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1

Radiant energy collector  

Energy Technology Data Exchange (ETDEWEB)

A cylindrical radiant energy collector is provided which includes a reflector spaced apart from an energy absorber. The reflector is of a particular shape which ideally eliminates gap losses. The reflector includes a plurality of adjacent facets of V shaped segments sloped so as to reflect all energy entering between said absorber and said reflector onto said absorber. The outer arms of each facet are sloped to reflect one type of extremal ray in a line substantially tangent to the lowermost extremity of the energy absorber. The inner arms of the facets are sloped to reflect onto the absorber all rays either falling directly thereon or as a result of reflection from an outer arm.

McIntire, William R. (Downers Grove, IL)

1983-01-01

2

Radiant energy collector having plasma-textured polyimide exposed surface  

Energy Technology Data Exchange (ETDEWEB)

A method of fabricating a radiant energy collector is disclosed wherein a substrate is coated on at least a portion of the surface to be exposed to radiant energy, with polyamide then surface-textured employing known procedures, e.g., plasma etching, reactive ion etching or a combination of these techniques, to impart to the coated surface high absorptivity and low emissivity for radiant energy.

Guarnieri, C. R.

1984-06-04

3

Radiant energy collector having plasma-textured polyimide exposed surface  

Energy Technology Data Exchange (ETDEWEB)

A radiant energy collector is disclosed which is fabricated from a substrate coated on at least a portion of the surface thereof exposed to radiant energy with polyimide which has been surface-textured employing known procedures, e.g., plasma etching, reactive ion etching or a combination of these techniques, to impart of said coated substrate high absorption and low emissivity for radiant energy, the surface of the substrate opposite that exposed to the radiant energy being in contact with a working fluid such as water.

Guarnieri, C.R.

1984-10-23

4

Radiant energy sensitive device and method  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a radiant energy sensitive device, it comprises: a first radiant energy transmissive, electrically conductive layer of tin oxide; a second radiant energy transmissive, electrically conductive layer of zinc oxide disposed upon the layer of tin oxide; and a radiant energy sensitive layer deposited upon the layer of zinc oxide.

Delahoy, A.E.

1991-11-12

5

Application of radiant heating saves energy  

Energy Technology Data Exchange (ETDEWEB)

Application of radiant principles is one of the best kept secrets of the 20th century. The purpose of this application can reduce energy requirements. The theory of energy release from a high temperature surface was first proposed as a commercial product in the early 1900s. This article provides an understanding of how transfer or radiant energy works, identifies the factors that contribute to its economical performance and demonstrates how applications of radiant heating can provide comfort with lower energy costs.

Buckley, N.A. (Buckley Assoc., Eden, NY (US))

1989-09-01

6

Comparative energy requirements of radiant space heating  

Energy Technology Data Exchange (ETDEWEB)

An analytical study compared the energy requirements for a total-building (primarily industrial) radiant space-heating system with those for a convection hot-air scheme. Modeling for the extreme conditions of 100% radiant to 100% convection heat input, the analysis indicated a 14/sup 0/F higher mean radiant temperature for 100% radiant heat than for convection heat with the result that the space-air temperature required for equal comfort was reduced by 14/sup 0/F with radiant heating. Furthermore, radiant heat transfer produced higher inside surface temperatures than the convection mode, although in both cases the surface temperatures were lower than the space-air temperature. Increasing the reflectivity of the wall and ceiling surfaces could raise the effective temperature of the space in radiant systems.

Bryan, W.L.

1981-01-01

7

Solar energy collector  

Energy Technology Data Exchange (ETDEWEB)

A solar energy collector is disclosed having a hollow, pyramidal-shaped body made of insulation material and a fluid conducting coil of heat conducting tubing extending around the inside of the body. The outer case or shell has a fluid coil to sense heat and cold of liquid flowing to the fluid bed. A plurality of sheets of rigid material support alternate layers of liquid and lenses which focus sunlight onto the layers of liquid and onto the coils of tubing thereby heating the liquid. The liquid in each of the coils is connected to separate thermostatically controlled louvers to open when the outside air temperature reaches a predetermined value and to close when there is no ambient sunlight. The collector operates day and night, the year around, collecting and storing heat.

Gorniak, J.

1978-08-22

8

Solar energy collector system  

Energy Technology Data Exchange (ETDEWEB)

Simple flat plate reflectors, preferably compound of a panel with a reflector surface layer laminated thereto, are pivoted to move with the position of the sun and concentrate additional energy on a solar energy collector panel. The array can take a tented or triangular end view shape for closing to protect reflective surfaces from hail or sandstorm, etc. Also the surfaces are provided with a periodically operable surface cleaner to assure long term efficiency even when remotely positioned as on roof top. Low cost present day computers are programmed to track the sun over its seasonal variations by means of simple mechanisms pivoting the reflector plates. The system is self-energizing by means of batteries charged by solar panels accompanying the system. Solar energy is storable in a self-contained water tank for use at night, etc. And efficient energy conversion is attained by means of a stainless steel pipe length extending into the stored water and thermally coupled outside the tank to a solar heated higher than 100* C. Silicon oil circulated through the solar collector. Thus, vaporization is avoided and an effective lowcost simplified thermal energy conversion is effected.

Dumbeck, R.F.

1982-04-13

9

Solar energy collector  

Energy Technology Data Exchange (ETDEWEB)

A sun tracking solar energy collector assembly having both a longitudinally extending flat plate absorber and a tube absorber spaced from and extending longitudinally generally parallel to the flat plate absorber. In one form a parabolic reflector focuses direct rays of solar radiation on the tube absorber and directs diffused rays of solar radiation onto the plate absorber. In another form a fresnel lens plate focuses direct rays of solar radiation on the tube absorber and flat reflector surfaces direct diffused solar radiation passing through the lens plate onto the plate absorber. In both forms a fluid is first heated as it circulates through passages in the flat plate absorber and then is further heated to a higher temperature as it passes through the tube absorber.

Penney, R.J.

1980-09-02

10

Solar optical energy collector  

Energy Technology Data Exchange (ETDEWEB)

A solar optical energy collector is disclosed having a lens system for concentrating sun beams and a sun beams receiving system for introducing said sun beams being concentrated into a optical-conductor cable. In order to obtain the most effective arrangement of the lens system, said lens system comprises a plurality (N) of Fresnel lenses each formed in the shape of a hexagon, i.e. N=3n(+1) Fresnel lenses are disposed around one Fresnel lens so that each side of the one Fresnel lens positioned in the center of the lens system adjoins to one side of each respective surrounding Fresnel lenses in a concentric-circular relationship, wherein (n) stands for a natural number.

Mori, K.

1983-10-18

11

Solar collectors, energy storage, and materials  

International Nuclear Information System (INIS)

This book covers topics concerning solar collectors, energy storage, and materials, including: modeling of solar collectors and thermal energy storage, optical research and development, collector thermal research, solar ponds, economics, and solar materials

1990-01-01

12

Focusing solar energy collector  

Energy Technology Data Exchange (ETDEWEB)

A collector is described which contains a cylindrical housing with bent mirror side turned towards the optically transparent cover made in the form of a Fresnel lens and tubular radiation receiver arranged in the focus. In order to improve efficiency, the housing in the cross section has the shape of the hyperbola, and the focus which is first in the passage of the rays is superposed with the Fresnel lens focus, and the second with center of gravity of the collector.

Tveryanovich, E.V.; Chumichev, V.B.; Grantsev, K.O.; Korneyeva, N.S.; Strebkov, D.S.

1983-01-01

13

Solar energy collector  

Energy Technology Data Exchange (ETDEWEB)

A solar collector is described having a hollow, pyrimidical-shaped body made of insulation material and a fluid conducting coil of tubing extending around the inside of the body. A plurality of sheets of rigid material support alternate layers of liquid and of lenses which focus sunlight onto the liquid and onto the coils of tubing thereby heating the liquid. The liquid in the coils is connected in series with the liquid supported on the sheets so that liquid can be withdrawn from the ends of the coils and passed through a battery for storing the heat or otherwise supported and stored. The collector also includes an infrared absorber. 12 claims, 10 figures.

Gorniak, J.

1977-06-14

14

Radiant Barriers Save Energy in Buildings  

Science.gov (United States)

Langley Research Center needed to coat the Echo 1 satellite with a fine mist of vaporized metal, and collaborated with industry to create "radiant barrier technology." In 2010, Ryan Garrett learned about a new version of the technology resistant to oxidation and founded RadiaSource in Ogden, Utah, to provide the NASA-derived technology for applications in homes, warehouses, gymnasiums, and agricultural settings.

2014-01-01

15

Solar energy collectors, production method  

Energy Technology Data Exchange (ETDEWEB)

Solar energy collectors, according to invention, use black-pigmented organo-poly-siloxane-elastomere as solar-energy absorbing material. Pipes for heat-exchanging liquid are hollow and 25-80% of the pipes wall-surface consists of trough-like moulds covered with black-pigmented elastomeres. The rest are opposite trough-like moulds covered with ultra-violet-resistant transparent elastomere solidly bound to the black-pigmented elastomeres, preferably organo-poly-siloxane-elastomeres. Solar energy collectors can be produced by producing a tube-bundle from a cross-linkage transparent ultra-violet resistant material on a black-pigmented material, which can be crosslinked to organo-poly-siloxane-elastomere by means of co-extrusion. Afterwards crosslinking takes place by heating or energy-rich radiation.

Gerhardinger, D.; Kudlich, W.; Krohberger, H.; Wimmer, H.

1982-04-29

16

CERES: Clouds and the Earth's Radiant Energy System  

Science.gov (United States)

This brochure gives a brief description of the science research that is being done with data from the Clouds and Earth's Radiant Energy System (CERES) instrument flying onboard NASA's Terra satellite. It also contains information about some of the data products and technical specifications.

1999-04-01

17

Design of energy efficient building with radiant slab cooling  

Science.gov (United States)

Air-conditioning comprises a substantial fraction of commercial building energy use because of compressor-driven refrigeration and fan-driven air circulation. Core regions of large buildings require year-round cooling due to heat gains from people, lights and equipment. Negative environmental impacts include CO2 emissions from electric generation and leakage of ozone-depleting refrigerants. Some argue that radiant cooling simultaneously improves building efficiency and occupant thermal comfort, and that current thermal comfort models fail to reflect occupant experience with radiant thermal control systems. There is little field evidence to test these claims. The University of Calgary's Information and Communications Technology (ICT) Building, is a pioneering radiant slab cooling installation in North America. Thermal comfort and energy performance were evaluated. Measurements included: (1) heating and cooling energy use, (2) electrical energy use for lighting and equipment, and (3) indoor temperatures. Accuracy of a whole building energy simulation model was evaluated with these data. Simulation was then used to compare the radiant slab design with a conventional (variable air volume) system. The radiant system energy performance was found to be poorer mainly due to: (1) simultaneous cooling by the slab and heating by other systems, (2) omission of low-exergy (e.g., groundwater) cooling possible with the high cooling water temperatures possible with radiant slabs and (3) excessive solar gain and conductive heat loss due to the wall and fenestration design. Occupant thermal comfort was evaluated through questionnaires and concurrent measurement of workstation comfort parameters. Analysis of 116 sets of data from 82 occupants showed that occupant assessment was consistent with estimates based on current thermal comfort models. The main thermal comfort improvements were reductions in (1) local discomfort from draft and (2) vertical air temperature stratification. The analysis showed that integrated architectural and mechanical design is required to achieve the potential benefits of radiant slab cooling, including: (1) reduction of peak solar gain via windows through (a) avoiding large window-to-wall ratios and/or (b) exterior shading of windows, (2) use of low-quality cooling sources such as cooling towers and ground water, especially in cold, dry climates, and (3) coordination of system control to avoid simultaneous heating and cooling.

Tian, Zhen

18

Solar energy collector  

Energy Technology Data Exchange (ETDEWEB)

Apparatus is described for collecting, concentrating and absorbing solar rays and transferring solar energy to a heat transfer fluid , including (A) an elongated parabolic reflector having a nadir and a focal plane, (B) the focal plane disposed above the nadir, (C) a focal area in the focal plane, (D) an absorbing means with planar sides disposed at least in part in the focal area above the nadir, (E) a tubular conveyor affixed to an edge of the absorber and disposed above the reflector, and (F) a pair of elongated fluid conducting manifolds each formed of mated upper and lower members said manifolds positioned at opposite ends of the reflector with the ends of said conveyor sealingly positioned and supported in mated recesses disposed along the length of said manifold members, wherein the fluid conducting manifolds support the tubular conveyor at each end of the reflector and conduit a heat transfer fluid to and way from the conveyors.

Niedermeyer, W.

1980-07-29

19

Solar collector  

Energy Technology Data Exchange (ETDEWEB)

The invention concerns a collector for obtaining radiant energy, particularly solar radiation, consisting of a collector plate and pipes connected to it, which have a liquid, particularly water flowing through. The purpose of this invention is to shape the collectors, so that as much radiant energy as possible is converted and taken away by the water flowing through the pipes. This problem is solved by having the pipes arranged on top of the collector plates and having indentations on the collector plates next to the pipes, from which tongues holding the pipes are bent, which are connected to the collector plates on the side of the pipes. This structural device ensures that the heat transfer from the plate to the pipes and from the pipes to the water is better than when the pipes are moulded in the plates. In an advantageous form of the invention reflecting material, e.g. a reflector foil is arranged on the underside of the collector plate in the area of the indentations, which has a surface reflecting radiation on to the pipes.

1980-03-13

20

Combined solar collector and energy storage system  

Science.gov (United States)

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.

Jensen, R. N. (inventor)

1980-01-01

 
 
 
 
21

Solar energy concentrating slat arrangement and collector  

Energy Technology Data Exchange (ETDEWEB)

Disclosed are improved elongated, reflective slat concentrators and elongated multi-conduit/multi-fluid collectors and systems thereof. The reflective slats are generally of rectangular configuration and extending about a curve. In systems utilizing the concentrators, the collector is located above the concentrator, i.e. forwardly of the concentrator relative to the travel of solar energy to the concentrator.

Stark, V.; Genequand, P.

1985-06-04

22

Radiant energy collection and conversion apparatus and method  

Energy Technology Data Exchange (ETDEWEB)

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Hunt, Arlon J. (Oakland, CA)

1982-01-01

23

Radiant barriers in houses: Energy, comfort, and moisture considerations in a northern climate  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to determine the conditions under which radiant barrier utilization in attics is appropriate technology in building construction for a northern climate in Utah. A sample of 12 appropriate houses with radiant barriers were selected using predetermined criteria. Another 12 houses without radiant barriers were selected as a control sample and paired with the first 12 houses using predetermined criteria. The research involved three different types of data and analyses. First, a questionnaire survey was completed by the occupants of the 12 sample houses, with radiant barriers. The survey included such factors as: (1) comfort, (2) energy, and (3) potential increased moisture content as perceived by the occupants. Second, a t-test was used to calculate the statistical comparison of utility usage between the 12 sample houses with radiant barriers and the 12 control houses without radiant barriers. Third, the moisture content of the wood framing above and below the radiant barriers was measured over a three month period during the winter months. Data analysis indicated: (1) occupants did perceive that more comfort resulted from the installation of radiant barriers, (2) occupants did not observe additional moisture artifacts after the installation of radiant barriers, (3) occupants did perceive cost savings from utility benefits resulting from the use of radiant barriers, especially in cooling the houses in summer, (4) there was no significant difference between utility usage of houses with radiant barriers and houses without radiant barriers, (5) the moisture content in the ceiling joists of all 24 houses, except one, had a moisture content measurement less than eight percent, and (6) houses with radiant barriers have higher humidity levels within the living space than houses without radiant barrier installation.

Mendenhall, R.L.

1990-01-01

24

A radiant energy imaging apparatus for examination of a body  

International Nuclear Information System (INIS)

A radiant energy imaging apparatus for obtaining CT scans is described. It employs a rotating unit operative to produce a scanning pencil beam of X-ray radiant energy by use of a mechanical scanning device. This consists of a first collimator which shapes radiation emitted from an X-ray source into a fan-shaped beam of X-rays, and a second collimator comprising a disc-shaped chopper wheel which is rotated through the fan-shaped beam. A single pencil beam is produced and caused to scan through an angle, sufficiently great to embrace a cross section of a body being examined, onto a single detector forming a portion of the rotating unit and located on the side of the body opposite to the X-ray source and mechanical scanning device. In addition to being used as a CT scanner, the system can be used to generate its own localization images and to perform digital radiography on those images and, because of the relative rotation feature, can be employed in this mode of operation to obtain anterior-posterior, lateral or oblique images at any desired angle. (Auth.)

1980-05-19

25

Heating energy measurements of unoccupied single-family houses with attics containing radiant barriers  

Energy Technology Data Exchange (ETDEWEB)

Tests were conducted by Oak Ridge National Laboratory (ORNL) to determine the magnitude of the heating energy savings achieved by installing attic radiant barriers. The radiant barriers used for the test consist of a material with two reflective aluminum surfaces on a kraft paper base. The experiment was conducted in three unoccupied research houses operated by ORNL. Two variations in the installation of radiant barriers were studied. One house was used as the control house (no barrier was installed), while the other two were used to test the two methods for installing the radiant barriers. In one house, the radiant barrier was laid on top of the attic fiberglass batt insulation, and in the other house, the barrier was attached to the underside of the roof trusses. The attics of all three houses were insulated with a kraft-paper-faced R-19 fiberglass batt insulation. The winter test with the radiant barrier showed that the horizontal barrier was able to save space-heating electical energy in both the resistance and heat pump modes amounting to 10.1% and 8.5%, respectively. The roof truss radiant barrier increased consumption by 2.6% in the resistance mode and 4.0% in the heat pump mode. The horizontal orientation of the radiant barrier is the more energy-effective method of installation.

Levins, W.P.; Karnitz, M.A.

1987-01-01

26

Cooling-energy measurements of unoccupied single-family houses with attics containing radiant barriers  

Energy Technology Data Exchange (ETDEWEB)

Tests were conducted by Oak Ridge National Laboratory (ORNL) to determine the magnitude of the energy savings brought about by installing radiant barriers in the attics of single-family houses. The radiant barrier used for this test is a product with two reflective aluminum surfaces on a kraft paper base. The purpose of the radiant barrier is to reduce the radiant heat transfer component impinging on the fiberglass attic insulation. The radiant barrier works as a system in conjunction with an air space and can theoretically block up to 95% of far-infrared radiation heat transfer. The experiment was conducted in three unoccupied research houses that are operated by ORNL. Two variations on the installation of radiant barriers were studied. One house was used as the control house (no barrier was installed), while the other two were used to test the two different methods for installing the radiant barriers. In one house the barrier was laid on top of the attic fiberglass batt insulation, and in the other house, the barrier was attached to the underside of the roof trusses. The attics of all three houses were insulated with kraft-paper-faced R-19 fiberglass batt insulation. The results showed a savings in the cooling loads of 21% when the radiant barrier was laid on top of the attic fiberglass insulation and 13% with the radiant barrier attached to the underside of the roof trusses. The savings in electrical consumption were 17% and 9%, respectively. The electrical consumption data and the cooling load data indicate that the most effective way of installing the foil is to lay it on top of the fiberglass insulation. The radiant barriers reduced the measured peak ceiling heat fluxes by 39% for the case where the barrier was laid on top of the fiberglass insulation. The radiant barrier reduced the integrated heat flows from the attic to the house by approximately 30 to 35% over a 7-day time period.

Levins, W.P.; Karnitz, M.A.

1986-07-01

27

Wide-angle sensor measures radiant heat energy in corrosive atmospheres  

Science.gov (United States)

Ellipsoidal cavity device measures radiant heat energy over wide incident angles in corrosive atmospheres. The instrument consists of a cavity in copper heat sink sealed with sapphire window to protect thermocouple.

1965-01-01

28

Radiant surface combustor  

Energy Technology Data Exchange (ETDEWEB)

A radiant surface combustor is described comprising a porous combustor element in close heat transfer relation with a heat transfer surface for absorbing radiant heat energy from the combustor element.

Carpenter, D.V.; Rackley, R.A.

1982-01-19

29

Complete theoretical treatment of the transmittance ratio ultraviolet/visible spectrophotometric stray radiant energy test method.  

Science.gov (United States)

This paper develops the theoretical basis behind the transmittance ratio test method for determining the relative stray radiant energy level in a double-beam dispersive spectrophotometer so as to allow for the non-transparency of a test solution towards the stray radiant energy for all sample beam-to-reference beam cuvette path length ratios. Non-transparency is defined as the transmittance of the reference beam solution, whose monochromatic absorbance is unity, towards stray radiant energy. The proposed method has the same concentration absorbing sample placed in the beams of the scanning spectrophotometer, the sample-beam cuvette being a known factor longer than the reference-beam cuvette. While scanning towards shorter wavelengths, an apparent differential absorbance Mielenz peak is recorded. An exact formula is derived in this paper relating the relative stray radiant energy level to the Mielenz peak absorbance, to the known cuvette path length ratio, to the observed monochromatic absorbance of the test sample at the Mielenz peak wavelength, and to the sample transmittance towards the stray radiant energy. Sample transmittance towards stray radiant energy cannot be determined experimentally. However, the derived formula only allows the other experimental quantities to tie in together for a single numerically calculated value for the sample-transmittance towards stray radiant energy. The formulae are tedious to derive and cumbersome to handle, but their application is facilitated greatly by a Microsoft Office Excel 2007 spreadsheet. The test method was applied to an ultraviolet-visible (UV/VIS) scanning spectrophotometer at nine wavelengths in the range 713 > lambda (nm) >; 649 for a sample beam-to-reference beam cuvette path length ratio of 10 mm/5 mm and using blue food dye (E123) as the test material. Sample transparency to stray radiant energy fluctuated in wavelength between 0.819 and 0.948, while the relative stray radiant energy level fluctuated between 1.283 x 10(-3) and 2.516 x 10(-3). The investigation was repeated at 665.6 nm for all fifteen sample beam-to-reference beam cuvette path length ratios, which it was possible to establish using combinations of quartz-glass cuvettes with path lengths of 100, 50, 20, 10, 5, 2, and 1 mm. The sample transparency to stray radiant energy at 665.6 nm was 0.95 +/- 0.5, while the relative stray radiant energy was (1.5 +/- 0.33) x 10(-3). PMID:19843363

Fleming, Paddy

2009-10-01

30

The effects of radiant barriers on ceiling heat flux and energy usage  

Energy Technology Data Exchange (ETDEWEB)

In this study a gable ventilation system was installed in an experimental facility to determine the effects of ventilation type on radiant barrier performance. The radiant barriers were installed horizontally above the ceiling insulation. The measured performance was then compared to documented results for a ridge and soffit ventilation system. This study experimentally determined the effects of radiant barriers on ceiling heat loss in cathedral ceiling homes during the winter heating season. A normalization procedure was used to allow short term, clear sky measurements from different days of similar weather to be used to determine radiant barrier performance. The procedure normalized for weather variations of ambient temperature and solar insolation under clear sky conditions to isolate the effects of radiant barriers. In these studies radiant barriers were examined for energy conservation, load shifting and demand reduction characteristics. A thermal model to predict shingle temperature in cathedral ceiling homes was also developed. The experimental results show that radiant barriers are not as effective in homes with a gable ventilation system as compared to homes with a ridge and soffit system. This result is primarily due to increased air flow rates with a ridge and soffit ventilation system. For the gable ventilation system the radiant barriers reduced the peak heat flux by 20% and provided an energy conservation of 4.1%. However, it was found that better load shifting characteristics were present. Radiant barriers conserved energy in a winter study of cathedral ceilings by actually reducing the total heat loss from the ceiling by 40% for peak heating days. The shingle temperature model was validated by comparing ceiling heat flux predictions using actual measured temperatures and modeled temperatures.

