facility, every heat flux on the absorber was separately...

  12. Numerical analysis of the EHD driven flow with heat transfer in a smooth channel using multiple collectors

    Science.gov (United States)

    Taghavi Fadaki, S. S.; Amanifard, N.; Deylami, H. M.; Dolati, F.

    2017-02-01

    In the present study, a new design of collecting electrodes is studied for performing a higher performance in EHD phenomena in a smooth channel. The effect of the electric field on the heat transfer enhancement and swirling flow patterns for a new design of multiple collectors in a smooth channel is numerically investigated with 2-D approach. In this regard, the corona device configuration comprises a single fixed emitting wire situated at the centerline of the channel and different grounded electrode arrangements which are in two types of wire and plate. The results indicate that the multi-collector arrangements cause significant changes in the flow pattern, heat transfer coefficient and friction factor. Furthermore, it is found that the thermal enhancement factor has remarkable growth, and EHD efficiency for two types of wire and plate collectors is notable. Besides, as an outstanding result, the electrohydrodynamic phenomenon has a negative effect on the heat transfer enhancement depending upon the values of Reynolds number and applied electric potential.

  13. 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 %.

  14. EVALUATION OF FLAT-PLATE PHOTOVOLTAIC THERMAL HYBRID SYSTEMS FOR SOLAR ENERGY UTILIZATION.

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.W.

    1981-06-01

    The technical and economic attractiveness of combined photovoltaic/thermal (PV/T) solar energy collectors was evaluated. The study was limited to flat-plate collectors since concentrating photovoltaic collectors require active cooling and thus are inherently PV/T collectors, the only decision being whether to use the thermal energy or to dump it. it was also specified at the outset that reduction in required roof area was not to be used as an argument for combining the collection of thermal and electrical energy into one module. Three tests of economic viability were identified, all of which PV/T must pass if it is to be considered a promising alternative: PV/T must prove to be competitive with photovoltaic-only, thermal-only, and side-by-side photovoltaic-plus-thermal collectors and systems. These three tests were applied to systems using low-temperature (unglazed) collectors and to systems using medium-temperature (glazed) collectors in Los Angeles, New York, and Tampa. For photovoltaics, the 1986 DOE cost goals were assumed to have been realized, and for thermal energy collection two technologies were considered: a current technology based on metal and glass, and a future technology based on thin-film plastics. The study showed that for medium-temperature applications PV/T is not an attractive option in any of the locations studied. For low-temperature applications, PV/T appears to be marginally attractive.

  15. EVALUATION OF FLAT-PLATE PHOTOVOLTAIC THERMAL HYBRID SYSTEMS FOR SOLAR ENERGY UTILIZATION.

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.W.

    1981-06-01

    The technical and economic attractiveness of combined photovoltaic/thermal (PV/T) solar energy collectors was evaluated. The study was limited to flat-plate collectors since concentrating photovoltaic collectors require active cooling and thus are inherently PV/T collectors, the only decision being whether to use the thermal energy or to dump it. it was also specified at the outset that reduction in required roof area was not to be used as an argument for combining the collection of thermal and electrical energy into one module. Three tests of economic viability were identified, all of which PV/T must pass if it is to be considered a promising alternative: PV/T must prove to be competitive with photovoltaic-only, thermal-only, and side-by-side photovoltaic-plus-thermal collectors and systems. These three tests were applied to systems using low-temperature (unglazed) collectors and to systems using medium-temperature (glazed) collectors in Los Angeles, New York, and Tampa. For photovoltaics, the 1986 DOE cost goals were assumed to have been realized, and for thermal energy collection two technologies were considered: a current technology based on metal and glass, and a future technology based on thin-film plastics. The study showed that for medium-temperature applications PV/T is not an attractive option in any of the locations studied. For low-temperature applications, PV/T appears to be marginally attractive.

  16. Simulation of a solar collector array consisting of two types of solar collectors, with and without convection barrier

    DEFF Research Database (Denmark)

    Bava, Federico; Furbo, Simon; Perers, Bengt

    2015-01-01

    The installed area of solar collectors in solar heating fields is rapidly increasing in Denmark. In this scenario even relatively small performance improvements may lead to a large increase in the overall energy production. Both collectors with and without polymer foil, functioning as convection...... analysis was carried out by modifying the composition of the row, in order to find both the energy and economy optimum....... barrier, can be found on the Danish market. Depending on the temperature level at which the two types of collectors operate, one can perform better than the other. This project aimed to study the behavior of a 14 solar collector row made of these two different kinds of collectors, in order to optimize...

  17. Antireflection Pyrex envelopes for parabolic solar collectors

    Science.gov (United States)

    McCollister, H. L.; Pettit, R. B.

    1983-11-01

    Antireflective (AR) coatings, applied to the glass envelopes used in parabolic trough solar collectors around the receiver tube in order to reduce thermal losses, can increase solar transmittance by 7 percent. An AR surface has been formed on Pyrex by first heat treating the glass to cause a compositional phase separation, removing a surface layer after heat treatment through the use of a preetching solution, and finally etching in a solution that contains hydrofluorosilic and ammonium bifluoride acids. AR-coated samples with solar transmittance values of more than 0.97, by comparison to an untreated sample value of 0.91, have been obtained for the 560-630 C range of heat treatment temperatures. Optimum values have also been determined for the other processing parameters.

  18. DRYING WITH SOLAR COLLECTOR BY HEAT PIPE

    Directory of Open Access Journals (Sweden)

    Hikmet DOĞAN

    1999-01-01

    Full Text Available In this research, heating pipe was used in the solar collector in order to take better advantage of the solar energy. The energy obtained from the sun was transferred to the drying air by means of heating pipes and this hot air was blown on the material to be dried. The water on the material to be dried vaporised with the effect of the hot air and drying took place. Because drying took place in the shade, distant from the direct radiation effects of the sun, some of the disadvantages seen in drying outside, under the sun were eliminated. Additionally, it was observed that it took less time to dry in this method than it takes to dry under the open sun.

  19. Genesis Solar Wind Array Collector Cataloging Status

    Science.gov (United States)

    Burkett, P.J.; Rodriguez, M.C.; Calaway, M.C.; Allton, J.H.

    2009-01-01

    Genesis solar wind array collectors were fractured upon landing hard in Utah in 2004. The fragments were retrieved from the damaged canister, imaged, repackaged and shipped to the Johnson Space Center curatorial facility [1]. As of January 2009, the collection consists of 3460 samples. Of these, 442 are comprised into "multiple" sample groupings, either affixed to adhesive paper (177) or collected in jars (17), culture trays (87), or sets of polystyrene vials (161). A focused characterization task was initiated in May 2008 to document the largest samples in the collection. The task consisted of two goals: to document sapphire based fragments greater than 2 cm in one dimension, and to document silicon based fragments greater than 1 cm in one direction.

  20. 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.