McGovern, K.T.; Beasley, D.E. [Clemson Univ., SC (United States). Dept. of Mechanical Engineering

1995-12-31

31

Implementation of a radiant heating and cooling model into an integrated building energy analysis program  

Energy Technology Data Exchange (ETDEWEB)

The ability to fairly compare the energy efficiency of radiant heating and cooling systems to conventional forced-air systems has been a long-standing goal of the engineering design community. Such a comparison can only be made, however, through the fundamental analysis of the transient nature of the radiant system, the combined radiative and convective heat transfer from the radiant system, and the resulting thermal environment produced by both space-conditioning systems. A simulation tool that incorporates all of these characteristics has been developed. The model uses a derivative of conduction transfer functions that includes the effects of embedded sources or sinks to accurately account for the transient heat conduction in the radiant system. This model has been implemented into a well-know heat-balance-based energy analysis program and takes into account both the radiative and convective heat transfer at the surface of the radiant system. Due to the fact that the energy analysis program has three established thermal comfort models built into it, it is possible to compare energy consumption on the basis of resulting thermal comfort parameters rather than simply mean air temperature. Additionally, since interior surface temperatures are readily available, the model can evaluate radiant cooling systems for condensation potential and this can be used to indicate when a hybrid system is needed. This paper describes the implementation of the radiant heating and cooling model and presents an example comparing the energy consumption of a radiant system and a conventional forced-air system that provide equal levels of comfort.

Strand, R.K.; Pedersen, C.O. [Univ. of Illinois, Urbana, IL (United States). Dept. of Mechanical and Industrial Engineering

1997-12-31

32

Solar collector apparatus having increased energy rejection during stagnation  

Science.gov (United States)

The disclosure relates to an active solar collector having increased energy rejection during stagnation. The collector's glazing is brought into substantial contact with absorber during stagnation to increase re-emittance and thereby to maintain lower temperatures when the collector is not in operation.

Moore, Stanley W. (Los Alamos, NM)

1983-07-12

33

Efficacy of solar energy collectors made of aluminum  

Energy Technology Data Exchange (ETDEWEB)

An analysis is made of the energy intensity of making aluminum parts of SALK type collectors manufactured by the SNP enterprise (CSSR). By comparing the generated energy and energy intensity, the energy compensation is determined. Comparison of the outlays per unit of rated power indicated that the outlays for the system with SALK type collectors are 70% lower than with the use of collectors made of steel.

Fiser, M.; Baloun, J.

1983-01-01

34

Porous radiant burners having increased radiant output  

Energy Technology Data Exchange (ETDEWEB)

Means and methods for enhancing the output of radiant energy from a porous radiant burner by minimizing the scattering and increasing the adsorption, and thus emission of such energy by the use of randomly dispersed ceramic fibers of sub-micron diameter in the fabrication of ceramic fiber matrix burners and for use therein.

Tong, Timothy W. (Tempe, AZ); Sathe, Sanjeev B. (Tempe, AZ); Peck, Robert E. (Tempe, AZ)

1990-01-01

35

Solar energy system and solar heat collector  

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a solar energy system comprising a collector consisting of a sloping space exposed to solar light for a heat transporting medium performing a primary circulation, which is thermally coupled by the downward run with a working medium circuit. An object of the invention is to design a solar energy system in a manner such that in contrast to the conventional system no control or safety apparatus is required, since solely natural, physical mechanisms are used so that a self-controlling operation is obtained, as a result of which the risk of disturbances and standstill is considerably reduced and the intrinsic safety is enhanced. The above-mentioned purposes are, in general, achieved by means of a system set forth in the preamble, the primary circulation of which takes place in a vessel partly filled with fluid and partly with the vapor thereof and operating as a heat pipe. The invention further provides a solar heat collector, the active surface of which is divided into cells bounded by upright ribs. Owing to the provision of such cells the dissipation of heat by convection due to wind brushing past can be reduced to negligible proportions.

Bertels, A. W. B.

1985-07-09

36

Collector means for solar energy collecting system  

Energy Technology Data Exchange (ETDEWEB)

In accordance with the present invention, an improved collector means for a solar energy collector system having an absorber plate and a glazing panel spaced from at least one side of the absorber plate in which a cap means is coupled to and extends along one edge of the absorber plate and a depending leg extends over the complimentary edge of the glazing panel, the cap means having formed therein at least one air channel conforming in shape to the cross-sectional shape of the cap means and having air inlet means adjacent the bottom of a leg of the cap means in communication with the channel and an air outlet means adjacent the top of the cap means and in communication with the channel and adapted to permit currents of cooling air to pass therethrough from the inlet to the outlet, thereby maintaining said complimentary edge of the glazing panel relatively cool. In a preferred embodiment, the improved collector means is mounted edgewise adjacent the bottom of a parabolic trough-type reflector means and has a glazing panel on both exposed sides thereof. In accordance with a further embodiment of the present invention, the glazing panel is a flexible sheet material detachably coupled adjacent one edge of the absorber plate and the other end of a glazing material comprises a supply roll mounted adjacent the other edge of the absorber plate, whereby a fresh surface of glazing sheet material can be withdrawn from the roll and mounted parallel to the absorber plate as needed. Preferably, the roll of glazing sheet material is spring loaded so as to maintain the material taut, for example by a window shade-type roll means.

Nikkel, R.D.; L' Esperance, P.M.

1984-08-14

37

Energy, cost, and CO 2 emission comparison between radiant wall panel systems and radiator systems  

CERN Document Server

The main goal of this paper is to evaluate the possibility of application or replacement of radiators with low-temperature radiant panels. This paper shows the comparison results of operations of 4 space heating systems: the low-temperature radiant panel system without any additional thermal insulation of external walls (PH-WOI), the low-temperature radiant panel system with additional thermal insulation of external walls (PH-WI), the radiator system without any additional thermal insulation of external walls (the classical heating system) (RH-WOI), and the radiator system with additional thermal insulation of external walls (RH-WI). The operation of each system is simulated by software EnergyPlus. The investigation shows that the PH-WI gives the best results. The RH-WOI has the largest energy consumption, and the largest pollutant emission. However, the PH-WI requires the highest investment.

Boji?, Milorad; Mileti?, Marko; Maleševi?, Jovan; Boyer, Harry

2012-01-01

38

Solar energy collector and method of making same  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method of making a solar energy collecting device which includes glass absorbing means for absorbing radiant energy and transferring the energy to a heat transfer fluid carried thereby, and insulating means for passing therethrough radiant energy while insulating the absorbing means from an external environment. The method consists of melting a metallic substance to form molten metal, spraying the molten metal on the glass absorbing means by use of a stream of pressurized gas so as to fuse a metallic layer thereon, blackening the metallic layer, and hermetically sealing together the glass absorbing means and the insulating means so as to form an insulating chamber therebetween, whereby the absorbing means absorbs, when the collecting device is operational, solar energy at a level of at least 70% and passes the same to the heat transfer fluid while emitting no more than 5% energy in the infrared range. A method of making a solar energy concentrator for use with solar absorbing means for absorbing solar energy and for transferring the solar energy to a heat transfer fluid carried thereby. The concentrator includes a solar energy concentrating means for directing radiant energy onto the absorbing means. The concentrating means is made by the steps of: forming a transparent glass member in a shape so that, when disposed about the absorbing means, an inner surface of the transparent member faces and is adapted to direct radiant energy onto the absorbing means, and melting a metallic substance to form molten metal, spraying the molten metal on an outer surface of the transparent glass member by use of a stream of pressurized gas so as to fuse thereon a thin metallic layer thereby to form a smooth, highly reflective concentrator for directing radiant energy onto the absorbing means. This patent also describes a solar energy collecting devices.

Deakin, D.

1986-04-01

39

ENHANCING THE STABILITY OF THE BIRDS TO PULLOROZU INFLUENCE OF RADIANT ENERGY ????????? ???????????? ????? ? ????????? ???????????? ???????? ???????  

Directory of Open Access Journals (Sweden)

Full Text Available The article presents the research materials of viability of broiler chickens in bad conditions with pullorosis when exposed embryos and day-old chicks to radiant energy, the results of the content and lysozyme activity, bactericidal activity of serum lysozyme in relation to the test culture, the overall viability and survival of the birds in pullorosis in bad conditions

Tokhtiev T. A.

2013-09-01

40

An evaluation of thermal comfort and energy consumption for a surface-mounted ceiling radiant panel heating system  

Energy Technology Data Exchange (ETDEWEB)

A review of literature revealed little relevant empirical evidence for energy savings and thermal comfort associated with ceiling, surface-mounted radiant heating systems. Empirical studies used to discuss the energy and thermal comfort performance of radiant heating systems made little or no distinction among the various types of radiant heating systems. Since ceiling, surface-mounted radiant panels-in contrast to other radiant systems-are fast-acting and deliver a much higher proportion of their output as radiant heat, they can have a substantial impact on both energy and thermal comfort performance. Testing the energy and thermal comfort performance in an occupied home could serve to expand the base of information on which discussions of various heating strategies are based. A surface-mounted, ceiling radiant heating system, an air-to-air heat pump system, and a monitoring data-acquisition system were installed in an occupied research home. Information on thermal comfort and energy consumption for alternating operation of the two heating systems was collected for approximately half of a heating season. This allowed a comparison of the radiant system and the more conventional air-to-air heat pump system. Also, data on energy consumption from a zoned electric baseboard heating system previously installed in the same house were available for comparison. Fast-acting radiant heating systems that can recover quickly from setback and target the delivery of heat to objects and occupants have a significantly reduced installed capacity in comparison to more conventional heating systems. In this study, for the same outdoor design conditions, the installed capacity of the radiant system was 2.5 times less than the electric baseboard system and two times less than that of the heat pump system.

Yost, P.A.; Barbour, C.E. [NAHB Research Center, Inc., Upper Marlboro, MD (United States); Watson, R.

1995-08-01

 
 
 
 
41

Integrated Solar Energy Collector Final Summary Report.  

Science.gov (United States)

A flat plate solar collector originated by Los Alamos Scientific Laboratories was studied for mass production manufacturing techniques, design improvements, costs, and architectural integration into arrays for residences and light commercial buildings. Th...

R. B. Toenjes

1975-01-01

42

Molecules, Water, and Radiant Energy: New Clues for the Origin of Life  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We here examine the putative first step in the origin of life: the coalescence of dispersed molecules into a more condensed, organized state. Fresh evidence implies that the driving energy for this coalescence may come in a manner more direct than previously thought. The sun’s radiant energy separates charge in water, and this free charge demonstrably induces condensation. This condensation mechanism puts water as a central protagonist in life rather than as an incidental participant, and t...

Pollack, Gerald H.; Figueroa, Xavier; Zhao, Qing

2009-01-01

43

MATERIALS PROBLEMS IN EVACUATED SOLAR ENERGY COLLECTORS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An investigation of the absorptance and emittance of selective absorbing surfaces based on reactively sputtered metal carbide films is described. These surfaces exhibit good stability at 300 °C in vacuum. Novel techniques have been developed for evaluation of absorptance and temperature dependent emittance of selective surfaces incorporated in assembled collectors. Thermal conduction losses in evacuated collectors due to low pressures of H2O, N2, He, Ar, H2 and CO have been determined. Metho...

1981-01-01

44

Radiant energy absorption studies for laser propulsion. [gas dynamics  

Science.gov (United States)

A study of the energy absorption mechanisms and fluid dynamic considerations for efficient conversion of high power laser radiation into a high velocity flow is presented. The objectives of the study are: (1) to determine the most effective absorption mechanisms for converting laser radiation into translational energy, and (2) to examine the requirements for transfer of the absorbed energy into a steady flow which is stable to disturbances in the absorption zone. A review of inverse Bremsstrahlung, molecular and particulate absorption mechanisms is considered and the steady flow and stability considerations for conversion of the laser power to a high velocity flow in a nozzle configuration is calculated. A quasi-one-dimensional flow through a nozzle was formulated under the assumptions of perfect gas.

Caledonia, G. E.; Wu, P. K. S.; Pirri, A. N.

1975-01-01

45

Molecules, Water, and Radiant Energy: New Clues for the Origin of Life  

Directory of Open Access Journals (Sweden)

Full Text Available We here examine the putative first step in the origin of life: the coalescence of dispersed molecules into a more condensed, organized state. Fresh evidence implies that the driving energy for this coalescence may come in a manner more direct than previously thought. The sun’s radiant energy separates charge in water, and this free charge demonstrably induces condensation. This condensation mechanism puts water as a central protagonist in life rather than as an incidental participant, and thereby helps explain why life requires water.

Qing Zhao

2009-03-01

46

A Non-Tracking Solar Energy Collector System.  

Science.gov (United States)

A solar energy collector system is characterized by an improved concentrator for directing incident rays of solar energy on parallel strip-like segments of a flat-plate receiver. A plurality of individually mounted reflector modules of a common asymmetric...

M. K. Selcuk

1977-01-01

47

Bi-radiant oven: a low-energy oven system. Volume I. Development and assessment  

Energy Technology Data Exchange (ETDEWEB)

The Bi-Radiant Oven system has three important features which provide improved performance. First, the cavity walls are highly reflective rather than absorptive thereby allowing these surfaces to operate at cooler temperatures. Second, the heating elements, similar in construction to those in a conventional oven, but operating at much lower temperatures, provide a prescribed, balanced radiant flux to the top and bottom surfaces of the food product. And third, the baking and roasting utensil has a highly absorptive finish. Instrumentation and methods of measurements have been developed for obtaining the important oven and food parameters during baking: wall, oven air, food and element temperatures; food mass loss rate; irradiance distribution; and convection heat flux. Observations on an experimental oven are presented and discussed. Thermal models relating the irradiance distribution to oven parameters have been compared with measurements using a new heat flux gage developed for the project. Using the DOE recommended test procedures, oven efficiencies of 20 to 23% have been measured. The heating requirements have been determined for seven food types: biscuits, meat loaf, baked foods, apple crisp, cornbread, macaroni and cheese casserole, and cheese souffle. Comparison of energy use with a conventional electric oven shows that energy savings greater than 50% can be realized. Detailed energy balances have been performed on two foods - beef roasts and yellow cake. Consideration of consumer acceptability of this new oven concept have been addressed.

DeWitt, D.P.; Peart, M.V.

1980-04-01

48

Standardized performance tests of collectors of solar thermal energy: Prototype moderately concentrating grooved collectors  

Science.gov (United States)

Prototypes of moderately concentrating grooved collectors were tested with a solar simulator for varying inlet temperature, flux level, and incident angle. Collector performance is correlated in terms of inlet temperature and flux level.

1976-01-01

49

Energy, cost, and CO 2 emission comparison between radiant wall panel systems and radiator systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The main goal of this paper is to evaluate the possibility of application or replacement of radiators with low-temperature radiant panels. This paper shows the comparison results of operations of 4 space heating systems: the low-temperature radiant panel system without any additional thermal insulation of external walls (PH-WOI), the low-temperature radiant panel system with additional thermal insulation of external walls (PH-WI), the radiator system without any additional thermal insulation ...

Bojic?, Milorad; Cvetkovic?, Dragan; Miletic?, Marko; Males?evic?, Jovan; Boyer, Harry

2012-01-01

50

Radiant transport function for radiant heat transfer problems in buildings and urban spaces  

Energy Technology Data Exchange (ETDEWEB)

Radiant transport functions encountered in buildings and urban spaces are complex and diverse and are especially different depending on the inside of buildings because of the existence of atmospheric radiation in the outdoors and transparency conditions in rooms. A radiant transport function is proposed in order to overcome such difficulties and to obtain a systematic understanding of the entire system. It is defined as the response at any point and in any direction in enclosure for the excitation of the radiant energy emission at a point and direction by the Dirac delta function. The radiant transport function indicates the characteristics of the radiant energy transferred in an enclosure. Therefore, it is effective for understanding the behavior of radiant energy when the radiant transport function is obtained in buildings and urban spaces. The radiant energy is determined simply integrating the function with the emissive power thus avoiding the otherwise tedious calculations necessary to solve the integral equation for a radiant transfer problem.

Nakamura, Y. (Dept. of Architecture, Kyoto Univ. (JP))

1989-05-01

51

Modeling the spatial distribution of the volumic radiant energy and absorbed dose of radiation in the DNA structure under accelerated heavy ions  

International Nuclear Information System (INIS)

Model approaches are developed to the description of the mechanism of the formation of different types of atomic-level DNA lesions under accelerated heavy ions. The radial distribution of volumic radiant energy and the absorbed dose are calculated in accelerated heavy ions. The radial distribution of volumic radiant energy and the absorbed dose are calculated in accelerated 4He, 12C, and 40Ar ion tracks in the energy range of 3-20 MeV/nucleon. The spatial location of the atoms of an adenine-thymine nucleotide pair is compared with the calculated radial dose and volumic radiant energy distribution

2011-01-01

52

Radiant heaters  

Energy Technology Data Exchange (ETDEWEB)

A radiant heater is described comprising, A. heat reflective housing means, B. the heat reflective housing means including, i. top reflector surface means having, a first reflector section, and a second reflector section, ii. the first reflector section and the second reflector section disposed at a predetermined angle to each other to concentrate the strength of the heat radiating from the heat reflective housing means, and iii. first and second side reflector surfaces and first and second end reflector surfaces operatively connected to the lower section of the top reflector surface means and depending in a range from 6 cm to about 1.1 meters, and C. radiant heating means connected in the top reflector surface means of the heat reflective housing means.

Jones, D.M.; Maund, J.K.

1987-06-30

53

Building Space Heating with a Solar-Assisted Heat Pump Using Roof-Integrated Solar Collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A solar assisted heat pump (SAHP) system was designed by using a roof-integrated solar collector as the evaporator, and then it was demonstrated to provide space heating for a villa in Tianjin, China. A building energy simulation tool was used to predict the space heating load and a three dimensional theoretical model was established to analyze the heat collection performance of the solar roof collector. A floor radiant heating unit was used to decrease the energy demand. The measurement resu...

2011-01-01

54

Heat collector  

Science.gov (United States)

A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

Merrigan, Michael A. (Santa Cruz, NM)

1984-01-01

55

Two-axis movable concentrating solar energy collector  

Science.gov (United States)

Proposed solar-tracker collector assembly with boiler in fixed position, allows use of hard line connections, capable of withstanding optimum high temperature fluid flow. System thereby eliminates need for flexible or slip connection previously used with solar collector systems.

Perkins, G. S.

1977-01-01

56

Point response function of the Clouds and Earth Radiant Energy System scanning radiometer  

Science.gov (United States)

An overview of work related to the point response function (PRF) of the Clouds and Earth Radiant Energy System (CERES) scanning radiometer is presented. The aspects of the CERES design that affect the PRF are described, and then the design of the PRF is explained. The PRF was designed by shaping the field of view so as to minimize the blur plus alias errors of the radiance field reconstructed from the CERES measurements. The design is conducted in the Fourier domain. The PRF can then be computed by transforming the resulting transfer function to the physical domain. Alternatively, the PRF can be computed in the physical plane. The PRF of each model of the CERES instrument has been tested in the Radiation Calibration Facility by use of a PRF source and compared well with prediction. CERES instruments are aboard the Terra, Aqua, and Suomi-NPP spacecraft. In orbit, lunar observations are used to validate the PRF. These results showed nominal performance except for the longwave window channel of flight model 2, for which a region of anomalously high sensitivity was found.

Louis Smith, G.; Daniels, Janet L.; Priestley, Kory J.; Thomas, Susan

2014-01-01

57

Overall energy, exergy and carbon credit analysis by different type of hybrid photovoltaic thermal air collectors  

International Nuclear Information System (INIS)

Highlights: ? Comparative study of PVT air collectors. ? CO2 analysis of all type of PVT air collectors. ? Study of thermal energy, exergy gain and exergy efficiency. ? Exergy efficiency of unglazed hybrid PVT tiles air collector is most efficient. - Abstract: In this paper, comparative analysis of different type of photovoltaic thermal (PVT) air collector namely: (i) unglazed hybrid PVT tiles, (ii) glazed hybrid PVT tiles and (iii) conventional hybrid PVT air collectors have been carried out for the composite climate of Srinagar (India). The comparative study has been carried out in terms of overall thermal energy and exergy gain, exergy efficiency and carbon credit earned by different type of hybrid PVT air collectors. It has been observed that overall annual thermal energy and exergy gain of unglazed hybrid PVT tiles air collector is higher by 27% and 29.3% respectively as compared to glazed hybrid PVT tiles air collector and by 61% and 59.8% respectively as compared to conventional hybrid PVT air collector. It has also been observed that overall annual exergy efficiency of unglazed and glazed hybrid PVT tiles air collector is higher by 9.6% and 53.8% respectively as compared to conventional hybrid PVT air collector. On the basis of comparative study, it has been concluded that CO2 emission reduction per annum on the basis of overall thermal energy gain of unglazed and glazed hybrid PVT tiles air collector is higher by 62.3% and 27.7% respectively as compared to conventional hybrid PVT air collector and on the basis of overall exergy gain it is 59.7% and 22.7%.

2013-01-01

58

Low temperature desalination using solar collectors augmented by thermal energy storage  

International Nuclear Information System (INIS)

Highlights: ? A new low temperature desalination process using solar collectors was investigated. ? A thermal energy storage tank (TES) was included for continuous process operation. ? Solar collector area and TES volumes were optimized by theoretical simulations. ? Economic analysis for the entire process was compared with and without TES tank. ? Energy and emission payback periods for the solar collector system were reported. -- Abstract: A low temperature desalination process capable of producing 100 L/d freshwater was designed to utilize solar energy harvested from flat plate solar collectors. Since solar insolation is intermittent, a thermal energy storage system was incorporated to run the desalination process round the clock. The requirements for solar collector area as well as thermal energy storage volume were estimated based on the variations in solar insolation. Results from this theoretical study confirm that thermal energy storage is a useful component of the system for conserving thermal energy to meet the energy demand when direct solar energy resource is not available. Thermodynamic advantages of the low temperature desalination using thermal energy storage, as well as energy and environmental emissions payback period of the system powered by flat plate solar collectors are presented. It has been determined that a solar collector area of 18 m2 with a thermal energy storage volume of 3 m3 is adequate to produce 100 L/d of freshwater round the clock considering fluctuations in the weather conditions. An economic analysis on the desalination system with thermal energy storage is also presented.

2012-03-01

59

Automated Job Controller for Clouds and the Earth's Radiant Energy System (CERES) Production Processing  

Science.gov (United States)

Clouds and the Earth's Radiant Energy System (CERES) is one of NASA's highest priority Earth Observing System (EOS) scientific instruments. The CERES science team will integrate data from the CERES Flight Model 5 (FM5) on the NPOESS Preparatory Project (NPP) in addition to the four CERES scanning instrument on Terra and Aqua. The CERES production system consists of over 75 Product Generation Executives (PGEs) maintained by twelve subsystem groups. The processing chain fuses CERES instrument observations with data from 19 other unique sources. The addition of FM5 to over 22 instrument years of data to be reprocessed from flight models 1-4 creates a need for an optimized production processing approach. This poster discusses a new approach, using JBoss and Perl to manage job scheduling and interdependencies between PGEs and external data sources. The new optimized approach uses JBoss to serve handler servlets which regulate PGE-level job interdependencies and job completion notifications. Additional servlets are used to regulate all job submissions from the handlers and to interact with the operator. Perl submission scripts are used to build Process Control Files and to interact directly with the operating system and cluster scheduler. The result is a reduced burden on the operator by algorithmically enforcing a set of rules that determine the optimal time to produce data products with the highest integrity. These rules are designed on a per PGE basis and periodically change. This design provides the means to dynamically update PGE rules at run time and increases the processing throughput by using an event driven controller. The immediate notification of a PGE's completion (an event) allows successor PGEs to launch at the proper time with minimal start up latency, thereby increasing computer system utilization.

Gleason, J. L.; Hillyer, T. N.

2011-12-01

60

Modeling the spatial distribution of the volumic radiant energy and absorbed dose of radiation in the DNA structure under accelerated heavy ions  

International Nuclear Information System (INIS)

Model approaches are developed to the description of the mechanism of the formation of different types of atomic-level DNA lesions under accelerated heavy ions. The radial distribution of volumic radiant energy and the absorbed dose are calculated in accelerated 4He, 12C, and 40Ar ion tracks in the energy range of 3-20 MeV/nucleon. The spatial location of the atoms of an adenine-thymine nucleotide pair is compared with the calculated radial dose and volumic radiant energy distribution

2012-01-01

 
 
 
 
61

Use of high efficiency radiant burners can save energy and/or improve product quality  

Energy Technology Data Exchange (ETDEWEB)

Infrared (IR) heating has several advantages to convective heat transfer. Porous radiant burners are typically applied to improve productivity, process efficiency and product quality or in order to reduce operating costs, emissions and required space for process equipment. This paper includes a general description of gas-fired IR heating as well as recent developments in burner technology and ongoing research activities. The new burner designs include ECN`s ceramic multi-layer and multi-step burners, coating of ceramic burners in order to match absorption characteristics of typical products and high temperature surface burners with combustion air preheating. (au)

Myken, A.N.; Rasmussen, N.B.K. [Danish Gas Technology Centre (Denmark); Drift, B. van der [Netherlands Energy Reserch Foundation (Netherlands)

1997-11-01

62

Development of ice storage radiant cooling system. Part 2. Electricity consumption and charge; Kori chikunetsushiki hosha reibo system no kaihatsu. 2. Energy shohi tokusei to running cost  

Energy Technology Data Exchange (ETDEWEB)

A model office which introduced the ice storage radiant cooling system was set up, and an effect of load leveling, energy saving, and a running cost of the building were evaluated. A 24-hour simulation of heat loads and power consumption was conducted relating to a summer peak day and a winter peak day assumed in summer and winter, and average days in each month, in order to calculate the maximum peak power demand in summer, the annual power consumption, and annual power rates. Assessment was made in comparison between the radiant system and convective system, and between with and without ice storage in each system. In the case of ice storage, the radiant system can make the maximum peak power demand in summer and the annual power consumption the same as the convective system or a little less than that in the convective system. On the other hand, in the case of no ice storage, the radiant system increases the maximum peak power demand in summer and the annual power consumption by around 10% over the convective system. The radiant system can reduce the maximum peak power in summer by 34%, the annual power consumption by 10%, and the annual power rate by 30% in the case of ice storage as compared with the case of no ice storage. 13 refs., 9 figs., 14 tabs.

Nakano, Y.; Miyanaga, T.; Onuma, T. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1997-05-01

63

16 CFR 1209.6 - Test procedures for critical radiant flux.  

Science.gov (United States)

...fueled radiant heat energy panel or equivalent...generates a radiant energy flux distribution...level position. The free, or air access...from the radiant energy source. The radiant...to note that the zero reference point on the dummy...

2010-01-01

64

High temperature air combustion. Evaluation of energy saving and NO{sub x} reduction in heat treatment furnaces equipped with radiant tube HiTAC burners. Final report  

Energy Technology Data Exchange (ETDEWEB)

The report presents results of experiments carried out between December 2002 and March 2003 in KTH, Energy and Furnace Technology Division, Stockholm. 30 tests were performed in order to compare the thermal performance of two different burning systems: recuperative and regenerative and their influence on the Radiant-tube at different operating conditions. Measurement results reveal that the temperature profile along the tube was more uniform when the regenerative system was used. Although, the preheated air temperature used for combustion was much higher in the case of regenerative system, the NO{sub x} emission was noticed to be almost the same in both cases. However, the pressure drop across the system was 10 times higher using regenerative system. In order to predict the benefits of the use of the regenerative system, calculations were being carried out. The results of these calculations show that the efficiency of the regenerative system can be up to 30 % higher than that of the recuperative system. The predicted annual saving can be more than 85,000 SEK per year assuming 8,760 operating hours if the burner operates at high thermal capacity and process temperature. Moreover, this theoretical analysis shows also that the maximum temperature of the Radiant-tube can be lower in the case of regenerative system of up to 75 deg C for the same thermal loading. Replacement of electrical resistant elements by radiant tubes that is change from electrical heating to gas fired radiant tubes in the same furnace can save 40% of primary fuel what is equivalent to 40% reduction in CO{sub 2} emission. Work performed was disseminated to industry by means of technical presentations and publications listed in reference list. Some interest was also generated in car manufacturing industry where the HiTAC and radiant tubes burners can be also widely applied.

Blasiak, Wlodzimierz; Szewczyk, Dariusz; Rafidi, Nabil; Jewartowski, Marcin; Goraj, Rafal [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Materials Science and Engineering

2004-05-01

65

A method for calculating the radiant energy incident on a vapor generator in a solar power station  

Science.gov (United States)

An algorithm is developed for calculating the distribution of radiant fluxes along the perimeter of a solar vapor generator (SVG), the mean value of the utilization coefficient of the mirror surface, and the total value of radiant fluxes on the SVG in the course of a day. The method is used to calculate the aforementioned parameters for a tower-type solar power station located in the Crimea for the months of June, September, and December.

Batmunkh, S.

66

Ground Calibrations of the Clouds and the Earth's Radiant Energy System (CERES) Tropical Rainfall Measuring Mission Spacecraft Thermistor Bolometers  

Science.gov (United States)

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometers will measure earth-reflected solar and earth-emmitted,longwave radiances, at the top-of-the-atmosphere. The measurements are performed in the broadband shortwave (0.3-5.0 micron) and longwave (5.0 - >100 micron) spectral regions as well as in the 8 -12 micron water vapor window over geographical footprints as small as 10 kilometers at the nadir. The CERES measurements are designed to improve our knowledge of the earth's natural climate processes, in particular those related to clouds, and man's impact upon climate as indicated by atmospheric temperature. November 1997, the first set of CERES bolometers is scheduled for launch on the Tropical Rainfall Measuring Mission (TRMM) Spacecraft. The CERES bolometers were calibrated radiometrically in a vacuum ground facility using absolute reference sources, tied to the International Temperature Scale of 1990. Accurate bolometer calibrations are dependent upon the derivations of the radiances from the spectral properties [reflectance, transmittance, emittance, etc.] of both the sources and bolometers. In this paper, the overall calibration approaches are discussed for the longwave and shortwave calibrations. The spectral responses for the TRMM bolometer units are presented and applied to the bolometer ground calibrations in order to determine pre-launch calibration gains.

Lee, Robert B., III; Smith, G. Lou; Barkstrom, Bruce R.; Priestley, Kory J.; Thomas, Susan; Paden, Jack; Pandey, Direndra K.; Thornhill, K. Lee; Bolden, William C.; Wilson, Robert S.

1997-01-01

67

Analysis, Design, Fabrication, and Testing of Moderately Concentrating Solar Energy Collectors. Semiannual Progress Report, June--November 1976.  

Science.gov (United States)

The overall object of the proposed work is to aid in the development of low-cost, moderately high temperature, solar energy collectors. This is to be achieved by moderate concentration in a groove-like geometry. Previously, a class of solar collectors con...

J. R. Howell R. B. Bannerot

1976-01-01

68

Radiant burner technology  

Energy Technology Data Exchange (ETDEWEB)

GRI's radiant burner research aims to provide equipment for new high temperature processing applications and to increase productivity of existing furnaces, while lowering operating and capital costs. In parallel projects at Eclipse, Inc. and Pyronics, Inc. ceramic materials are being developed to extend the capabilities of radiant tube burner systems. A silicon-silicon carbide material developed by INEX, Inc. allows radiant tubes to operate at higher temperatures and with better thermal shock resistance. Research is underway to advance surface combustor technology. Hi-Tech Ceramics, Inc. and the Center for Advanced Materials are developing reticulated ceramics. Eclipse Combustion is developing a high efficiency radiant burner with improved combustion heat release.

1991-08-01

69

Spectral Characterizations of the Clouds and the Earth's Radiant Energy System (CERES) Thermistor Bolometers using Fourier Transform Spectrometer (FTS) Techniques  

Science.gov (United States)

Fourier Transform Spectrometer (FTS) techniques are being used to characterize the relative spectral response, or sensitivity, of scanning thermistor bolometers in the infrared (IR) region (2 - >= 100-micrometers). The bolometers are being used in the Clouds and the Earth's Radiant Energy System (CERES) program. The CERES measurements are designed to provide precise, long term monitoring of the Earth's atmospheric radiation energy budget. The CERES instrument houses three bolometric radiometers, a total wavelength (0.3- >= 150-micrometers) sensor, a shortwave (0.3-5-micrometers) sensor, and an atmospheric window (8-12-micrometers) sensor. Accurate spectral characterization is necessary for determining filtered radiances for longwave radiometric calibrations. The CERES bolometers spectral response's are measured in the TRW FTS Vacuum Chamber Facility (FTS - VCF), which uses a FTS as the source and a cavity pyroelectric trap detector as the reference. The CERES bolometers and the cavity detector are contained in a vacuum chamber, while the FTS source is housed in a GN2 purged chamber. Due to the thermal time constant of the CERES bolometers, the FTS must be operated in a step mode. Data are acquired in 6 IR spectral bands covering the entire longwave IR region. In this paper, the TRW spectral calibration facility design and data measurement techniques are described. Two approaches are presented which convert the total channel FTS data into the final CERES spectral characterizations, producing the same calibration coefficients (within 0.1 percent). The resulting spectral response curves are shown, along with error sources in the two procedures. Finally, the impact of each spectral response curve on CERES data validation will be examined through analysis of filtered radiance values from various typical scene types.

Thornhill, K. Lee; Bitting, Herbert; Lee, Robert B., III; Paden, Jack; Pandey, Dhirendra K.; Priestley, Kory J.; Thomas, Susan; Wilson, Robert S.

1998-01-01

70

Potential Use of Radiant Walls to Transfer Energy Between two Building Zones  

DEFF Research Database (Denmark)

Due to a reduced energy demand in low energy buildings, low temperature heating and high temperature cooling can be used to control thermal comfort. Nevertheless, highly varying heat loads due to solar radiation can create sometimes an imbalanced energy demand inside the building. Instead of being considered as a disturbance, this asymmetry can be used as a heat source for another zone of the building. By means of computer simulations, the possibility of shifting the energy demand between two office rooms with different thermal loads has been studied. Due to the small temperature difference between the two zones, capillary tubes embedded in the surface of walls are used to exchange heat from a south-facing room to a north-facing room. In addition to having a better indoor climate, the total heating and cooling consumption decreases when running the system. A comparison has also been performed with a system exchanging room air directly.

Le Dreau, Jerome; Heiselberg, Per

2011-01-01

71

Direct calculation of mean radiant temperature using radiant intensities  

Energy Technology Data Exchange (ETDEWEB)

This paper develops and compares a new method for calculating the local mean radiant temperature to experimental data and the classical method described by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (1997). The new method calculates the mean radiant temperature directly from the radiant intensity field at a particular point in the room. This approach, using the localized radiant intensity field, was theorized to be more accurate and flexible than using radiosities or surface temperatures and view factors currently described in the ASHRAE Handbook (1997). To benchmark the accuracy of the new method for calculating the mean radiant temperature, both methods of calculating the mean radiant temperature were compared to experimental measurements taken under carefully monitored conditions. The purpose of this process was to compare the classical and radiant intensity methods of mean radiant temperature calculation. From the four comparisons presented in this paper, using the radiant intensity field directly for the mean radiant temperature portion of the operative temperature calculations gave results 1--2 C (2--3 F) different from the classical method using view factors and surface temperatures and the experimental measurements. The radiant intensity method is a refinement to the mean radiant temperature calculation, enabling a direct solution of the radiant transfer equation that can handle extreme boundary conditions.

Palmer, J.M.; Chapman, K.S.

2000-07-01

72

Optics and materials research for controlled radiant energy transfer in buildings. Final technical report  

Energy Technology Data Exchange (ETDEWEB)

The primary objective of this project was to perform the optics and materials research necessary to identify and solve the technical problems associated with fabricating durable, variable reflectivity electrochromic windows for energy efficient buildings and vehicles. The research performed at the Tufts Electro-Optics Technology Center (EOTC) has identified and solved nearly all the significant problems, as discussed below in this final technical report. There still remains, however, one important problem to be solved--i.e., to better understand the science of deposition processes and thereby develop and optimize one or more production-worthy deposition processes that could be used for the practical production of affordable, variable reflectivity electrochromic windows. Therefore, it is recommended that such studies be carried out with the goals of: (1) determining the probable practical limits of performance; and, very importantly, (2) to develop and optimize deposition processes that could be used for the practical production of affordable electrochromic windows.

Goldner, R.B.

1996-07-01

73

Concentrating collectors  

Energy Technology Data Exchange (ETDEWEB)

Selected specifications from sixteen concentrating collector manufacturers are tabulated. Eleven are linear parabolic trough collectors, and the others include slats, cylindrical trough, linear Fresnel lens, parabolic cylindrical Fresnel lens, and two point focus parabolic dish collectors. Also included is a brief discussion of the operating temperatures and other design considerations for concentrating collectors. (LEW)

1981-06-01

74

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

Science.gov (United States)

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.

Chabane, Foued; Moummi, Noureddine

2014-04-01

75

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

International Nuclear Information System (INIS)

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

2009-03-01

76

Performance assessment of the Clouds and the Earth's Radiant Energy System (CERES) instruments aboard Terra and Aqua spacecraft  

Science.gov (United States)

Clouds and the Earth's Radiant Energy System (CERES) instruments were designed to measure the reflected shortwave and emitted longwave radiances of the Earth's radiation budget and to investigate the cloud interactions with global radiances for the long-term monitoring of Earth's climate. The three scanning thermistor bolometer sensors on CERES measure broadband radiances in the shortwave (0.3 to 5.0 micrometer), total (0.3 to <100 micrometer) and in 8 - 12 micrometer water vapor window regions. Of the five CERES instruments that are currently in operation, four of the CERES instruments (Flight Models1 through 4) fly aboard Earth Observing System (EOS) Terra and Aqua platforms with two instruments aboard each spacecraft, in 705 KM sun-synchronous orbits of 10:30 AM and 1:30 PM equatorial crossing time. A rigorous and comprehensive radiometric calibration and validation protocol comprising of various studies was developed to evaluate the calibration accuracy of the CERES instruments. The in-flight calibration of CERES sensors are carried out using the internal calibration module (ICM) comprising of blackbody sources and quartzhalogen tungsten lamp, and a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibration results are instrumental in determining the changes in CERES sensors' gains after launch from the prelaunch determined values and the on-orbit gain variations. In addition to the broadband response changes derived from the on-board blackbody and the tungsten lamp, the shortwave and the total sensors show a spectrally dependent drop in responsivity in the shorter wavelegth region below one micron that were brought to light through validation studies. The spectrally dependent changes were attributed to the instrument operational modes and the corrections were derived using the sensor radiance comparisons. This paper covers the on-orbit behavior of CERES sensors aboard the Terra and Aqua spacecraft and the determination of the sensor response changes utilising the in-flight calibration and the radiance measurement comparisons viewing various targets. The corrections for the sensor response changes were incorporated in the radiance calculations of CERES Edition3 data products.

Thomas, Susan; Priestley, K. J.; Shankar, M.; Smith, N. M.; Loeb, N. G.; Walikainen, D. R.; Hess, P. C.; Wilson, R. S.; Smith, N. P.

2013-09-01

77

Research on Flat Solar Collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Thesis analyzes one of the spheres of alternative energy supply – the solar energy. The main objective of the Thesis is to determine the energy rates of the solar collector and its accumulative capacity. The Paper introduces a stand on the solar collector research which consists of a flat solar collector, heat accumulator and auxiliary equipment. The research object of the Thesis is a laboratory flat solar collector and its system. The Thesis analyses the constructions of the solar coll...

2005-01-01

78

Methods for measurement of electron emission yield under low energy electron-irradiation by collector method and Kelvin probe method  

International Nuclear Information System (INIS)

Secondary electron emission yield of gold under electron impact at normal incidence below 50 eV was investigated by the classical collector method and by the Kelvin probe method. The authors show that biasing a collector to ensure secondary electron collection while keeping the target grounded can lead to primary electron beam perturbations. Thus reliable secondary electron emission yield at low primary electron energy cannot be obtained with a biased collector. The authors present two collector-free methods based on current measurement and on electron pulse surface potential buildup (Kelvin probe method). These methods are consistent, but at very low energy, measurements become sensitive to the earth magnetic field (below 10 eV). For gold, the authors can extrapolate total emission yield at 0 eV to 0.5, while a total electron emission yield of 1 is obtained at 40±1 eV.

2010-09-01

79

Plant Production in Solar Collector Greenhouses - Influence on Yield, Energy Use Efficiency and Reduction in CO2 Emissions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A semi-closed solar collector greenhouse was tested to evaluate the yield and the energy saving potential compared with a commercial greenhouse. As such, new algorithm for ventilation, carbon dioxide (CO2) enrichment, as well as for cooling and heating purposes initiated by a heat pump, cooling fins under the roof and a low temperature storage tank were developed. This cooling system showed that the collector greenhouse can be kept longer in the closed operation mode than a commerc...

2013-01-01

80

Liquid temperature determination in a seasonal heat storage at joint operation with a solar collector and thermal energy consumer  

Energy Technology Data Exchange (ETDEWEB)

Usual solar thermal systems include a solar collector providing solar power conversion into the thermal form and a heat storage accumulating thermal energy, the great capacity of storage systems allows heating and hot water supply during the cold season. The joint operation of the solar collector and a seasonal heat storage has a cyclic mode day by day. The following operation scheme is analyzed in the paper: in night liquid (water) does not circulate; after sunrise the solar collector is warmed up and after its temperature reaching the temperature of water in the thermal energy storage TTS circulation is switched on and thermal power is transferred to the heat storage; after midday water temperature in the solar collector decreases and circulation stops when it becomes equal to the heat storage temperature. TTS increase results in the reduction of the duration of the joint operation of the solar collector and the energy storage and in the decrease of the heat power input. A functional connection between the daily input of power from the solar collector and an average temperature in the heat storage is of importance for technological calculations. The moments of the beginning and end of circulation and daily heat input from the solar collector are determined under the assumption of the sinusoidal law of solar radiation coming in the day-time. Then the heat balance equation is solved for the whole power system with taking into account power consumption and heat losses. The polynomial approximation for the dependence of heat input upon heat carrier temperature permits obtaining an analytical solution for the seasonal behavior of the liquid temperature in the thermal energy storage. The obtained dependence of TTS upon time allows calculation of this parameter with admissible accuracy at the stage of the project development proceeding from the performance of the solar collector and heat storage and from the averaged meteorological data.

Sivoraksha, V.E.; Zolotko, K.E.; Markov, V.L.; Petrov, B.E.; Lyagushyn, S.F.

1998-07-01

 
 
 
 
81

Black Liquid Solar Collector Demonstrator.  

Science.gov (United States)

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)

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

1979-01-01

82

Karlsruhe electron collector testbench  

Energy Technology Data Exchange (ETDEWEB)

A new collector design for electron coolers was done in the Karlsruhe electron cooling group at LEAR (CERN). The performance of the collector was tested in a linear set-up with an electron beam of energies lower than 18 keV and a current of up to 1.25 A. In this range, current loss rates below 6 x 10/sup -5/ were achieved at a collector perveance of less than or equal to27..mu..AV/sup -3/2/. The maximum collector perveance in the present set-up is 37 ..mu..AV/sup -3/2/.

Poth, H.; Seligmann, B.; Woertge, M.; Wolf, A.

1988-01-01

83

Novel concept for producing energy integrating a solar collector with a man made mountain hollow  

Energy Technology Data Exchange (ETDEWEB)

The concept of the solar chimney thermal power technology was proven with the successful operation of the Manzanares prototype built in the 1980s. However, all previous attempts at producing energy from a commercial solar chimney thermal power plant on a large scale have failed because of bad engineering and safety. A novel concept for producing energy by integrating a solar collector with a mountain hollow is presented and described. Solar energy is collected in the collector and heats the ground, which is used to store heat energy and heat the indoor air. Then, the hot air is forced by the pressure difference between it and the ambient air to move along the tilted segment and up the vertical segment of the 'chimney', driving the turbine generators to generate electricity. The mountain hollow, formed by excavation in a large-elevation mountain, can avoid the safety issues of erecting a gigantic concrete chimney, which is needed for commercial solar chimney thermal power plants. Furthermore, it can also save a great amount of construction materials for constructing a robust chimney structure and reduce the energy cost to a level less than that of a clean coal power plant, providing a good solution to the reclamation and utilization of undeveloped mountains, especially in mountainous countries. (author)

Zhou, Xinping [School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074 (China); Yang, Jiakuan; Wang, Jinbo; Xiao, Bo [School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road Wuhan, Hubei 430074 (China)

2009-03-15

84

Geothermal energy - Handbook of cage-type collectors; Projekt Handbuch Erdwaermekoerbe. Dokumentation, Auslegung und Anwendungsbeispiele  

Energy Technology Data Exchange (ETDEWEB)

This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the use of cage-type ground-loop collectors used as the heat or cold source for heat-pump installations. The report describes the operating principle, functioning and application of such installations. Also, examples of installations are given and typical installations are documented. Simple rules for the dimensioning of the installations are presented. The suitability of such systems as an alternative to traditional ground loops and borehole heat exchangers for use in the heating systems of smaller single-family homes is discussed.

Bassetti, S.; Rohner, E.

2005-07-01

85

High efficiency radiant burners greatly enhance heat transfer  

Energy Technology Data Exchange (ETDEWEB)

Transfer of heat by thermal radiation usually is more efficient than convective heat transfer. This can result in higher productivity and/or lower operating costs. Apart from this, radiative heat transfer needs no direct contact between product and hot combustion gases. For this reason radiation can also improve product quality. For several years ECN has been developing ceramic foam burners by order of the Netherlands Agency for Energy and the Environment (NOVEM). Apart from the standard surface burner ECN develops new types of radiant burners. Whereas a normal surface burner radiates 25% of the energy input in the best case, the other burners can reach up to 70%. However, not only the radiant intensity incident on a product is important. Only if the radiation is actually absorbed in the product heat transfer is realised. This can be improved by matching the emission spectrum of the burner with the absorption spectrum of the product. A spectro-radiometer is used to develop and optimise coatings for radiant burners. Some experimental results of the multi-layer burner (100-250 kW/m{sup 2} radiant output, about 50% efficiency) and multi-stage radiant burner (50- 100 kW/m{sup 2} radiant output, about 70% efficiency) will be discussed. These include radiant output for several cases. Some numerical results will be presented to help understanding the different processes going on with a radiant burner. 8 figs., 5 refs.

Tjeng, S.L.; Van der Drift, A.; Beckers, G.J.J.; Rabou, L.P.L.M.

1995-08-01

86

Plant Production in Solar Collector Greenhouses - Influence on Yield, Energy Use Efficiency and Reduction in CO2 Emissions  

Directory of Open Access Journals (Sweden)

Full Text Available A semi-closed solar collector greenhouse was tested to evaluate the yield and the energy saving potential compared with a commercial greenhouse. As such, new algorithm for ventilation, carbon dioxide (CO2 enrichment, as well as for cooling and heating purposes initiated by a heat pump, cooling fins under the roof and a low temperature storage tank were developed. This cooling system showed that the collector greenhouse can be kept longer in the closed operation mode than a commercial one resulting in high levels of CO2 concentrations, relative humidity and temperatures. Based on these conditions, the photosynthesis and associated CO2 fixations within the plant population were promoted during the experiment, resulting in a yield increase by 32%. These results were realized, although the mean light interception by energy screens and finned tube heat exchangers was increased by 11% compared to the reference greenhouse. The energy use efficiency was improved by 103% when the collector greenhouse was considered as energy production facility. In this context, the energy saving per kilogram produced tomatoes in the collector greenhouse is equivalent to the combustion of high amounts of different fossil fuels, where the reduced CO2 emissions ranged between 2.32 kg and 4.18 kg CO2 per kg produced tomatoes. The generated total heat was composed of approximately one-third of the latent heat and over two-thirds of the sensible heat, where a maximum collector efficiency factor of 0.7 was achieved.

Dennis Dannehl

2013-09-01

87

Solar collector manufacturing activity, 1990  

International Nuclear Information System (INIS)

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

88

Solar collector  

Energy Technology Data Exchange (ETDEWEB)

A solar collector is provided having an inner core for absorbing solar radiation enclosed within a polygonal shaped glass housing. The inner core includes a series of outwardly extending projections which extend towards the inner surface of the glass housing and a fluid passageway is defined within the inner core. The core and its projections are either made from or coated with a material capable of absorbing solar radiation and emitting infrared radiation. The glass housing, which is substantially opaque to infrared radiation, maintains such infrared radiation emitted by the core within the triangular housing, and thus proximate to the central core. In this manner, a substantial portion of the heat energy of the emitted infrared radiation is transferred to fluid flowing through the fluid passageway within the core, and is not lost by convection. Flat mirrors can be used to direct solar energy to the glass housing and core.

Begun, J.A.

1982-07-20

89

Modernization of an industrial-building heating installation with energy-saving gas-fired dark radiant heaters; Modernisierung einer Hallenheizung mit energiesparenden, gasbefeuerten Dunkelstrahlern  

Energy Technology Data Exchange (ETDEWEB)

The buildings of long-established Siegerland company Achenbach, located at Kreuztal-Buschhuetten, were equipped with modern, gas-fired dark radiant heaters in the course of a number of work phases between 2002 and 2004. The decision in favour of a heating system based on dark emitters was taken, in particular, in the context of the second and third modernization phases, in cooperation with the Hellmich and Partner GmbH engineering consultancy, of Siegen, following thorough energy-engineering studies. Hellmich and Partner expressed the opinion that the planning of building systems in such a way that a balanced ratio between investment and operating costs is achieved is, ultimately, quite simply more cost-effective for the client. Investment costs must not be viewed in isolation. (orig.)

Schulte, J. [Schulte Hallenheizungen, Arnsberg (Germany)

2005-03-01

90

Parabolic trough solar collector plant on polar mounting for industrial thermal energy production (Modena - Italy)  

Energy Technology Data Exchange (ETDEWEB)

This final report covering the description of the installation and experience gained during experimental operation has been drawn up based upon the work program agreed upon between the EUROPEAN ECONOMIC COMMUNITY and ANSALDO IMPIANTI S.p.A. within the scope of the contract SE/222/81 for the demonstrative implementation of a parabolic trough solar collector plant on polar mounting for industrial thermal energy production. In addition to the technical description of the project, this report also includes an aggregate evaluation of the costs incurred for this project and the cost of the produced thermal energy. An analysis of the technical problems encountered during the execution of this first plant and the economic evaluations reported in this paper will provide sufficient indications regarding the prospects for large scale installation of similar plants and the difficulties with which the users, manufacturers of components and installers will have to cope.

Bisagni, M.

1984-01-01

91

Experimental and theoretical study of a hydronic radiant-ceiling-panel heating system  

Energy Technology Data Exchange (ETDEWEB)

The objective of this study is to improve the design of hydronic radiant panel systems through the understanding of the thermal performance of panel systems. The scope includes performing experiments using testing facilities and the radiant panel ceiling in the Energy Research House, and developing a theoretical model that can predict heat transfer from a radiant ceiling panel. In the experimental part, a solar-radiant heating system was field tested to examine the feasibility of using a radiant system coupled to a solar heating system to provide space heating. The test results verified the concept that a radiant panel ceiling, due to its extended heat transfer surface, can effectively utilize low temperature heat sources such as solar energy. A study on the transient thermal response of the radiant ceiling and room enclosure was also performed. Another experimental study performed at the Energy Research House was a comparison of radiant heating and forced-air heating. It was concluded that the radiant heating was 15 to 20% more energy efficient than forced-air heating in normal winter conditions. Theoretical modeling of the radiant panel heating system was performed, the model predicted the thermal behavior of the radiant panel to a reasonable accuracy.

Zhang, Z.

1987-01-01

92

The determination of space parameters of the heliostatic collector field  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2006-01-01

93

Design and performance of line-axis concentrating solar-energy collectors  

Energy Technology Data Exchange (ETDEWEB)

A model for the thermal analysis of compound parabolic concentrating (CPC) collectors has been developed, which provides more accurate performance predictions than those proposed previously. This model was employed to compare the performance of various CFC configurations. The optics of parabolic-trough concentrating (PTC) collectors with small concentration ratios were analysed in detail. The fraction of the diffuse insolation that can be exploited by PTC collectors was found to be significant for concentration ratios less than ten. The effects of the angular distribution of the diffuse insolation and the total optical error of the concentrating system on the performance of a PTC collector have been quantified.

Prapas, D.E.

1987-06-01

94

Solar energy transfer member for introduction into an envelope of a solar collector  

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a member for transferring solar energy by a heat transfer fluid. It comprises an assembly of three tubes, the first being introduced into the hollow part of cross-section (Sv) of a collector envelope, the second providing the upstream connection of the general circuit to the said member, comprising a straight portion which penetrates the first tube and a flattened portion which is to be engaged with the flattened portion of a third tube which, downstream, connects said member to the general fluid circulation circuit. The first tube is sealed by means of a hollow connecting plug and the cross-sections (S1) and (S2), respectively of the first and second tubes are selected in such a way that (S1-S2) is substantially equal to (S2), the crosssection (S1) being itself close to the cross-section (Sv) of the hollow part of the envelope.

Herbert, P.; Scoarnec, L.

1982-10-12

95

Chaotic dynamics of a classical radiant cavity  

CERN Multimedia

The statistical properties of a classical electromagnetic field in interaction with matter are numerically investigated on a one-dimensional model of a radiant cavity, conservative and with finite total energy. Our results suggest a trend towards equipartition of energy, with the relaxation times of the normal modes of the cavity increasing with the mode frequency according to a law, the form of which depends on the shape of the charge distribution.

Benenti, G; Guarneri, I; Benenti, Giuliano; Casati, Giulio; Guarneri, Italo

1999-01-01

96

Heating industrial premises with low-temperature radiant tubes  

Energy Technology Data Exchange (ETDEWEB)

Natural-gas-fired radiant-tube heating systems are often a food choice for industrial workshops because they efficiently emit an amount of heat and light comparable to the sun's. A typical system comprises a gas burner and combustion chamber, radiant tubes made of steel, a reflecting plate, a ventilator, a double solenoid valve, a pressure regulator, and automatic controls. A gas-fired radiant-tube heating system installed at a French clothing factory in 1977 cut energy consumption by 39%, mainly because the tubes concentrated the warmth where it was needed for the workers rather than heated the entire volume of air in the building.

Prezat, J.; Robert, G.

1980-12-01

97

Sandia invention to make parabolic trough solar collector systems more energy efficient  

Science.gov (United States)

This news release, from Sandia National Laboratories, announces the development of a system to align the long parabolic trough mirrors in a solar collector, thereby making it much more efficient. The article contains a description of how such trough solar collector systems and the new mirror alignment devices operate. Images are provided along with an outline of the group's anticipated progress.

2007-09-25

98

Building Space Heating with a Solar-Assisted Heat Pump Using Roof-Integrated Solar Collectors  

Directory of Open Access Journals (Sweden)

Full Text Available A solar assisted heat pump (SAHP system was designed by using a roof-integrated solar collector as the evaporator, and then it was demonstrated to provide space heating for a villa in Tianjin, China. A building energy simulation tool was used to predict the space heating load and a three dimensional theoretical model was established to analyze the heat collection performance of the solar roof collector. A floor radiant heating unit was used to decrease the energy demand. The measurement results during the winter test period show that the system can provide a comfortable living space in winter, when the room temperature averaged 18.9 °C. The average COP of the heat pump system is 2.97 and with a maximum around 4.16.

Zhiyong Yang

2011-03-01

99

Think GREEN - Utilizing Renewable Solar Energy  

Science.gov (United States)

Solar energy is radiant energy that is produced by the Sun. Every day the Sun radiates an enormous amount of energy. How much solar energy a place on Earth receives depends on several conditions. In this lesson, students will explore real NASA satellite data for energy from the Sun and cloud cover for their area to determine if they can harness this solar energy, a renewable energy source, by using a solar collector. They will develop skills in graphing and reading graphs.

100

Satellite Collectors of Solar Energy for Earth and Colonized Planet Habitats  

Science.gov (United States)

Summary An array of 55,000 40-foot antennas can generate from the rays of the Sun enough electrical power to replace 50 The economic potential is huge. There are new industries that will only grow and there are different ways to collect solar energy, including wind power. The energy sources we rely on for the most part are finite - fossil fuels, coal, oil and natural gas are all limited in supply. The cost will only continue to rise as demand increases. The time of global economic crossover between the EU, Asia Pacific and North America is coming within less than five years. The biggest opportunity for solar energy entrepreneurs would seem to be in municipal contracting where 1500 40-foot stacking antennas can be hooked into a grid to power an entire city. The antenna can generate 45 kilowatts of energy, enough to satisfy the electrical needs 7x24 of ten to twenty homes. It is possible to design and build 35-by-80-foot pedestals that track the sun from morning until night to provide full efficiency. A normal solar cell looks in the sky for only four or five hours of direct sunlight. Fabrication of these pedestals would sell for USD 50, 000-70,000 each. The solar heat collected by the antennas can be bounced into a Stirling engine, creating electricity at a focal point. Water can be heated by running through that focal point. In addition, salt water passing through the focal point can be desalinated, and since the antenna can generate up to 2,000 degrees of heat at the focal point. The salt water passing through the focal point turns to steam, which separates the salt and allows the steam to be turned into fresh drinking water. Collector energy can be retained in betavoltaics which uses semiconductors to capture energy from radioactive materials and turn it into usable electricity for automobiles. In a new battery, the silicon wafers in the battery are etched with a network of deep pores. These pores vastly increase the exposure surface area of the silicon, allowing it to absorb more energy and making the antenna collector 20 times more efficient than planar designs. A tracking pedestal powered by betavoltaics can follow the sun. With a 500-sun photovoltaic cell underneath a Fresnal lens magnifies and distributes the sun's energy at 500 times. Primary results and the main conclusions This idea is revolutionary and utilizes satellite tracking abilities to follow the sun, maintaining a constant energy source that can reach 700 to 800 degrees. This technology will have many applications, from instant fresh water in the form of steam to the use of fiber optics to filter natural light through a building. With the direction of the oil and energy costs continuing to spiral upward, there has been recent emphasis on alternative energy that is transmitted from space. Satellite antenna manufacturers can move quickly to production and create a revolution in sustainable energy that was never thought of before. The efforts of the United States, Russia, China, and India to colonize the Moon and Mars would be greatly enhanced by use of satellite solar collectors and betavoltaics electrical energy technologies for the colonies' habitats. Introduction This study was undertaken for the Global environment is in a crisis. The rich oil producing countries of Russia, Saudi Arabia, Venezuela, and Africa, have been at war to gain monopoly power and to restrict the space based explorations of the solar system. The physics of solar energy transmission to electrical mechanical energy is unique in improving the economies of the entire community of Nations. It is easy to produce satellite antennas, thus, satellite antennas can now be used as solar panels which can generate free power from the sun by converting sunlight to electricity. Solar Panels require no moving parts; have zero emissions, and no maintenance. These antennas will revolutionize the use of solar rays from the sun to benefit a global grid. These "collectors of free energy" are able to harness solar energy for thermal heating, desalination, lighting, and electricity. Further,

Kusiolek, Richard

 
 
 
 
101

The parabolic concentrating collector: A tutorial  

Science.gov (United States)

A tutorial overview of point-focusing parabolic collectors is presented. Optical and thermal characteristics are discussed. Data representing typical achievable collector efficiencies are presented and the importance of balancing collector cost with concentrator quality is argued through the development of a figure of merit. Various types of two-axis tracking collectors are described. The Department of Energy program to develop these devices is briefly discussed, as are present and projected costs for these collectors.

Truscello, V. C.

1979-01-01

102

Measured radiant thermal fields in industrial spaces served by high intensity infrared heater  

Energy Technology Data Exchange (ETDEWEB)

Work stations in industrial spaces are frequently arranged at a significant distance from each other. Local heating applying, among others, the gas-fired direct radiant heaters, is a viable alternative to the central heating. Radiant heaters provide heat comfort to workers and guarantee the maintenance of higher temperatures of the surrounding walls at a lower indoor temperature. The advantage of heating by gas-fired radiant heaters is the lower operational cost comparing to another systems. It uses less energy to obtain 2-3 K lower indoor temperature than in case of heating by conventional systems. The radiant temperature at work stations should be high enough to eliminate thermal discomfort, which in particular, is a result of radiant temperature asymmetry that may be caused by excessive and asymmetric overheating of the human body by a radiant heater. This paper includes formulas, based on the results of the self-designed test, which are then used in the calculation of the radiant temperature and the radiant temperature asymmetry, depending on the radiant heater position and the indoor temperature. This paper presents also the most recognized interrelations between the radiant temperature and its asymmetry. The discussed parameters are particularly significant in the heating process using high-temperature radiant heaters. (author)

Dudkiewicz, Edyta; Jezowiecki, Janusz [Wroclaw University of Science, Faculty of Environmental Engineering, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

2009-01-15

103

Dust collector  

International Nuclear Information System (INIS)

The present invention is directed to a dust collector. Dust collector (100) has a housing (102) separated by partition into inlet chamber and clean air chamber. A clean air drum rotatably supports columns of horizontally extending, filter elements. A low pressure, high volume pulse apparatus is operable through blowpipe to sequentially provide a low pressure reverse pulse to a column of filter elements thereby separating any dust cake from them and allowing it to fall into conical portion for removal from collector by air lock. The motor which rotates blowpipe also disengageably rotates clean air drum and attached filter elements to align a column of filter elements with door assembly for maintenance

1985-01-01

104

Radiant panel perimeter heating options: Effectiveness and thermal comfort  

Energy Technology Data Exchange (ETDEWEB)

Analysis of perimeter heating in a room by a radiant ceiling panel supplementing a central air-heating system is performed numerically. Located above the window in a suspended ceiling, the heated panel thermally affects both the room and the plenum above the panel. In multistory office buildings the thermal comfort of a room is influenced not only by the outdoor temperature and the radiant panel within the room but also by the enclosures above and beneath the room. Thermal comfort and energy efficiency in the room were investigated as functions of various parameters, including (1) effect of insulation, or lack of it, on top (plenum side) of the radiant panel; (2) effect of adding a partition in the plenum to determine if the heat lost form the top of the panel can be directed to the floor located directly above the panel; and (3) radiant panel surface temperature.

Freestone, M.D.; Worek, W.M. [Univ. of Illinois, Chicago, IL (United States). Dept. of Mechanical Engineering

1996-11-01

105

Distributed collectors for the conversion of solar thermal energy into electric power; Sistemas distribuidos de conversao heliotermoeletrica  

Energy Technology Data Exchange (ETDEWEB)

In this chapter some important topics related to distributed concentrating collectors are discussed such as: general properties of concentrating collectors; parabolic collectors; common bias and errors; and parabolic disks among others. 9 refs., 12 figs., 2 tabs.

Fraidenraich, Naum [Pernambuco Univ., Recife, PE (Brazil). Centro de Energia Nuclear; Lyra, Francisco [Companhia Hidroeletrica do Sao Francisco (CHESF), Recife, PE (Brazil)

1995-12-31

106

3X compound parabolic concentrating (CPC) solar energy collector. Final technical report  

Energy Technology Data Exchange (ETDEWEB)

Chamberlain engineers designed a 3X compound parabolic concentrating (CPC) collector for the subject contract. The collector is a completely housed, 105.75 x 44.75 x 10.23-inch, 240-pound unit with six each evacuated receiver assemblies, a center manifold and a one-piece glass cover. A truncated version of a CPC trough reflector system and the General Electric Company tubular evacuated receiver have been integrated with a mass producible collector design suitable for operation at 250 to 450/sup 0/F. The key criterion for optimization of the design was minimization of the cost per Btu collected annually at an operating temperature of 400/sup 0/F. The reflector is a 4.1X design truncated to a total height of 8.0 inches with a resulting actual concentration ratio of 2.6 to 1. The manifold is an insulated area housing the fluid lines which connect the six receivers in series with inlet and outlet tubes extending from one side of the collector at the center. The reflectors are polished, anodized aluminum which are shaped by the roll form process. The housing is painted, galvanized steel, and the cover glass is 3/16-inch thick tempered, low iron glass. The collector requires four slope adjustments per year for optimum effectiveness. Chamberlain produced ten 3X CPC collectors for the subject contract. Two collectors were used to evaluate assembly procedures, six were sent to the project officer in Albuquerque, New Mexico, one was sent to Argonne National Laboratory for performance testing and one remained with the Company. A manufacturing cost study was conducted to estimate limited mass production costs, explore cost reduction ideas and define tooling requirements. The final effort discussed shows the preliminary design for application of a 3X CPC solar collector system for use in the Iowa State Capitol complex.

Ballheim, R.W.

1980-04-25

107

Solar collector  

Energy Technology Data Exchange (ETDEWEB)

Solar collector of the heat pipe type is described, comprising in per se known manner a case or container containing a heat pipe absorber of the solar energy, insulation placed between the absorber and the bottom of the container, at least one glass partition on the container, as well as the devices necessary for assembling and sealing the system. Said heat pipe absorber is constituted by a tightly sealed case formed by a first heat collecting wall, a second wall forming the base and sidewalls, a capillary system lining the inside of the case and a heat transfer fluid which wets this capillary system. The capillary system comprises a first part applied to the first wall and a second part applied to the second wall, and at least one of the said first and second walls is deformable under the action of an overpressure in the case. Said first and second parts of the capillary system have no point of contact when the wall is deformed and at least one line of contact when the wall is not deformed.

Devin, B.; Durand, J.; Guillemot, M.

1982-02-16

108

Simulated comparison of the useful energy gain in fixed and tracking flat plate and evacuated tube collectors  

Energy Technology Data Exchange (ETDEWEB)

A study is presented to compare the useful energy gain in fixed, full-tracking and single-tracking (azimuthal angle) flat plate, and evacuated tube collectors. The study includes the consideration of using a single or double cover as well as an ''ordinary'' or a selective plate surface. A computer simulation was performed using actual hourly solar and weather data for the entire year of 1977, at Kings Point, N.Y. 7 refs.

Drago, P.

1981-01-01

109

Highlights of the solar total energy systems, distributed collector systems, and research and development projects. Semiannual review, 26-27 January 1976, Atlanta, Georgia  

Energy Technology Data Exchange (ETDEWEB)

The highlights of the ERDA Solar Thermal Branch Semiannual Review held in Atlanta, Georgia, on January 26-27, 1976, are presented. Status and plans for Total Energy Systems, Distributed Collectors, and Research and Development Projects are reviewed. (WHK)

Latta, A.F.

1976-03-26

110

Thermal model of attic systems with radiant barriers  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the first phase of a project to model the thermal performance of radiant barriers. The objective of this phase of the project was to develop a refined model for the thermal performance of residential house attics, with and without radiant barriers, and to verify the model by comparing its predictions against selected existing experimental thermal performance data. Models for the thermal performance of attics with and without radiant barriers have been developed and implemented on an IBM PC/AT computer. The validity of the models has been tested by comparing their predictions with ceiling heat fluxes measured in a number of laboratory and field experiments on attics with and without radiant barriers. Cumulative heat flows predicted by the models were usually within about 5 to 10 percent of measured values. In future phases of the project, the models for attic/radiant barrier performance will be coupled with a whole-house model and further comparisons with experimental data will be made. Following this, the models will be utilized to provide an initial assessment of the energy savings potential of radiant barriers in various configurations and under various climatic conditions. 38 refs., 14 figs., 22 tabs.

Wilkes, K.E.

1991-07-01

111

Leaves: Nature's Solar Collectors  

Science.gov (United States)

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…

Isabelle, Aaron D.; de Groot, Cornelis

2009-01-01

112

The determination of space parameters of the heliostatic collector field  

International Nuclear Information System (INIS)

The assurance of perpetual perpendicular insolation of solar collector absorber surface may increase the insolation energy by ca 42-45 %. A consequence of the increase 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. (authors)

2006-01-01

113

The determination of space parameters of the heliostatic collector field  

Directory of Open Access Journals (Sweden)

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.

Dušan Kudelas

2006-04-01

114

Analyses of On-orbit Determinations of the Clouds and the Earth Radiant Energy System (CERES) Thermistor Bolometer Sensor Zero-radiance Effects  

Science.gov (United States)

The Clouds and Earth's Radiant Energy System (CERES) missions were designed to measure broadband earth-reflected shortwave solar (0.3 micrometers to less than 5.0 micrometers) and earth-emitted longwave (5.0 micrometers to greater than 100 micrometers) radiances as well as earth-emitted narrow-band radiances in the water vapor window region between 8 micrometers and 12 micrometers. However, the CERES scanning thermistor bolometer sensor zero-radiance offsets were found to vary as much as 1.0 Wm (exp -2) sr (exp -1) with the scan angle measurement geometry due to gravitational forces and systematic electronic noise. To minimize the gravitational effects, the Tropical Rainfall Measuring Mission (TRMM) Spacecraft CERES sensors' offsets were derived on-orbit as functions of scan elevation and azimuth angles from the January 7-8, 1998 radiometric observations of deep cold space, representative of a 3 K blackbody. In this paper, the TRMM/CERES six orbit data base of on-orbit derived offsets is presented and analyzed to define the sampling requirements for the CERES sensors located on the Earth Science Enterprise (ESE) Terra Spacecraft and on the Earth Observing System (EOS) Afternoon (PM-1) Spacecraft, scheduled for launches in 1999 and 2000, respectively. Analyses of the TRMM/CERES shortwave sensor earth radiance measurements indicate that offsets can be determined on-orbit at the plus or minus 0.02 Wm (exp -2) sr (exp -1) precision level. Offset measuring techniques and sampling requirements are discussed for the TRMM and ESE missions. Ground, pre-launch Terra CERES cross-track scan offsets are presented and described which were measured as a function of scan angle.

Lee, Robert B., III; Thomas, Susan; Priestley, Kory J.; Barkstrom, Bruce R.; Paden, Jack; Pandey, Dhirendra K.; Smith, G. Louis; Al-hajjah, Aiman; Wilson, Robert S.

1999-01-01

115

Status and Operations at the Clouds and the Earth's Radiant Energy System (CERES) Ocean Validation Experiment (COVE) - Also a Baseline Surface Radiation Network (BSRN) Station  

Science.gov (United States)

25 km off the coast of Virginia, a lighthouse structure has been used for scientific measurements for over a decade. The CERES Ocean Validation Experiment (COVE) at Chesapeake Light is involved in several projects and networks. This report focuses on measurements and analysis made over the last 5 years at COVE. Being part of the BSRN network, most of the instruments at COVE are radiometers that measure both downwelling and upwelling flux at visible and infrared wavelengths. Basic meteorological parameters are also monitored. A table will show all the instrumentation and measurements being collected at COVE for the BSRN network as well as other data collections for aerosol, black carbon, total column water vapor and more. The initial motivation for COVE was to serve as a surface validation site for satellites. We compare modeled and actual downwelling shortwave and longwave measurements into 3 different sky scenarios (clear, partly cloudy and cloudy) over a number of years. Results show the best agreement for the clear sky model in both shortwave and longwave, with downwelling longwave correlating and having less mean bias than downwelling shortwave. COVE provides a wide range of measurements over an ocean environment with other examinations including aerosol studies, black carbon analysis and determination of spectral albedos from Multi-Filter Rotating Shadowband Radiometers (MFRSRs). One example displays how we can use these studies and analysis to trace smoke over the COVE site and how it affects our measurements.Chesapeake Light. Home of the Clouds and the Earth's Radiant Energy System (CERES) Ocean Validation Experiment (COVE) ` Location of Chesapeake Light. Home of COVE. 25 kilometers East of Virginia. Coordinates: 36.90 North, 75.71 West

Fabbri, B. E.; Schuster, G. L.; Denn, F. M.; Rutan, D. A.; Madigan, J. J.; Arduini, R. F.

2012-12-01

116

Radiative effects of African dust and smoke observed from Clouds and the Earth's Radiant Energy System (CERES) and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) data  

Science.gov (United States)

Cloud and aerosol effects have a significant impact on the atmospheric radiation budget in the tropical Atlantic because of the spatial and temporal extent of desert dust and smoke from biomass burning in the atmosphere. The influences of African dust and smoke aerosols on cloud radiative properties over the tropical Atlantic Ocean were analyzed for the month of July for 3 years (2006-2008) using colocated data collected by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and Clouds and the Earth's Radiant Energy System (CERES) instruments on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and Aqua satellites. Aerosol layer height and type can be accurately determined using CALIOP data through directly measured parameters such as optical depth, volume depolarization ratio, attenuated backscatter, and color ratio. On average, clouds below 5 km had a daytime instantaneous shortwave (SW) radiative flux of 270.2 ± 16.9 W/m2 and thin cirrus clouds had a SW radiative flux of 208.0 ± 12.7 W/m2. When dust aerosols interacted with clouds below 5 km, as determined from CALIPSO, the SW radiative flux decreased to 205.4 ± 13.0 W/m2. Similarly, smoke aerosols decreased the SW radiative flux of low clouds to a value of 240.0 ± 16.6 W/m2. These decreases in SW radiative flux were likely attributed to the aerosol layer height and changes in cloud microphysics. CALIOP lidar observations, which more accurately identify aerosol layer height than passive instruments, appear essential for better understanding of cloud-aerosol interactions, a major uncertainty in predicting the climate system.

Yorks, John E.; McGill, Matt; Rodier, Sharon; Vaughan, Mark; Hu, Yongxiang; Hlavka, Dennis

2009-09-01

117

Solar collector  

Science.gov (United States)

The field of this invention is solar collectors, and more particularly, the invention pertains to a flat plate collector that employs high performance thin films. The solar collector of this invention overcomes several problems in this field, such as excessive hardware, cost and reliability, and other prior art drawbacks outlined in the specification. In the preferred form, the apparatus features a substantially rigid planar frame (14). A thin film window (42) is bonded to one planar side of the frame. An absorber (24) of laminate construction is comprised of two thin film layers (24a, 24b) that are sealed perimetrically. The layers (24a, 24b) define a fluid-tight planar envelope (24c) of large surface area to volume through which a heat transfer fluid flows. Absorber (24) is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

Wilhelm, William G. (Cutchogue, NY)

1982-01-01

118

On the qualities of the air as affected by radiant energies (photocatalytic ionization processes for remediation of indoor environments)  

Energy Technology Data Exchange (ETDEWEB)

This paper presented new technologies and their applications to the remediation of indoor air environment. While tight building envelopes reduce energy losses, the design of buildings must now include advanced technologies integrated into heating, ventilation and air conditioning systems (HVACs) to ensure indoor environmental quality (IEQ). Airborne pollutants in indoor environments such as volatile organic compounds (VOCs), particulate matter (PM{sub x}) and bioaerosols can affect the health of building occupants. Increased costs have prompted energy conservation and more stringent operational standards for buildings. Various air treatment technologies can be used to control trace contaminants. Conventional processes, such as sorption, filtration, and disinfection, are now used in combination with advanced treatment processes, such as photocatalytic oxidation to oxidize VOCs, bipolar air ionization to agglomerate PM{sub x}, ozone generation, electrostatic precipitation, gas-phase filtration, solid media filtration, and ultraviolet disinfection to inactivate bioaerosols. Low levels of these contaminants are controlled by modular hybrid devices that are integrated into engineered systems. The development of these technologies is supplemented with better diagnostic techniques applied to domestic, institutional, and commercial installations. Engineered solutions require knowledge of the specific contaminants to be controlled, an ability to determine their distributions in time and space, and an understanding of the degree of control achievable by a specific technology. It was concluded that rationales for mitigation of IEQ include homeland security and defense; building safety; and, energy efficiency. The Leadership in Energy and Environmental Design (LEED) standards have been developed for both existing and new buildings, and include evaluation of factors associated with energy conservation and IEQ. 81 refs., 1 tab., 3 figs.

Daniels, S.L. [Ingenuity IEQ Inc., Midland, MI (United States)

2007-05-15

119

Solar hot water collector  

Energy Technology Data Exchange (ETDEWEB)

A hot water collector to be erected on the sloped roof of an enclosure so that solar energy, I.E. the rays of the sun, will shine on the collector and heat water flowing therein. The collector features a plurality of parallel generally rectilinear channels arranged on the roof, extending transversely to the pitch of the roof and extending horizontally and transversely across the sloped roof. Water flows from one end of a channel to the other and then down to the next lower channel. The water is heated by the sun as it flows along successive channels, and heated water is removed from the lowest channel for space heating or other uses. A specific configuration of solar hot water collector consisting of an elongated metal strip and a plurality of metal mounting brackets is also disclosed, as well as a method of installing a solar hot water collector on the sloped roof of an enclosure using a plurality of elongated metal strips.

Munroe, R.G.

1981-11-17

120

Heat yield and characteristics of solar collectors  

International Nuclear Information System (INIS)

The test results of the summer 1980 test on solar collectors are summarised. Apart from the 16 collectors tested under contract, two were investigated as a reference serving flat collectors, e.g. for the area of International Energy Agency (IEA), two were evacuated cylindrical collectors. The report allows the comparison of heat power outputs of the different products on the basis of the measured optical and thermal data values. (A.N.K.)

1981-01-01

 
 
 
 
121

Alternative energy sources IV; Proceedings of the Fourth Miami International Conference, Miami Beach, FL, December 14-16, 1981. Volume 1 - Solar Collectors Storage  

Science.gov (United States)

Aspects of solar measurements, solar collectors, selective coatings, thermal storage, phase change storage, and heat exchangers are discussed. The analysis and testing of flat-plate solar collectors are addressed. The development and uses of plastic collectors, a solar water heating system, solar energy collecting oil barrels, a glass collector panel, and a two-phase thermosyphon system are considered. Studies of stratification in thermal storage, of packed bed and fluidized bed systems, and of thermal storage in solar towers, in wall passive systems, and in reversible chemical reactions are reported. Phase change storage by direct contact processes and in residential solar space heating and cooling is examined, as are new materials and surface characteristics for solar heat storage. The use of R-11 and Freon-113 in heat exchange is discussed. No individual items are abstracted in this volume

Veziroglu, T. N.

1982-10-01

122

A search for space energy alternatives  

Science.gov (United States)

This paper takes a look at a number of schemes for converting radiant energy in space to useful energy for man. These schemes are possible alternatives to the currently most studied solar power satellite concept. Possible primary collection and conversion devices discussed include the space particle flux devices, solar windmills, photovoltaic devices, photochemical cells, photoemissive converters, heat engines, dielectric energy conversion, electrostatic generators, plasma solar collectors, and thermionic schemes. Transmission devices reviewed include lasers and masers.

Gilbreath, W. P.; Billman, K. W.

1978-01-01

123

Issues in the design of infrared radiant heating systems. Final report  

Energy Technology Data Exchange (ETDEWEB)

In the 1970s and 1980s, the Army placed infrared heaters in many installation buildings as an energy-conserving measure. Radiant systems require less maintenance, have lower first costs, and are advertised as more energy conserving than conventional heating systems. Though radiant systems have generally met expectations, the relative benefits of radiant systems have never been formally studied. This study reviewed and tested industry claims for radiant heaters, and experimentally compared gas-fired low-intensity infrared radiant tube-type heaters to conventional heaters at Fort Riley, KS. Technical issues in infrared heating design and available design guidance were reviewed. This report includes a list of radiant heater manufacturers and presents the lessons learned from the experimental investigation. Experience and results from a field demonstration, informal survey, literature search, several site visits, and industry contacts indicate that low-intensity infrared radiant heating systems exhibit a potential for energy savings. However, proper implementation, control, and operation are essential to achieving these savings. There is also a need for a specific, nonproprietary guidance for designing radiant heating systems.... Infrared energy, Heating equipment and supplies.

Morton, J.D.; Lawrie, L.K.; Nemeth, R.J.; Reed, J.; Rives, B.L.

1992-11-01

124

Energy flow and thermal comfort in buildings : Comparison of radiant and air-based heating & cooling systems  

DEFF Research Database (Denmark)

Varme- og køleanlæg kan inddeles i to hovedkategorier: konvektive systemer (fx. aircondition, aktiv kølebaffel, fan-coils) og stråle køling/varme systemer. De to systemer har forskellige former for varmeoverførsel; den første er hovedsageligt baseret på konvektion, mens den anden er baseret på både stråling og konvektion. Strålevarmesystemer har den fordel at kunne gøre brug af lav kilder (dvs. opvarmning ved lave temperature og køling ved høje temperaturer) og dermed reducere bygningers primære energiforbrug. Der er imidlertid en mangel på viden om varmeoverførsel fra terminalen mod rummet og på de parametre, der påvirker anlæggenes ydelse. Derfor er der foretaget en sammenligning af komfortbetingelserne og energiforbruget for fire typer anlæg (aktiv kølebaflen, strålende gulv, væg og loft) for et typisk kontorlokale, både numerisk og eksperimentelt. Fra den stationære numerisk analyse og fuldskalaforsøgene er det observeret, at forskellen mellem de to typer anlæg primært skyldes ændringer ventilationstab. Ved lave ventilationstilskud (under 0,5 ACH), har stråle- og luftbaserede systemer samme energibehov. Ved højere ventilationstilskud er strålevarmesystemers energiforbrug lavere end de luftbaserede systemers på grund af den højere lufttemperatur. Ved 2 ACH kan en strålevægs energibesparelser vurderes til ca. 10 % sammenlignet med den aktive kølebaflen (med hensyn til leveret energi). Asymmetrien mellem luft og strålingstemperatur, lufttemperaturgradienten og den mulige kortslutning mellem indløb og udløb spiller en lige så vigtig rolle ved reduceringen af strålevæggens kølebehov sammenlignet med den aktive kølebaflen. Jo højere et luftskifte og jo højere, jo større er de opnåede besparelser med en strålekølesystem. Derfor har strålekølesystemet et stort potentiale for energibesparelser i bygninger med et højt ventilationskifte (fx butikker, togstation, industriel opbevaring ). Blandt strålesystemer er der kun observeret små forskelle i den påtænkte geometri. Kun hvis beboerne antages at sidde ned, kan den store vinkelforhold med gulvet føre til en reduktion af energibehovet for gulvkølesystemer. Disse konklusioner gælder for fler-etagers eller højisolerede bygninger (R > 5 m2.K/W). Når det drejer sig om en enetagers bygning med et lavt isoleringsniveau, er strålesystemers effektivitet lavere på grund af de større klimaskærmstab, og et luftbaseret system kan være mere energieffektivt end et stråleanlæg (med hensyn til leveret energi). Et tilsvarende globalt komfort niveau er blevet observeret for stråle- og luftbaserede systemer i både numeriske og eksperimentelle undersøgelser, men de forskellige anlæg opnåede ikke den samme ensartethed i rummet. Den aktive kølebaflen opnår teoretisk de mest ensartede komfortbetingelser (når der ses bort fra risikoen for træk) efterfulgt af kølelofter. De mindst ensartede betingelser blev opnået med det afkølede gulv, på grund af store forskelle mellem siddende og stående stilling. Lokale komfortbetingelser (strålingstemperaturasymetrien, lufttemperaturgradient, risiko for træk) er også blevet evalueret både teoretisk og numerisk, og der er ikke observeret ubehag ved normal kølekapacitet. Udover denne sammenlignende undersøgelse af forskellige anlæg, er sammenhængen mellem kølesystemer og interne konvektionsstrømme også blevet undersøgt eksperimentelt. Sammenligningen med eksisterende modeller påpegede specificiteten af eksisterende sammenhænge og begrænsningen i deres anvendelsesområder. På grund af forskelle i indblæsning stråle, har eksisterende korrelationer en tendens til at overvurdere konvektionsstrømningen, især ved loftet. To fremgangsmåder er således blevet testet for bedre at kunne forklare strømingsformer i definitionen af konvektion koefficienter.

Le Dreau, Jerome

2014-01-01

125

BigHorn Home Improvement Center Energy Performance: Preprint  

Energy Technology Data Exchange (ETDEWEB)

This is one of the nation's first commercial building projects to integrate extensive high-performance design into a retail space. The extensive use of natural light, combined with energy-efficient electrical lighting design, provides good illumination and excellent energy savings. The reduced lighting loads, management of solar gains, and cool climate allow natural ventilation to meet the cooling loads. A hydronic radiant floor system, gas-fired radiant heaters, and a transpired solar collector deliver heat. An 8.9-kW roof-integrated photovoltaic (PV) system offsets a portion of the electricity.

Deru, M.; Pless, S.; Torcellini, P.

2006-04-01

126

Line-focus concentrating solar collectors  

Energy Technology Data Exchange (ETDEWEB)

An overview of the line-focus concentrating solar collector technology and applications is presented. Included are a description of the collectors, some of the key features of the engineering approach, instantaneous and all-day performance and operating data, temperature capabilities and limitations for selected collectors, projected future capabilities for peak and annual performance. Projected system capital costs and annualized life cycle costs for thermal energy produced are discussed. Several existing application projects which employ line concentrating collectors are reviewed, and finally, plans for future DOE-funded line concentrating collector projects are described.

Leonard, J. A.; Dugan, V. L.

1980-01-01

127

Solar collector  

Energy Technology Data Exchange (ETDEWEB)

A solar collector is designed for converting solar radiation into heat and transferring the heat thus collected, by means of a chamber formed of a window exposed to the sun and allowing passage of solar radiation, and of a bottom or opposite end-face. This radiation is absorbed by adequate means fitted inside this chamber, and the heat it entails is carried off outside the latter. Both the window and the bottom which form the chamber, are made of glass elements hermetically sealed to one another along their periphery by low-melt glass welding.

Boy-Marcotte, J.; Chevalier, P.J.; Grossin, R.J.; Junot, H.D.

1981-10-13

128

Magnetic droplet radiator collectors  

International Nuclear Information System (INIS)

Radiating heat via a droplet sheet offers a light weight, easily deployable means of rejecting energy from a spacecraft. Uncertainties in the trajectory of the droplets and splashing in the droplet collector can lead to unacceptable coolant mass losses. A study conducted at Brookhaven National Laboratory has investigated using ferrofluids with magnetic collectors to reduce these potential losses. Streams of ferrofluid droplets have been produced through 100 and 150 ?m orifices. These droplets have been accelerated in excess of five ''g's'' using permanent magnets and have been observed to behave stably and remain intact. Preliminary testing with thirty-seven parallel streams indicates that, except for collector splashing, multiple streams behave, from a fluid's viewpoint, like single streams. Single drops impacting under conditions known to produce satellite drops following impact were observed for varying magnetic conditions. At roughly one kilogauss, all incoming material would be captured under weightless conditions. Rebounding material tends to flow along lines of magnetic flux. Trade studies indicate that a range of conditions exists over which magnetic collections offer a weight advantage over a heat pipe radiator or droplet radiator with a large collector. 11 figs

1985-01-01

129

A MCRT and FVM coupled simulation method for energy conversion process in parabolic trough solar collector  

Energy Technology Data Exchange (ETDEWEB)

A coupled simulation method based on Monte Carlo Ray Trace (MCRT) and Finite Volume Method (FVM) is established to solve the complex coupled heat transfer problem of radiation, heat conduction and convection in parabolic trough solar collector system. A coupled grid checking method is established to guarantee the consistency between the two methods and the validations to the coupled simulation model were performed. Firstly, the heat flux distribution on the collector tube surface was investigated to validate the MCRT method. The heat flux distribution curve could be divided into 4 parts: shadow effect area, heat flux increasing area, heat flux reducing area and direct radiation area. The heat flux distribution on the outer surface of absorber tube was heterogeneous in circle direction but uniform in axial direction. Then, the heat transfer and fluid flow performance in the LS-2 Solar Collector tube was investigated to validate the coupled simulation model. The outlet temperatures of the absorber tube predicted by the coupled simulation model were compared with the experimental data. The absolute errors are in the range of 1.5-3.7 C, and the average relative error is less than 2%, which demonstrates the reliability of the coupled method established in this paper. At last, the concentrating characteristics of the parabolic trough collectors (PTCs) were analyzed by the coupled method, the effects of different geometric concentration ratios (GCs) and different rim angles were examined. The results show the two variables affect the heat flux distribution. With GC increasing, the heat flux distributions become gentler, the angle span of reducing area become larger and the shadow effect of absorber tube become weaker. And with the rim angle rising, the maximum value of heat flux become lower, and the curve moves towards the direction {phi} = 90 . But the temperature rising only augments with GC increasing and the effect of rim angle on heat transfer process could be neglected, when it is larger than 15 . If the rim angle is small, such as {theta}{sub rim} = 15 , lots of rays are reflected by glass cover, and the temperature rising is much lower. (author)

He, Ya-Ling; Xiao, Jie; Cheng, Ze-Dong; Tao, Yu-Bing [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China)

2011-03-15

130

Controlled Production of Sub-Radiant States of a Diatomic Molecule in an Optical Lattice  

CERN Document Server

We report successful production of sub-radiant states of a two-atom system in a three-dimensional optical lattice starting from doubly occupied sites in a Mott insulator phase of a quantum gas of atomic ytterbium. We can selectively produce either sub-radiant 1g state or super-radiant 0u state by choosing the excitation laser frequency. The inherent weak excitation rate for the sub-radiant 1g state is overcome by the increased atomic density due to the tight-confinement in a three-dimensional optical lattice. Our experimental measurements of binding energies, linewidth, and Zeeman shift confirm observation of sub-radiant levels of the 1g state of the Yb_2 molecule.

Takasu, Yosuke; Takahashi, Yoshiro; Borkowski, Mateusz; Ciury?o, Roman; Julienne, Paul S

2012-01-01

131

Performance evaluation of a radiant floor cooling system integrated with dehumidified ventilation  

Energy Technology Data Exchange (ETDEWEB)

The radiant floor cooling system can be used as an alternative to all-air cooling systems, using the existing Ondol system (a radiant floor heating system) in Korea to save energy and maintain indoor thermal comfort. Unfortunately, a radiant floor cooling system may cause condensation on the floor surface under hot and humid conditions during the cooling season. In addition, the radiant floor system does not respond quickly to internal load changes due to the thermal storage effect of the concrete mass, which is usually present in radiant floor cooling systems. This study proposes a radiant floor cooling system integrated with dehumidified ventilation, which cools and dehumidifies the outdoor air entering through the cooling coil in the ventilator by lowering the dew-point temperature to prevent condensation on the floor surface. Furthermore, outdoor reset control was used to modulate the temperature of chilled water supplied to the radiant floor, and indoor temperature feedback control was then used to respond to the internal load changes. To evaluate the performance of the radiant floor cooling system integrated with dehumidified ventilation, both a physical experiment in a laboratory setting and TRNSYS simulation for an apartment in Korea have been conducted. As a result, it was found that the proposed system was not only able to solve the problem of condensation on a floor surface but also to control the indoor thermal environment within the acceptable range of comfort. Furthermore, the proposed system improved the responsiveness to internal load changes. (author)

Song, Doosam [Department of Architectural Engineering, Sungkyunkwan University, Seoul (Korea); Kim, Taeyeon [Department of Architectural Engineering, Yonsei University, Seoul (Korea); Song, Suwon; Hwang, Suckho [Center for Sustainable Buildings, Yonsei University, Seoul (Korea); Leigh, Seung-Bok [Department of Architecture, Yonsei University, Seoul (Korea)

2008-08-15

132

Exergy analysis of photovoltaic solar collector  

International Nuclear Information System (INIS)

The exergy analysis (availability or second law analysis) is applied to the photovoltaic thermal solar collector. Photovoltaic thermal collector is a special type of solar collector where electricity and heat are produced simultaneously. The electricity produced from the photovoltaic thermal collector is all converted into useful work. The available quantity of the heat collected can readily be determined by taking into account both the quantity (heat quantity) and quality ( a function of temperature) of the thermal energy. Therefore, using the concept of exergy allows heat produced from the thermal collector and the electricity generated from the photovoltaic cells to be compared or to be evaluated on the basis of a common measure such as the effectiveness on solar energy collection or the total amount of available energy. In this paper, the effectiveness of solar energy collection is called combined photovoltaic thermal exergy efficiency. An experimental setup of a double pas photovoltaic thermal solar collector has been deigned, fabricated and tested. (author)

1998-01-01

133

On-orbit solar calibration methods using the Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system: lessons learned  

Science.gov (United States)

The Clouds and Earth's Radiant Energy System (CERES) scanning thermistor bolometers measure earth-reflected solar and earth-emitted long-wave radiances, at the top- of-the-atmosphere. The bolometers measure the earth radiances in the broadband shortwave solar (0.3-5.0 microns) and total (0.3->100 microns) spectral bands as well as in the 8->12 microns water vapor window spectral band over geographical footprints as small as 10 kilometers at nadir. December 1999, the second and third set of CERES bolometers was launched on the Earth Observing Mission Terra Spacecraft. May 2003, the fourth and fifth set of bolometers was launched on the Earth Observing Mission Aqua Spacecraft. Recently, (October 2011) the sixth instrument was launched on the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (Suomi NPP) Spacecraft. Ground vacuum calibrations define the initial count conversion coefficients that are used to convert the bolometer output voltages into filtered earth radiances. The mirror attenuator mosaic (MAM), a solar diffuser plate, was built into the CERES instrument package calibration system in order to define on-orbit shifts or drifts in the sensor responses. It followed a similar design as the Earth Radiation Budget Experiment (ERBE) scanners with improvements from lessons learned. The shortwave and shortwave part of the total-wave sensors are calibrated using the solar radiances reflected from the MAM's. Each MAM consists of baffle-solar diffuser plate systems, which guide incoming solar radiances into the instrument fields of view of the shortwave and total wave sensor units. The MAM diffuser reflecting type surface consists of an array of spherical aluminum mirror segments, which are separated by a Merck Black A absorbing surface, over-coated with SIOx (SIO2 for PFM). Thermistors are located within each MAM plate and the total channel baffle. The CERES MAM is designed to yield calibration precisions approaching .5 percent for the total and shortwave detectors. The Terra FM1 and FM2 shortwave channels and the FM1 and FM2 total channels MAM calibration systems showed shifts in their solar calibrations of 1.5, 2.5, 1.5 and 6 percent, respectively within the first year. The Aqua FM3, and FM4 shortwave channels and the FM3 and FM4 total channels MAM calibration systems showed shifts in their solar calibrations of 1.0, 1.2, 2.1 and .8 percent, respectively within the first year. A possible explanation has attributed the MAM reflectance change to on-orbit solar ultraviolet/atomic oxygen/out-gassing induced chemical changes to the SIOx coated MAM assembly during ram and solar exposure. There is also changes to the sensor telescope shortwave filters as well as the Total channel mirrors and/or sensors. The Soumi NPP FM5 is still after 2.5 years displaying a stability of less than .5 percent. In this presentation, lessons learned from the ERBE MAM and application of knowledge of how the space environment affected the CERES FM1-4 solar calibrations will be presented along with on-orbit measurements for the thirteen years the CERES instruments have been on-orbit.

Wilson, Robert S.; Priestley, Kory J.; Thomas, Susan; Hess, Phillip; Shankar, Mohan; Smith, Nathaniel; Szewczyk, Peter

2013-09-01

134

Solar collector manufacturing activity, 1992  

Energy Technology Data Exchange (ETDEWEB)

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.

1993-11-09

135

Solar collector module  

Energy Technology Data Exchange (ETDEWEB)

A frame is disclosed for supporting a parallel array of a plurality of tubular glass solar energy collectors. A transverse manifold, which extends perpendicularly to all the collector tubes, supports one end of each tube and serves also to direct the flow of the heat transfer fluid through the tubes. The manifold is secured to brackets which in turn are secured to longitudinal structural members. A rigid transverse support member is secured to the ends of the longitudinal structural members and mounts the other end of each tube, permitting preassembly of the glass tubes in the frame and installation on a roof as a module. Tension rods between the brackets and the transverse support member prestress the frame and add rigidity.

Dunlap, G.H.; Zitkus, W.J.

1983-11-08

136

Advanced radiant combustion system. Final report, September 1989--September 1996  

Energy Technology Data Exchange (ETDEWEB)

Results of the Advanced Radiant Combustion System (ARCS) project are presented in this report. This work was performed by Alzeta Corporation as prime contractor under a contract to the U.S. Department of Energy Office of Industrial Technologies as part of a larger DOE program entitled Research Program for Advanced Combustion Systems. The goals of the Alzeta ARCS project were to (a) Improve the high temperature performance characteristics of porous surface ceramic fiber burners, (b) Develop an Advanced Radiant Combustion System (ARCS) that combines combustion controls with an advanced radiant burner, and (c) Demonstrate the advanced burner and controls in an industrial application. Prior to the start of this project, Alzeta had developed and commercialized a porous surface radiant burner, the Pyrocore{trademark} burner. The product had been commercially available for approximately 5 years and had achieved commercial success in a number of applications ranging from small burners for commercial cooking equipment to large burners for low temperature industrial fluid heating applications. The burner was not recommended for use in applications with process temperatures above 1000{degrees}F, which prevented the burner from being used in intermediate to high temperature processes in the chemical and petroleum refining industries. The interest in increasing the maximum use temperature of the burner was motivated in part by a desire to expand the number of applications that could use the Pyrocore product, but also because many of the fluid sensitive heating applications of interest would benefit from the distributed flux characteristic of porous surface burners. Background information on porous surface radiant burners, and a discussion of advantages that would be provided by an improved product, are presented in Section 2.

Sullivan, J.D.; Carswell, M.G.; Long, F.S.

1996-09-01

137

Analysis of feasibility from a amianthus cement tile collector of solar energy; Analise de viabilidade de uma telha coletora de energia solar de cimento amianto  

Energy Technology Data Exchange (ETDEWEB)

This work aimed to develop the idea of joining in a single product a residential roof tile capable of acting simultaneously as a sun radiation collector. In order to do this, a study was accomplished on how the integration of a solar collector to the architectural project of a house occurs, taking into account the various aspects of installation and design. A prototype which uses one of the most common construction materials was projected, built and evaluated for testing the hypothesis. This prototype uses amianthus cement tile, together with copper sheets and pipes, aluminum sheets, glasses and other finishing. The evaluation consisted basically of behaviour analysis of the components when submitted to high work temperatures and measurements taken allowing a first calculation of the prototype efficiency. As a comparison parameter, a plane solar collector sold throughout the country was used. It has a qualifying stamp emitted by the Instituto Nacional de Metrologia, certifying as a high performance equipment. Some experiment results showed that the prototype presented promising efficiency for the project stage, allowing the foreseeing that, with the implementation of the improvements, a compatible efficiency can be reached at lower prices compared to the standard collector. In order to analyse the energetic efficiency, the forced circulation regimen of the working fluid was adopted, with controlled outlet; calculations were taken each five minutes, in the period between 10:00 am. and 2:00 p m, in good insolation days. The input and output temperatures of the fluid in the collector and in the prototypes were measured by means of thermocouples connected to a data acquisition board from a computer exclusively dedicated to this finality. The solar radiation register was obtained by a Kipp-Zonen pyrano meter and the data were stored into a 'data logger' each five minutes, thus establishing a data base, which latter allowed the development of further work through specific software, for the construction of reference tables and graphics. The instantaneous efficiency was obtained by the ratio between the incident energy on the collectors and the useful heat transferred to the circulating fluid. The standard collector presented a efficiency always over 50%, even on low insolation days showing, under certain flow conditions, a high performance, never reached by the prototype, which only in a few situations presented a performance near to the standard (80% compared to the standard collector). (author)

Alencar, Francisco de [UNESP, Bauru, SP (Brazil). Faculdade de Arquitetura, Artes e Comunicacao. Dept. de Desenho Industrial; Saglietti, Jose Roberto Correa [UNESP, Botucatu, SP (Brazil). Inst. de Biociencias. Dept. de Fisica e Biofisica

1999-06-01

138

Radiant vessel auxiliary cooling system  

Science.gov (United States)

In a modular liquid-metal pool breeder reactor, a radiant vessel auxiliary cooling system is disclosed for removing the residual heat resulting from the shutdown of a reactor by a completely passive heat transfer system. A shell surrounds the reactor and containment vessel, separated from the containment vessel by an air passage. Natural circulation of air is provided by air vents at the lower and upper ends of the shell. Longitudinal, radial and inwardly extending fins extend from the shell into the air passage. The fins are heated by radiation from the containment vessel and convect the heat to the circulating air. Residual heat from the primary reactor vessel is transmitted from the reactor vessel through an inert gas plenum to a guard or containment vessel designed to contain any leaking coolant. The containment vessel is conventional and is surrounded by the shell.

Germer, John H. (San Jose, CA)

1987-01-01

139

Heat yield and characteristics of solar collectors  

International Nuclear Information System (INIS)

The results of the EIR collector test series of the summers 1978 and 1979 are presented. In total, there are 37 different collectors available on the Swiss market. The results are compared with those from the IEA (International Energy Agency) of presuggested reference collectors. Test methods are described and also the construction of the test bench. Also, briefly described is a development method for the calculation of gross heat yield from solar collectors. Then the characteristics of the reference collectors in connection with the test periods are considered, and their role in the calculation of results of single collector test series explained. A description of the spectral photometer is given. (A.N.K.)

1980-01-01

140

Preventing static electricity in fabric dust collectors  

Energy Technology Data Exchange (ETDEWEB)

Almost all industrial dusts - in the correct concentrations and when subjected to a strong enough spark - have the capacity to explode. By design, dust collectors maintain a cloud of finely divided particles in suspension. If these particles are combustible, even small electrostatic charges can lead to an explosion. And, the higher the dust concentration, the less energy required for ignition. Static electricity buildup occurs in a dust collector because the dustladen air receives a static charge as it moves through the ductwork and the collector housing. The fabric of a dust collector bag is a very poor conductor (nearly an insulator), thus preventing the dissipation of this static charge.

Godbey, T.

1985-01-10

 
 
 
 
141

Experimental evaluation of attic radiant barriers  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of ASHRAE Research Project 577-RP, Attic Radiant Barrier Systems, an experimental study to evaluate the impact of radiant barrier systems on summer cooling loads in residential buildings. A simulated attic was built inside the entire area of a 24-ft by 12-ft environmental chamber. A total of 72 steady-state experiments were conducted. Roof temperature varied from attic ventilation varied from 0 to 2.0 cfm/ft{sup 2} and nominal R-11 and R-19 insulations were used in the experiments. Three radiant barrier configurations were used: under the roof deck between the rafters, directly over the ceiling insulation, and with no radiant barrier. Additional experiments were conducted to examine the movement of ventilation air inside the attic. The results show reductions in attic heat gains ranging from 17% to 26% with no ventilation and from 24% to 42% when the attic was ventilated. The location of the radiant barrier had little effect on ceiling heat gain. In addition to reducing ceiling heat gains, the radiant barrier mounted under the roof reduced attic temperatures 10 F to 15 F (6 C to 8 C) under typical conditions. The radiant barrier mounted over the ceiling insulation had a lesser effect on attic air temperature. Soffit-to-ridge ventilation was more effective in reducing ceiling heat gains than gable-to-gable ventilation.

Al-Asmar, H.R.; Jones, B.W.; Matteson, D.K. [Kansas State Univ., Manhattan, KS (United States)

1996-11-01

142

Combination solar radiation collector  

Energy Technology Data Exchange (ETDEWEB)

The proposed collector contains a pipeline with a heat carrier which is in contact with a heat absorbing element, in which solar elements are inserted, and two series-connected light transmitting partitions which form a cavity between themsleves and the heat absorbing element. In order to reduce heat losses, the cavity between the partitions is evacuated, and the other cavity is filled with a transparant heat-gathering, chemically-neutral liquid. When using the solar elements with selective coatings there is some degreadation of the electrical characteristics. This is compensated by increasing the efficiency of the thermal energy conversion.

Koltun, M.M.; Garrilova, I.P.; Matveyev, V.P.

1981-07-30

143

Cleaner for Solar-Collector Covers  

Science.gov (United States)

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.

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

1983-01-01

144

Garbage collector interface  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Ive, Anders; Blomdell, Anders; Ekman, Torbjo?rn; Henriksson, Roger; Nilsson, Anders; Nilsson, Klas; Gestega?rd Robertz, Sven

2002-01-01

145

Solar thermal collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A solar thermal collector is a solar collector designed to collect heat by absorbing sunlight. The actuality of sun collectors today is unquestionable. They allow to heat dwellings, industrial, commercial buildings, and also to provide a hot water-supply in them. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/13475

?????, ???????? ?????????; ?????, ???????? ??????????; Mikhno, Svitlana Vasylivna; Trokhimenko, A.

2011-01-01

146

(Hemicylindrical collector. ) Final report  

Energy Technology Data Exchange (ETDEWEB)

A new type of collector that is ''self-orienting'' and has improved heat transfer capability is developed. The solar collector incorporates a hemicylindrical collector surface and protruding hollow, tubular fins and a storage reservoir. Field testing showed that with proper orientation and a clear sunny day, the reservoir temperature can exceed 120/sup 0/F. (BCS)

Hayford, W.H.

1981-10-30

147

Connectable solar air collectors  

Energy Technology Data Exchange (ETDEWEB)

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 applying statistical identification of the parameters characterizing the solar air collectors. The two methods lead to identical steady state efficiencies for the three investigated solar air collectors. The simple method is mainly applicable when comparing efficiencies of different solar air collectors. If simulation of the dynamical behaviour of the solar air collectors is the aim, the advanced method is still needed. (au)

Oestergaard Jensen, S.; Bosanac, M.

2002-02-01

148

Modelling of Microclimate in collectors.  

DEFF Research Database (Denmark)

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 microclimate conditions for materials. Results from the computer model will be compared to measurement of microclimatic parameters in a collector in operation.

Holck, Ole

1996-01-01

149

Radiant cooling in US office buildings: Towards eliminating the perception of climate-imposed barriers  

Energy Technology Data Exchange (ETDEWEB)

Much attention is being given to improving the efficiency of air-conditioning systems through the promotion of more efficient cooling technologies. One such alternative, radiant cooling, is the subject of this thesis. Performance information from Western European buildings equipped with radiant cooling systems indicates that these systems not only reduce the building energy consumption but also provide additional economic and comfort-related benefits. Their potential in other markets such as the US has been largely overlooked due to lack of practical demonstration, and to the absence of simulation tools capable of predicting system performance in different climates. This thesis describes the development of RADCOOL, a simulation tool that models thermal and moisture-related effects in spaces equipped with radiant cooling systems. The thesis then conducts the first in-depth investigation of the climate-related aspects of the performance of radiant cooling systems in office buildings. The results of the investigation show that a building equipped with a radiant cooling system can be operated in any US climate with small risk of condensation. For the office space examined in the thesis, employing a radiant cooling system instead of a traditional all-air system can save on average 30% of the energy consumption and 27% of the peak power demand due to space conditioning. The savings potential is climate-dependent, and is larger in retrofitted buildings than in new construction. This thesis demonstrates the high performance potential of radiant cooling systems across a broad range of US climates. It further discusses the economics governing the US air-conditioning market and identifies the type of policy interventions and other measures that could encourage the adoption of radiant cooling in this market.

Stetiu, C.

1998-01-01

150

Exergy metrication of radiant panel heating and cooling with heat pumps  

International Nuclear Information System (INIS)

Highlights: ? Rational Exergy Management Model analytically relates heat pumps and radiant panels. ? Heat pumps driven by wind energy perform better with radiantpanels. ? Better CO2 mitigation is possible with wind turbine, heat pump, radiant panel combination. ? Energy savings and thermo-mechanical performance are directly linked to CO2 emissions. - Abstract: Radiant panels are known to be energy efficient sensible heating and cooling systems and a suitable fit for low-exergy buildings. This paper points out the little known fact that this may not necessarily be true unless their low-exergy demand is matched with low-exergy waste and alternative energy resources. In order to further investigate and metricate this condition and shed more light on this issue for different types of energy resources and energy conversion systems coupled to radiant panels, a new engineering metric was developed. Using this metric, which is based on the Rational Exergy Management Model, true potential and benefits of radiant panels coupled to ground-source heat pumps were analyzed. Results provide a new perspective in identifying the actual benefits of heat pump technology in curbing CO2 emissions and also refer to IEA Annex 49 findings for low-exergy buildings. Case studies regarding different scenarios are compared with a base case, which comprises a radiant panel system connected to a natural gas-fired condensing boiler in heating and a grid power-driven chiller in cooling. Results show that there is a substantial CO2 emission reduction potential if radiant panels are optimally operated with ground-source heat pumps driven by renewable energy sources, or optimally matched with combined heat and power systems, preferably running on alternative fuels.

2012-11-01

151

Radiant vessel auxiliary cooling system  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an improved radiant vessel passive cooling system for liquid-metal poor-type modular nuclear reactors having a reactor vessel and a surrounding containment vessel spaced apart from the reactor vessel to form a first interstitial region containing an inert gas, the improvement comprising: a shell spaced apart from and surrounding the containment vessel to form a second interstitial region comprising a circulatory air passage. The circulatory air passage has an air inlet at a first position and an air outlet at a second position which is vertically higher than the first position. The second interstitial region lies between the shell and the containment vessel; and surface area extension means in the shell is longitudinally disposed from the shell into the second interstitial region towards the containment vessel to receive thermal radiation from the containment vessel. The surface area extension means is spaced apart from the external surface of the containment vessel where heat radiated form the containment vessel is received at the surface extension means for convection, conduction and radiation to air in the circulatory passage.

Germer, J.H.

1987-07-07

152

Performance of an absorbing concentrating solar collectors  

International Nuclear Information System (INIS)

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

1990-12-10

153

Study of a biogas digester feed in energy by a solar-water heating collector  

International Nuclear Information System (INIS)

The socio-economic development which occurred to the XIXE and XXE centuries would have been impossible without energy. Indeed coal, oil, the nature gas and various other sources of energy were the world engine of the economy. Currently, energy is available in great quantity and remains relatively cheap. It makes it possible to many populations to enjoy very high levels of comfort, productivity and mobility. The access to these great quantities of energy and their exploitation is however unequally distributed between the areas and the countries. In Algeria in spite of the high contents in hydrocarbons, the supply fossil fuels (oil, natural gas) remains one of the major problems of the wedged areas and more particularly the mountainous areas and those of the south, which generated a consumption increased out of wood, a thorough degradation of the forests, an erosion of the grounds and a deterioration of the climate and environment. To meet the requirements in energy for our country, in order to ensure its perennity, to appreciably reduce local pollution and the effect of greenhouse, for the safeguarding of the environment, the prospecting and the development of new sources of energy were in particular undertaken the energy of the biomass and more precisely that provided by biogas. This largely available renewable energy, inexpensive and non-polluting in used to supplement non-renewable fossil energy. Energy production starting from the organic matter of various origins: animal manure, under products of the food industry, mud of the stations of purification, household refuse..., by means of processes of anaerobic digestion in suitable digesters (for bio-methane production), will allow a better management of waste. a safeguarding of the environment and a development as well as a diversification of the energy resources (alternative energies). In addition, this organic matter, at the local level, will make it possible to produce energy at lower cost for cooking. the heating, the lighting and manure with high fertilising potential (stabilised mud) like amendments for the arable lands. The production of biogas could be regarded as an economic solution, decentralised and ecological with these problems through energy autonomy and a durable agricultural development of the rural zones. The bio-methane remains an energy ignored in Algeria, that in spite of several attempts at use which were undertaken since the Forties and even if it does not form part of our sociological cultural and economic traditions, it must represent the best solution to the already mentioned problems. Our study propose to produce bio-methane starting from the animal manure (dung of cows). For that an experimental device was designed and carried out. It consists of digester of 800 litters, of a gas meter bell of 600 litters, of a device of heating applied with a solar-fired heater which ensures a mesophile temperature to him and of a system of agitation of the substrate. The experimental study made it possible to optimize the process of production, for a domestic application and also to develop a system temperature control required at the entry of digester ranging between 25 and 40 degree centigrade. The model is quasi-autonomous. The achievement of this objective of research will make it possible, as we hope for it, to lay down a policy of digester installation of on a national scale.(Author)

2006-01-01

154

Interrelation between mean radiant temperature and room geometry  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Energy saving is one of the most important research directions in the building sector. Daily new HVAC solutions and equipments are developed aiming higher efficiency and lower fossil fuel utilisation. There are cases when only the energy quantity is taken into account and the human side of the problem is neglected. The new energy saving ideas should be analysed from thermal comfort point too. The aim of our research was to see which the influence of the room geometry on the mean radiant tempe...

Kalmár Ferenc (1974-) (gépészmérnök); Kalmár Tünde (1978-) (gépészmérnök)

2012-01-01

155

Integrated solar collector  

Science.gov (United States)

A solar collector having a copper panel in a contiguous space relationship with a condenser-evaporator heat exchanger located under the panel, the panel having a honeycomb-like structure on its interior defining individual cells which are filled with zeolite loaded, in its adsorbed condition, with 18 to 20% by weight of water. The interior of the panel and heat exchanger are maintained at subatmospheric pressure of about 0.1 to 1 psia. The panel and heat exchanger are insulated on their lateral sides and bottoms and on the top of the heat exchange. The panel has a black coating on its top which is exposed to and absorbs solar energy. Surrounding the insulation (which supports the panel) is an extruded aluminum framework which supports a pair of spaced-apart glass panels above the solar panel. Water in conduits from a system for heating or cooling or both is connected to flow into an inlet and discharge from outlet of a finned coil received within the heat exchanger. The collector panel provides heat during the day through desorption and condensing of water vapor from the heated solar panel in the heat exchanger and cools at night by the re-adsorption of the water vapor from the heat exchanger which lowers the absolute pressure within the system and cools the heat exchange coils by evaporation.

Tchernev, Dimiter I. (9 Woodman Rd., Chestnut Hill, MA 02167)

1985-01-01

156

Solar energy in double-pack? Hybrid collectors; Sonne im Doppelpack? Hybridkollektoren  

Energy Technology Data Exchange (ETDEWEB)

The scarce roof space could be utilized more efficient by means of modules which supply electricity as well as thermal energy for the generation of hot water or heating processes. Nethertheless, these solar modules do not harmonize optimally. Thus, the so-called hybrid technology prevails only hesitantly.

Anon.

2012-07-01

157

Comparison of three different collectors for process heat applications  

Science.gov (United States)

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

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

1994-09-01

158

Dynamic performance of parabolic trough solar collector  

Energy Technology Data Exchange (ETDEWEB)

A model is set up to study the dynamic performance of the parabolic trough solar collector (PTC). Instantaneous beam solar radiation, incidence angle of solar beam to collector aperture, tracking angle of collector aperture and distribution of concentrated solar radiation along focal axis can be calculated. The results show that the energy gain and the energy efficiency of the PTC are influenced by parameters such as mass flow rate of working fluid and tube length. The model can be used for optimizing the design of the PTC and predicting the performance of the PTC. (orig.)

Ji Jie; Han Chongwei; He Wei; Pei Gang [Dept. of Thermal Science and Energy Engineering, Univ. of Science and Tech. of China, Hefei (China)

2008-07-01

159

Solar collector. Solarkollektor  

Energy Technology Data Exchange (ETDEWEB)

This invention deals with a solar collector with frame and cover. The cover has been fastened on the edges of the frame. A proposal describes a simple and reliable connection between cover and collector frame. For resolving this fastening problem, the edge of the cover plate has been provided wth clamps. By the use of these clamps with spring systems bore holes in the cover are not needed. On the collector holding frame, originally mounted at the roof of a house, the solar collector could be fastened. In a preferable form of the invention, a gasket between collector holder frame and cover has been used. By the spring of the clamp and gasket a very intensive contact of collector frame and cover could be achieved.

1981-12-18

160

Solar collector test report  

Science.gov (United States)

The commercial readiness and potential of an all plastic solar hot water collector were evaluated. The collector is described and data are given for the efficiency curve, incident angle modifier, raw test data, and static tests. The design demonstrates that a thin film plastic absorber can be built to produce performance at least equal to the mid range of conventional copper or aluminum absorbers and that production costs could be at least half that of currently available collectors.

Stoney, W. E.

1981-06-01

 
 
 
 
161

Effects of High Temperature on Collector Coatings  

Science.gov (United States)

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.

Lowery, J. R.

1982-01-01

162

Reverberatory screen for a radiant burner  

Energy Technology Data Exchange (ETDEWEB)

The present invention relates to porous mat gas fired radiant burner panels utilizing improved reverberatory screens. The purpose of these screens is to boost the overall radiant output of the burner relative to a burner using no screen and the same fuel-air flow rates. In one embodiment, the reverberatory screen is fabricated from ceramic composite material, which can withstand higher operating temperatures than its metallic equivalent. In another embodiment the reverberatory screen is corrugated. The corrugations add stiffness which helps to resist creep and thermally induced distortions due to temperature or thermal expansion coefficient differences. As an added benefit, it has been unexpectedly discovered that the corrugations further increase the radiant efficiency of the burner. In a preferred embodiment, the reverberatory screen is both corrugated and made from ceramic composite material.

Gray, P.E.

1999-11-23

163

Parabolic Concentrating Collector: A Tutorial.  

Science.gov (United States)

A tutorial overview of point-focusing parabolic collectors is presented. Optical and thermal characteristics of such collectors are discussed. Data representing typical achievable collector efficiencies are presented and the importance of balancing collec...

V. C. Truscello

1979-01-01

164

Structurally Integrated Steel Solar Collector.  

Science.gov (United States)

A flat plate solar heat collector unit is described. The solar collector is integrated as a structural unit so that the collector also functions as the building roof. The functions of efficient heat collection, liquid coolant flow passages, roof structura...

S. W. Moore

1977-01-01

165

Evaluación energética de un colector solar de placa plana de doble cubierta / Energy assessment of a double cover flat-plate solar collector  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En este artículo se establece la incidencia de la relación de aspecto (razón entre la longitud y ancho de un colector de área constante) sobre la eficiencia térmica de un colector solar de placa plana que utiliza doble cubierta transparente para el calentamiento de aire. Este estudio se realiza desd [...] e dos enfoques: el primero utiliza un modelo físico-matemático a partir de los balances de energía del colector, y el segundo utiliza un prototipo con su respectiva instrumentación para calcular su rendimiento de manera experimental. El colector está compuesto por una estructura en madera, una doble cubierta de vidrio transparente, una placa absorbedora de radiación solar y un ventilador para extraer el aire calentado. Para calcular el rendimiento se registraron de manera automática datos de temperatura, radiación solar y flujo másico de aire; durante aproximadamente 6 horas por varios días y bajo distintas condiciones climáticas de la ciudad de Montería, Córdoba (Colombia). En general se encontró, para un área constante del colector, que la eficiencia térmica de este aumenta cuando la relación de aspecto aumenta y que el modelo teórico se ajusta de manera aceptable con los resultados experimentales. Abstract in english This study establishes the effect of the aspect ratio (ratio between length and width of a constant collector area) on the thermal efficiency of a flat-plate solar collector that uses a double cover for air heating. The analysis has two approaches: first, using a physical-mathematical model that dev [...] elop a steady state analysis from a collector energy balance and the second, using an instrumented prototype to calculate its performance in experimental way. The collector configuration consists in a wood structure, a double glass cover, an absorber plate of solar radiation and blower to extract the heated air. To calculate the performance temperature data, solar radiation and mass flow of air were automatically recorded for about 6 hours for several days and under different weather conditions in the city of Montería, Cordoba. In general it was found, for a constant collector area, where the thermal efficiency increases when the aspect ratio increases and that the theoretical model fits in an acceptable way with the experimental results.

Adrián Enrique, Ávila Gómez; Jorge Mario, Mendoza Fandiño; Julio Fernando, Beltrán Sarmiento.

166

Intermittent tracking of flat plate collectors  

International Nuclear Information System (INIS)

A theoretical analysis of different intervals of intermittent two-axis tracking of the sun, on the amount of annual energy received by flat-plate collectors, has been carried out. The analysis was done for Ipoh, a city near the university at a latitude of 40 34 North in Malaysia. For the analysis, a computer program was developed to calculate the solar insulation according to the interval settings, considering ASHRAE Standard Sky assumption. Both direct and diffused components of solar radiation have been considered. The tracking system was targeted for flat plate collectors where the degree of tracking accuracy would be much lower Hence, the tracking mechanism will be much simpler and lower in costs. Results showed that by a 3-hour intermittent tracking, a flat-plate collector could get as much as 35% more annual energy than a fixed one. The 3-hour interval tracking greatly simplifies the gear mechanism from the motor to the solar collector. (Author)

1999-06-08

167

Test station for solar collectors in Brazil  

Energy Technology Data Exchange (ETDEWEB)

R + D programmes for the utilization of solar energy are, besides the application of solar collectors for hot water production, aiming at systems operating above 100/sup 0/C. In sunny regions, solar refrigeration and cooling, agricultural and industrial process heat, as well as thermodynamic engines are of special interest. The collectors and their operation under the climatic conditions at the place of a possible application are the key components of such solar systems. Based on the co-operation of the Institut fuer Kernphysik of the KFA Juelich and the Instituto de Fisica of the University of Sao Paulo/Brazil, a collector test station for testing of collector in the temperature range above 100/sup 0/C was developed, installed and put into operation at the site of Atibaia, Sao Paulo/Brazil. Three collector types, installed and operated in a field size of about 20 m/sup 2/ each, provided useful methodical and technical information for comparable projects. The operational collector test station is open for scientific and technical investigations on solar collectors and systems which are of interest for Brazilian and German partner institutions.

Anhalt, J.; Massmeyer, K.; Stein, H.J.

1981-12-01

168

Hydronic radiant cooling: Overview and preliminary performance assessment  

Energy Technology Data Exchange (ETDEWEB)

A significant amount of electrical energy used to cool non-residential buildings is drawn by the fans used to transport the cool air through the thermal distribution system. Hydronic systems reduce the amount of air transported through the building by separating ventilation and thermal conditioning. Due to the physical properties of water, hydronic distribution systems can transport a given amount of thermal energy using less than 5% of the otherwise necessary fan energy. This savings alone significantly reduces the energy consumption and especially the peak power requirement This survey clearly shows advantages for radiant cooling in combination with hydronic thermal distribution systems in comparison with the All-Air Systems commonly used in California. The report describes a literature survey on the system's development, thermal comfort issues, and cooling performance. The cooling power potential and the cooling power requirement are investigated for several California climates. Peak-power requirement is compared for hydronic radiant cooling and conventional All-Air-Systems.

Feustel, H.E.

1993-05-01

169

Hydronic radiant cooling: Overview and preliminary performance assessment  

Energy Technology Data Exchange (ETDEWEB)

A significant amount of electrical energy used to cool non-residential buildings is drawn by the fans used to transport the cool air through the thermal distribution system. Hydronic systems reduce the amount of air transported through the building by separating ventilation and thermal conditioning. Due to the physical properties of water, hydronic distribution systems can transport a given amount of thermal energy using less than 5% of the otherwise necessary fan energy. This savings alone significantly reduces the energy consumption and especially the peak power requirement This survey clearly shows advantages for radiant cooling in combination with hydronic thermal distribution systems in comparison with the All-Air Systems commonly used in California. The report describes a literature survey on the system`s development, thermal comfort issues, and cooling performance. The cooling power potential and the cooling power requirement are investigated for several California climates. Peak-power requirement is compared for hydronic radiant cooling and conventional All-Air-Systems.

Feustel, H.E.

1993-05-01

170

Transpired solar collectors for ventilation air heating  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Transpired solar collectors (TSCs) improve the environmental performance of buildings by preheating incoming ventilation air using solar energy, substituting the need to use fossil fuels. TSCs have been used successfully in the USA and Canada over the past 20 years and have been shown to achieve economic payback of between 2 and 10 years. The economic performance is achieved through a combination of high thermal efficiency and the low cost of the solar collector, which is in the form of a sin...

Hall, R.; Wang, X.; Ogden, R.; Elghali, L.

2011-01-01

171

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the present work, investigations are made to study performance characteristics of solar flat plate collector with different selective surface coatings. Flat plate collector is one of the important solar energy trapping device which uses air or water as working fluid. Of the many solar collector concepts presently being developed, the relative simple flat plate solar collector has found the widest application so far. Its characteristics are known, and compared with other collector types, it...

Madhukeshwara N, E. S. Prakash

2012-01-01

172

Performances and yield assessment of glazed photovoltaic-thermal collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Photovoltaic-Thermal (PV-T) hybrid collectors are multi-energy components that convert solar energy into both electricity and heat. In this paper, the performances of a PV-T collector are investigated. The objective is not only the evaluation of the PV-T collector itself, but the evaluation of this component operating in a real energy system. For this purpose, experimental prototypes of PV-T collector were built, tested in an indoor sun simulator and finally installed and monitored at the EDF...

Dupeyrat, P.; Fortuin, S.; Kwiatkowski, G.; Baranzini, M.; Schumann, M.

2012-01-01

173

Thermal Performance Evaluation of Attic Radiant Barrier Systems Using the Large Scale Climate Simulator (LSCS)  

Energy Technology Data Exchange (ETDEWEB)

Application of radiant barriers and low-emittance surface coatings in residential building attics can significantly reduce conditioning loads from heat flow through attic floors. The roofing industry has been developing and using various radiant barrier systems and low-emittance surface coatings to increase energy efficiency in buildings; however, minimal data are available that quantifies the effectiveness of these technologies. This study evaluates performance of various attic radiant barrier systems under simulated summer daytime conditions and nighttime or low solar gain daytime winter conditions using the large scale climate simulator (LSCS). The four attic configurations that were evaluated are 1) no radiant barrier (control), 2) perforated low-e foil laminated oriented strand board (OSB) deck, 3) low-e foil stapled on rafters, and 4) liquid applied low-emittance coating on roof deck and rafters. All test attics used nominal RUS 13 h-ft2- F/Btu (RSI 2.29 m2-K/W) fiberglass batt insulation on attic floor. Results indicate that the three systems with radiant barriers had heat flows through the attic floor during summer daytime condition that were 33%, 50%, and 19% lower than the control, respectively.

Shrestha, Som S [ORNL; Miller, William A [ORNL; Desjarlais, Andre Omer [ORNL

2013-01-01

174

Internal absorber solar collector  

Science.gov (United States)

Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

Sletten, Carlyle J. (106 Nagog Hill Rd., Acton, MA 01720); Herskovitz, Sheldon B. (88 Hammond St., Acton, MA 01720); Holt, F. S. (46 Emerson Rd., Winchester, MA 01890); Sletten, E. J. (Chestnut Hill Rd. R.F.D. Rte. #4, Amherst, NH 03031)

1981-01-01

175

The modified thermal spike model in materials at irradiation with high energy heavy ions with the radiant function depending on the ion velocity  

International Nuclear Information System (INIS)

At passage of heavy ions through condensed media, their energy losses are generally spent for elastic and inelastic interactions. The SRIM-2008 computer program allows calculating the energy losses of heavy ions at their passage through condensed media. Of great importance for the investigation is the time from the moment of ion's hitting the target to its full stopping. The performed calculations (using the results of the SRIM-2008 program) have shown that the time of passage by a uranium ion with the energy 700 MeV in a nickel target is tion ? 4·10-12 s. In the previous investigations, the motion of an ion in a material was not considered and a source with the action time tion ? 10-14 s was used. In this paper the thermal spike model with a new source considering the motion of an ion within a material is proposed

2009-01-01

176

Toward an Earth Clouds, Aerosols and Radiation Explore (EarthCARE) thermal flux determination: Evaluation using Clouds and the Earth's Radiant Energy System (CERES) true along-track data  

Science.gov (United States)

The Earth Clouds, Aerosols and Radiation Explorer (EarthCARE) mission developed by the European Space Agency and the Japan Aerospace Exploration Agency addresses the need to improve the understanding of the interactions between cloud, aerosol, and radiation processes. The broadband radiometer (BBR) instrument on board the EarthCARE spacecraft provides measurements of broadband reflected solar and emitted thermal radiances at the top of atmosphere (TOA) over the along-track satellite path at three fixed viewing zenith angles. The multiangular information provided by the BBR, combined with the spectral information from the EarthCARE's multispectral imager (MSI) can be exploited to construct accurate thermal radiance-to-flux conversion algorithms on the basis of radiative transfer modeling. In this study, the methodology to derive longwave (LW) fluxes from BBR and MSI data is described, and the performance of the LW BBR angular models is compared with the Clouds and the Earth's Radiant Energy System (CERES) Terra flux retrievals in order to evaluate the reliability of the BBR synthetic models when applied to satellite-based radiances. For this purpose, the BBR methodology proposed in this work is adapted to the CERES and the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument specifications, and new LW angular models for CERES are developed. According to plane-parallel simulations, the BBR LW flux uncertainty caused by flux inversion could be reduced up to 0.4 W m-2. The intercomparison between CERES BBR-like adapted and CERES original angular models is performed over a BBR-like database of CERES true along track, and the averaged instantaneous retrievals agree to within 2 W m-2.

Domenech, C.; Wehr, T.; Fischer, J.

2011-03-01

177

Prelaunch Calibrations of the Clouds and the Earth's Radiant Energy System (CERES) Tropical Rainfall Measuring Mission and Earth Observing System Morning (EOS-AM1) Spacecraft Thermistor Bolometer Sensors  

Science.gov (United States)

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometer sensors measure earth radiances in the broadband shortwave solar (O.3 - 5.0 micron and total (0.3 to 100 microns) spectral bands as well as in the 8-12 microns water vapor window spectral band. On November 27, 1997, the launch of the Tropical Rainfall Measuring Mission (TRMM) spacecraft placed the first set of CERES sensors into orbit, and 30 days later, the sensors initiated operational measurements of the earth radiance fields. In 1998, the Earth Observing System morning (EOS-AM1) spacecraft will place the second and third sensor sets into orbit. The prelaunch CERES sensors' count conversion coefficients (gains and zero-radiance offsets) were determined in vacuum ground facilities. The gains were tied radiometrically to the International Temperature Scale of 1990 (ITS-90). The gain determinations included the spectral properties (reflectance, transmittance, emittance, etc.) of both the sources and sensors as well as the in-field-of-view (FOV) and out-of-FOV sensor responses. The resulting prelaunch coefficients for the TRMM and EOS-AM1 sensors are presented. Inflight calibration systems and on-orbit calibration approaches are described, which are being used to determine the temporal stabilities of the sensors' gains and offsets from prelaunch calibrations through on-orbit measurements. Analyses of the TRMM prelaunch and on-orbit calibration results indicate that the sensors have retained their ties to ITS-90 at accuracy levels better than /- 0.3% between the 1995 prelaunch and 1997 on-orbit calibrations.

Lee, Robert B., III; Barkstrom, Bruce R.; Bitting, Herbert C.; Crommelynck, Dominique A. H.; Paden, Jack; Pandey, Dhirendra K.; Priestley, Kory J.; Smith, G. Louis; Thomas, Susan; Thornhill, K. Lee; Wilson, Robert S.

1998-01-01

178

Triangular solar collector  

Energy Technology Data Exchange (ETDEWEB)

A solar collector is provided having a substantially triangular-shaped housing defined by a base and a pair of converging side walls. The housing of the collector includes an outlet adjacent the top of the housing, an inlet, a central area and a pair of outer end areas. The problem of stagnation of air in the outer end areas is solved by providing barrier means adjacent the side walls for creating air ducts connecting the outer end areas to the outlet. The intake air is distributed along the base of the collector by an inverted t-shaped air distributor means.

Shea, H.J.

1983-06-21

179

Data collection and performance reporting specifications for solar energy projects: A report of Task VI: The performance of solar heating, cooling, and hot water systems using evacuated collectors  

Energy Technology Data Exchange (ETDEWEB)

This report details the data collection and performance reporting specifications for solar energy projects that were developed by the International Energy Agency Task on the Performance of Solar Heating, Cooling and Hot Water Systems Using Evacuated Collectors. It was developed so that the Task Participants could exchange and present information about individual installations, their operating characteristics and performance results in an accurate and consistent manner. One of the main objectives of the effort was to ensure accurate collection and reporting of data, facilitating analysis and exchange of information among the participants. This document is based on the 1980 International Energy Agency document on reporting format which has been considerably revised. Specific requirements concerning the preparation of diagrams, figures, plots and textural material have evolved permitting more detailed comparisons and exchanges of information among installations. Format requirements include both simulated and measured data.

Chandrashekar, M.; Vanoll, K.H.

1986-06-01

180

Subjective evaluation of different ventilation concepts combined with radiant heating and cooling  

DEFF Research Database (Denmark)

Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation and radiant heating/cooling systems. Two test setups simulated a room in a low energy building with a single occupant during winter. The room was equipped either by a ventilation system supplying warm air space heating or by a combination of radiant floor heating and mixing ventilation system. Next two test setups simulated an office room with two occupants during summer, ventilated and cooled by a single displacement ventilation system or by a radiant floor cooling combined with displacement ventilation. Vertical air temperature distribution was more uniform for floor heating than for warm air heating, but there was no significant difference in thermal perception between the two mixing ventilation systems. For the summer conditions the subjects voted warmer than predicted by the PMV and about one third preferred more air movement. No significant difference in thermal perception between the two displacement ventilation systems was found.

Krajcik, Michal; Tomasi, Roberta

2012-01-01

 
 
 
 
181

SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2008-08-01

182

High temperature flat plate solar collector  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1981-04-01

183

Electrostatic radioactive particle collector  

International Nuclear Information System (INIS)

The facility includes an electrostatic field source whose outlets are connected to a collector electrode and a repulsive electrode and which is accommodated in an insulating casing in a manner such that the electrodes remain uncovered, partly at least. The electrostatic field source can be a capacitor or a formed electret; alternatively, voltage can be brought from an external source. The detector itself can serve as the collector electrode. The electrostatic collector is placed where the volume concentration of radioactive particles is to be measured. The radioactivity collected can be measured over a chosen period of collection by transferring the collector electrode to the detector, or continuously by collecting the radioactive particles directly onto the detector window or onto a thin electrode covering the window. (M.D.). 2 figs

1994-05-31

184

Residential overhead hydronic radiant heating system  

Energy Technology Data Exchange (ETDEWEB)

Project to determine and implement the modifications necessary to adapt a commercial overhead hydronic radiant heating system for use in residential applications. The system, as manufactured by Frenger Canada Inc., has proven successful in commercial and institutional markets and its modification to residential use could add a new market segment to the company`s operation while providing an alternative approach to heating for builders, designers, and homeowners. Project work included an industry survey to determine the acceptable requirements for the system in the residential marketplace; design work that incorporated the requirements of the industry survey and addressed the relevant peculiarities of residential construction; product testing to determine the physical acceptability of the radiant panel selected for residential applications; and economic analysis to ensure costs would not prohibit the marketing of the system in the residential environment. The work was carried out from September 1992 to January 1994.

NONE

1994-12-31

185

Improved radiant burner material. Final report  

Energy Technology Data Exchange (ETDEWEB)

Under DOE/ERIP funds were made available to Superkinetic, Inc. for the development of an improved radiant burner material. Three single crystal ceramic fibers were produced and two fiber materials were made into felt for testing as radiant burner screens. The materials were alpha alumina and alpha silicon nitride. These fibers were bonded with a high temperature ceramic and made into a structurally sound trusswork like screen composed of million psi fiber members. These screens were about 5% solid for 95 porosity as needed to permit the flow of combustable natural gas and air mixture. Combustion test proved that they performed very satisfactory and better than the current state of art screen and showed no visable degrade after testing. It is recommended that more time and money be put into expanding this technology and test these new materials for their maximum temperature and durability for production applications that require better burner material.

Milewski, J.V.; Shoultz, R.A.; Bourque, M.M.; Milewski, E.B. [and others

1998-01-01

186

Solar plastic collectors  

Energy Technology Data Exchange (ETDEWEB)

Several plastic materials are suitable for solar collectors because of their light weight, their high solar transmission, and their resistance to shattering. Additives are needed to make them more weather-resistant, however, and their low fire resistance is a serious drawback. Comparisons of the relative merits of plastics and conventional materials for each of the components are used to rate various collectors in terms of price and efficiency. 4 figures, 3 tables. (DCK)

Bansal, N.K.

1983-07-01

187

Analysis of A Screen Type Solar Air Collector Without Transparent Cover  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The performance of a screen type solar air collector of different uniform mesh sizes and without a glass cover is investigated theoretically. Formulation of simultaneous radiation and convection heat transfer for a semi-steady condition in an isotropic, absorbing set of wire screens is presented. Both colimated and diffuse radiant heat fluxes are incident on the screens, causing absorption, reflection (scattering), emission and heating, the screens, which in turn heat the circulated air flowi...

1989-01-01

188

Non-warping radiant burner construction  

Energy Technology Data Exchange (ETDEWEB)

Applied primarily in the textile industry for drying moving webs of fabric, an improved infrared radiant burner will not warp and cause an uneven heating effect. The edges of the refractory matrix are beveled to allow a wedge of refractory material - in combination with holding clips and a high-temperature adhesive - to hold the matrix to the burner box. By thus avoiding the use of a heat-absorbing retaining rim, the design prevents distortion of the burner-box frame.

Bishilany, W.J. III; Buehl, A.L.; Zwipf, W.H.

1981-03-10

189

Radiant tube technology [steam generation]: executive summary  

Energy Technology Data Exchange (ETDEWEB)

Efficiencies of steam raising apparatus has been slowly increasing over the last two hundred years. There is still a need to increase the efficiencies of steam raising in order to conserve fuel and reduce greenhouse gases, (e.g. to ensure that maximum use is made of the carbon content of natural gas), and there is also a need to reduce the size and cost of the equipment per given use of steam production to conserve industrial space and gain production efficiencies. This project explored the need to increase the efficiencies of steam raising in order to conserve fuel and help reduce greenhouse gases. The document summarizes the use of radiant tubes or candles as a way of burning natural gas with increased radiant efficiency. The project demonstrated that up to 49 percent of radiant efficiencies could be achieved in sub-surface burners. Further work on the reliability of the burners now needs to be undertaken to offer boiler manufacturers an Australian gas fired alternative to present systems.

Clarke, M. `and others` [M.E.T.T.S. Pty. Ltd., Potts Point, NSW (Australia)

1996-10-01

190

16 CFR 1209.6 - Test procedures for critical radiant flux.  

Science.gov (United States)

...specimen. The total heat flux transducer used...conjunction with the dummy specimen should be...output of the total heat flux transducer during...will operate at a no load voltage of 40 volts... (e) Radiant heat energy flux profile... (1) Mount the dummy specimen in the...

2010-01-01

191

Absolute radiant power measurement of the X-ray free-electron laser at SACLA  

International Nuclear Information System (INIS)

The Japanese hard X-ray free-electron laser (XFEL), SACLA (SPring-8 Angstrom Compact free-electron LAser), reached laser amplification at 10 keV photon energy in June 2011. SACLA can provide XFELs with its wavelength of shorter than 0.1 nm. Since the radiant power is a fundamental parameter of the XFEL beam which strongly influences nonlinear effects, its measurement in absolute terms is of significant importance. In the present study, the absolute radiant power of the XFEL was measured using a cryogenic radiometer at the BL3 in SACLA. The radiant power as a function of a silicon attenuator thickness was also measured to estimate the contribution of the higher harmonics. The radiant power in the range between 8 ?W and 1005 ?W was measured in the photon energies of 4.4 keV, 5.8 keV, 9.6 keV, 13.6 keV and 16.8 keV. The contribution of the higher harmonics is negligible except for the photon energy of 4.4 keV. The third harmonics component in the photon energy of 4.4 keV is about 1 %.

2013-03-22

192

Absolute radiant power measurement of the X-ray free-electron laser at SACLA  

Science.gov (United States)

The Japanese hard X-ray free-electron laser (XFEL), SACLA (SPring-8 Angstrom Compact free-electron LAser), reached laser amplification at 10 keV photon energy in June 2011. SACLA can provide XFELs with its wavelength of shorter than 0.1 nm. Since the radiant power is a fundamental parameter of the XFEL beam which strongly influences nonlinear effects, its measurement in absolute terms is of significant importance. In the present study, the absolute radiant power of the XFEL was measured using a cryogenic radiometer at the BL3 in SACLA. The radiant power as a function of a silicon attenuator thickness was also measured to estimate the contribution of the higher harmonics. The radiant power in the range between 8 ?W and 1005 ?W was measured in the photon energies of 4.4 keV, 5.8 keV, 9.6 keV, 13.6 keV and 16.8 keV. The contribution of the higher harmonics is negligible except for the photon energy of 4.4 keV. The third harmonics component in the photon energy of 4.4 keV is about 1 %.

Tanaka, Takahiro; Kato, Masahiro; Kurosawa, Tadahiro; Saito, Norio; Kudo, Togo; Tono, Kensuke; Yabashi, Makina; Ishikawa, Tetsuya

2013-03-01

193

ADVANCED HYBRID PARTICULATE COLLECTOR  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2000-12-01

194

Solar collector design with respect to moisture problems  

DEFF Research Database (Denmark)

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 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.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 more ventilation openings should be made and what influence the insulation material has. Guidelines forcollector designers are proposed. The design guidelines provide some suggestions to be considered during the design of solar collectors.The work was carried out within the framework of the working group Materials in Solar Thermal Collectors of the International Energy Agency-Solar Heating and Cooling Programme.

Holck, Ole; Svendsen, Svend

2003-01-01

195

Radiant solid phase decomposition studies. Technical status report  

Energy Technology Data Exchange (ETDEWEB)

In this report, recent results of research concerned with fundamental studies of the high temperature solid phase decomposition of zinc sulfate at low and high heating rates are presented. The low heating rate studies were carried out using a conventional thermogravimetric system (Setaram Simultaneous TGA/DTA unit). The high heating rate results were obtained in a novel, Fast-TGA system capable of rapidly weighing materials exposed to concentrated radiant energy derived from an arc image furnace. The goal of this work is to identify unique effects of radiant heating on the decomposition behavior of zinc sulfate. This report presents a set of low heating rate results and compares them to those of other investigators. While the fundamental low heating rate studies of solid phase decomposition using conventional thermal analysis systems is now routine, very few instruments are currently available to study these processes under high temperature (>2000/sup 0/C), high radiative flux (up to 1000 W/cm/sup 2/) environments similar to that of a solar furnace. Typical decomposition results obtained from intense radiative heating of zinc sulfate are presented and discussed in conjunction with the design of a novel thermogravimetric system.

T-Raissi, A.

1985-06-01

196

Development of a model to simulate the performance of hydronic radiant cooling ceilings  

Energy Technology Data Exchange (ETDEWEB)

A significant amount of the electrical energy used to cool non-residential buildings equipped with all-air systems is drawn by the fans that transport the cool air through the thermal distribution system. Hydronic radiant cooling systems have the potential to reduce the amount of air transported through the building by separating the tasks of ventilation and thermal conditioning. Because of the physical properties of water, hydronic radiant cooling systems can transport a given amount of thermal energy using less than 5170 of the otherwise necessary fan energy. This improvement alone significantly reduces the energy consumption and peak power requirement of the air conditioning system. Hydronic radiant cooling systems have been used for more than 30 years in hospital rooms to provide a draft-free, thermally stable environment. The energy savings and peak-load characteristics of these systems have not yet been analyzed systematically. Moreover, adequate guidelines for design and control of these systems do not exist. This has prevented their widespread application to other building types. The evaluation of the theoretical performance of hydronic systems could be made most conveniently by computer models. Energy analysis programs such as DOE-2 do not have the capability to simulate hydronic radiant systems yet. In this paper the development of a model that can simulate accurately the dynamic performance of hydronic radiant cooling systems is described. The model is able to calculate loads, heat extraction rates, room air temperature and room surface temperature distributions, and can be used to evaluate issues such as thermal comfort, controls, system sizing, system configuration and dynamic response. The model was created with the Simulation Problem Analysis and Research Kernel (SPARK) developed at the Lawrence Berkeley Laboratory, which provides a methodology for describing and solving the dynamic, non-linear equations that correspond to complex physical systems.

Stetiu, C.; Feustel, H.E.

1995-06-01

197

Theoretical Analysis of Solar Thermal Collector with a Flat Plate Bottom Booster Reflector  

Directory of Open Access Journals (Sweden)

Full Text Available

A theoretical analysis of a solar thermal collector with a flat plate bottom reflector is presented. The bottom reflector extends from the lower edge of the collector. The variations of daily solar radiation absorbed on the collector with inclinations from horizontal for both the collector and reflector throughout the year were predicted, and the optimum inclinations of the collector and reflector which maximize the daily solar radiation absorbed on the collector were determined for each month at 30oN latitude. The effects of the size of the collector and reflector on the daily solar radiation absorbed on the collector were also investigated. The optimum collector inclination is lower in summer and higher in winter, while the optimum reflector inclination is higher in summer and lower in winter. The average daily solar radiation absorbed on the collector throughout the year can be increased about 20%, 27% and 33% by using a bottom reflector if the ratio of reflector length to collector length is 0.5, 1.0 and 2.0, respectively, when the collector’s length is equal to its width.

 Key words: Solar energy; Solar thermal collector; Bottom reflector; Collector-reflector; Optimum inclination

Hiroshi Tanaka

2011-12-01

198

Simulation Application for Optimization of Solar Collector Array  

Directory of Open Access Journals (Sweden)

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.

Igor Shesho*,

2014-01-01

199

The radiant of the Leonids meteor storm in 2001  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have measured the radiant of the Leonids meteor storm in November 2001 by using new observational and analysis techniques. The radiant was measured as the intersections of lines which were detected and extrapolated from images obtained at a single observing site (Akeno Observatory, Japan). The images were obtained by two sets of telephoto lenses equipped with cooled CCD cameras. The measured radiant, (R.A., Dec.)=(154$^\\circ$.35, 21$^\\circ$.55) (J2000), is found to be in ...

Torii, Ken Ichi; Kohama, Mitsuhiro; Yanagisawa, Toshifumi; Ohnishi, Kouji

2002-01-01

200

High-performance vacuum tubes for more energy efficiency. Building-integrated CPC vacuum tube collectors unite several functions.; Hochleistungs-Vakuumroehren fuer mehr Energieeffizienz. Gebaeudeintegrierte CPC-Vakuumroehren-Kollektoren vereinen mehrere Funktionen  

Energy Technology Data Exchange (ETDEWEB)

The performance of solar collectors primarily contributes to increased efficiency and reduced operating costs of solar thermal systems. With the use of building-integrated CPC vacuum tube collectors an extremely high energy yield is achieved on a smaller collector gross area. As a building-integrated system solution the CPC facade provide panels in addition to its use as spandrel panels within the glazed buildings not only an architectural design element, but unite as a multifunctional component for several functions. [German] Die Leistungsfaehigkeit der Solarkollektoren traegt primaer zur Effizienzsteigerung und Reduzierung der Betriebskosten einer Solarthermieanlagen bei. Mit dem Einsatz gebaeudeintegrierter CPC-Vakuumroehrenkollektoren wird auf einer kleineren Kollektorbruttoflaeche ein extrem hoher Energieertrag erreicht. Als gebaeudeintegrierte Systemloesung bieten die CPC-Fassadenkollektoren neben dem Einsatz als Bruestungselemente auch innerhalb der verglasten Gebaeuden nicht nur ein architektonisches Gestaltungselement, sondern vereinen als multifunktionaler Bestandteil noch mehrere Funktionen.

Theiss, Eric

2013-10-15

 
 
 
 
201

Improvement in Clouds and the Earth's Radiant Energy System/Surface and Atmosphere Radiation Budget Dust Aerosol Properties, Effects on Surface Validation of Clouds and Radiative Swath  

Energy Technology Data Exchange (ETDEWEB)

Within the Clouds and the Earth's Radiant Energy System (CERES) science team (Wielicki et al. 1996), the Surface and Atmospheric Radiation Budget (SARB) group is tasked with calculating vertical profiles of heating rates, globally, and continuously, beneath CERES footprint observations of Top of Atmosphere (TOA) fluxes. This is accomplished using a fast radiative transfer code originally developed by Qiang Fu and Kuo-Nan Liou (Fu and Liou 1993) and subsequently highly modified by the SARB team. Details on the code and its inputs can be found in Kato et al. (2005) and Rose and Charlock (2002). Among the many required inputs is characterization of the vertical column profile of aerosols beneath each footprint. To do this SARB combines aerosol optical depth information from the moderate-resolution imaging spectroradiometer (MODIS) instrument along with aerosol constituents specified by the Model for Atmosphere and Chemical Transport (MATCH) of Collins et al. (2001), and aerosol properties (e.g. single scatter albedo and asymmetry parameter) from Tegen and Lacis (1996) and OPAC (Hess et al. 1998). The publicly available files that include these flux profiles, called the Clouds and Radiative Swath (CRS) data product, available from the Langley Atmospheric Sciences Data Center (http://eosweb.larc.nasa.gov/). As various versions of the code are completed, publishable results are named ''Editions.'' After CRS Edition 2A was finalized it was found that dust aerosols were too absorptive. Dust aerosols have subsequently been modified using a new set of properties developed by Andy Lacis and results have been released in CRS Edition 2B. This paper discusses the effects of changing desert dust aerosol properties, which can be significant for the radiation budget in mid ocean, a few thousand kilometers from the source regions. Resulting changes are validated via comparison of surface observed fluxes from the Saudi Solar Village surface site (Myers et al. 1999), and the E13 site at the Atmospheric Radiation Measurement (ARM), Southern Great Plains (SGP) central facility.

Rutan, D.; Rose, F.; Charlock, T.P.

2005-03-18

202

Selective optical coatings for solar collectors  

Science.gov (United States)

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.

Lowery, J. R.

1980-01-01

203

Impact of surface characteristics on radiant panel output  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the experimental results of a research project conducted to determine the impact of surface characteristics on radiant panel output. The hemispherical and angular emittance and radiant panel output were measured for various modern building materials. The surfaces were found to have uniformly high hemispherical emittances and could be considered diffuse emitters. An office-sized environmental chamber was used to test radiant ceiling, floor, and wall panels under both natural and forced convection conditions. The results of these experiments showed that for the surfaces and conditions tested, surface texture did not have a significant impact on the rate of heat transfer from the radiant panels.

Lindstrom, P.C.; Fisher, D.E.; Pedersen, C.O. [Univ. of Illinois, Urbana, IL (United States)

1998-10-01

204

Solar Heating Systems with Evacuated Tubular Solar Collector  

DEFF Research Database (Denmark)

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

Qin, Lin; Furbo, Simon

1998-01-01

205

Electromagnetic Spectrum: Distribution of Radiant Energies  

Science.gov (United States)

This item is a beginning tutorial on the electromagnetic spectrum designed for students of introductory physics. It provides multiple plots of the spectrum to aid users in understanding various EM spectrum classifications. This item is part of a larger tutorial on the topic of Remote Sensing, sponsored by the NASA Goddard Program office.

Short, Nicholas M.

2008-06-12

206

Exergy delivery from typical solar collectors  

Energy Technology Data Exchange (ETDEWEB)

The long term exergy output was calculated for four types of solar collectors located in Sevilla and operating at 50/sup 0/C, 70/sup 0/C and 200/sup 0/C. The performance model PROSOL (1) has been used to predict the long term energy output for several collector types. We point out that a parallelism exists between the energy and exergy graphs through the year. The daytime ambient temperature has a very important influence on the exergy delivery at Sevilla when the temperature of working fluid is low.

Canada, J.; Hernandez, V.R.

1987-01-01

207

Solar radiation collector and concentrator  

Energy Technology Data Exchange (ETDEWEB)

A device is described for concentrating solar radiation upon the surface of a helicoidal tube assembly containing a circulating heat transfer medium whereby the energy of said radiation may be collected and utilized. The device consists of a rectangular container wherein is supported a longitudinal plurality of aligned curved reflectors for gathering and concentrating incident solar radiation, multiple vertical reflectors to gather low-angle radiation, a convex radiation concentrating reflector beneath said helicoidal tube and a means for damping excess solar radiation. A method is given for the utilization of said solar radiation collector whereby the heated circulating medium provides the means for heating and cooling buildings.

Hockman, V.J.

1976-06-22

208

Current collector for AMTEC  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an electrode for an alkali metal thermoelectric converter. It comprises: a body of solid, microcrystalline, ceramic electrolyte capable of transporting sodium ions from a first surface to a second surface; a film of a first metal applied to one of the surfaces. The metal being non-volatile at a temperature up to 1300K and including an early transition metal; and an open, metal current collector grid applied to the film. The metal of the current collector having a coefficient of thermal expansion greater than that of the solid electrolyte, and a restraining element covering the open grid.

Williams, R.M.

1989-10-03

209

Performance evaluation of radiant baseboards (skirtings) for room heating – An analytical and experimental approach  

International Nuclear Information System (INIS)

The aim of this study was to investigate the thermal performance of the hydronic radiant baseboards currently used for space heating in built environments. The presently available equations for determination of heat outputs from these room heaters are valid for a certain height at a specific temperature range. This limitation needed to be addressed as radiant baseboards may be both energy and cost efficient option for space heating in the future. The main goal of this study was therefore to design an equation valid for all baseboard heights (100–200 mm) and excess temperatures (9–60 °C) usually used in built environments. The proposed equation was created by curve fitting using the standard method of least squares together with data from previous laboratory measurements. It was shown that the predictions by the proposed equation were in close agreement with reported experimental data. Besides, it was also revealed that the mean heat transfer coefficient of the investigated radiant baseboards was about 50% higher than the mean heat transfer coefficient of five conventional panel radiators of different types. The proposed equation can easily be used or programed in energy simulation codes. Hopefully this will help engineers to quantify more accurately the energy consumption for space heating in buildings served by radiant baseboards. -- Highlights: • Thermal performance of radiant baseboards (RBs) used for space heating was analyzed. • The proposed heat output equation can be used with confidence for RBs heaters. • The heat transfer ability of RBs was 50% higher than that of panel radiators. • The heat emission from RBs increased by roughly 2.1% per centimeter of height. • The RBs of maximum height should be used for water supply temperatures below 45 °C

2014-01-25

210

New Integrated Solar Collector Design.  

Science.gov (United States)

A new design for a thermal solar collector has been invented, which represents an essential improvement in the cost-benefit ratio compared to other commercially available solar collectors. (ERA citation 11:013129)

M. Mehlen J. Skjaeret J. Rekstad

1984-01-01

211

16 CFR 1209.6 - Test procedures for critical radiant flux.  

Science.gov (United States)

... Test procedures for critical radiant flux. 1209.6 Section 1209.6 Commercial... Test procedures for critical radiant flux. This section provides the test procedure for determining the critical radiant flux of exposed attic floor insulation...

2010-01-01

212

Attic radiant barrier systems: a sensitivity analysis of performance parameters  

Energy Technology Data Exchange (ETDEWEB)

During the past seven years, the Florida Solar Energy Centre (FSEC) has conducted extensive experimental research on radiant barrier systems (RBS). This paper presents recent research on the development of mathematical attic models and results from a sensitivity analysis of RBS performance parameters. Two levels of modelling capability have been developed. A very simplified model based on ASHRAE procedures is used to study the sensitivity of RBS performance parameters, and a very detailed finite-element model is used to study highly complex phenomena, including moisture adsorption and desorption in attics. The speed of the simple model allows a large range of attic parameters to be studied quickly, and the finite-element model provides a detailed understanding of combined heat and moisture transport in attics. (author).

Fairey, P.; Swami, M. (Florida Solar Energy Center, Cape Canaveral, FL (United States))

1992-01-01

213

Sheldon Jackson the Collector.  

Science.gov (United States)

Missionary, educator, humanitarian, and collector, the Reverend Sheldon Jackson came to Alaska in 1877 to assimilate Native populations into the dominant White culture, but his collecting efforts between 1877 and 1902 represent a significant effort to preserve the legacy of Alaska Natives during a period of tumultuous change. A zealous missionary,…

Carlton, Rosemary

214

Spatial distribution and temporal variability of solar radiant over southern Thailand  

Energy Technology Data Exchange (ETDEWEB)

The potential for solar energy in Thailand has been estimated at over 50,000 MW for power generation. However, existing power plants in the country produce only 32 MW. Most the the systems have been installed in rural areas, islands and other off-grid sites. The availability and variability of global solar radiant intensity and its spatial distribution are key parameters for designing and testing outdoor solar energy systems. These parameters must be well understood in order to evaluate system efficiency at specific locations. Therefore, this study examined the spatial distribution and temporal variability of solar radiant over southern Thailand using the Surfer computer program. The incident of solar radiation on a horizontal plane was estimated at 14 synoptic stations using the Angstrom's correlation which was obtained from meteorological data. Rainfall quantity at 3 main meteorological stations was used to correlate the hours of sunshine and to predict them in meteorological stations where sunshine recorders were absent but where rainfall data were present. The 3 stations were at the Surat Thani, Phuket and Hat Yai airports. Angstrom's correlation coefficients were obtained using the correlation between the hours of sunshine and day length. The solar radiant was obtained once the extraterrestrial solar radiation was known. The study showed that the solar radiant over southern Thailand varies between 12.51 to 24.54 MJ per m{sup 2} per day. It was concluded that the temporal variation of solar radiant over southern Thailand is highly influenced by the North-East and South-West monsoons. 16 refs., 1 tab., 17 figs.

Waewsak, J.; Chancham, C. [Thaksin Univ., Phatthalung (Thailand). Dept. of Physics, Renewable Energy System Research and Demonstration Center, Solar and Wind Energy Research Lab

2009-07-01

215

A RADIANT AIR-CONDITIONING SYSTEM USING SOLAR-DRIVEN  

Directory of Open Access Journals (Sweden)

Full Text Available Every air-conditioning system needs some fresh air to provide adequate ventilation air required to remove moisture, gases like ammonia and hydrogen sulphide, disease organisms, and heat from occupied spaces. However, natural ventilation is difficult to control because urban areas outside air is often polluted and cannot be supplied to inner spaces before being filtered. Besides the high electrical demand of refrigerant compression units used by most air-conditioning systems, and fans used to transport the cool air through the thermal distribution system draw a significant amount of electrical energy in comparison with electrical energy used by the building thermal conditioning systems. Part of this electricity heats the cooled air; thereby add to the internal thermal cooling peak load. In addition, refrigerant compression has both direct and indirect negative effects on the environment on both local and global scales. In seeking for innovative air-conditioning systems that maintain and improve indoor air quality under potentially more demanding performance criteria without increasing environmental impact, this paper presents radiant air-conditioning system which uses a solar-driven liquid desiccant evaporative cooler. The paper describes the proposed solar-driven liquid desiccant evaporative cooling system and the method used for investigating its performance in providing cold water for a radiant air-conditioning system in Khartoum (Central Sudan. The results of the investigation show that the system can operate in humid as well as dry climates and that employing such a system reduces air-conditioning peak electrical demands as compared to vapour compression systems.

S. A. ABDALLA

2006-12-01

216

The influence of climate and location on collector performance  

Energy Technology Data Exchange (ETDEWEB)

The influence of annual climate variations on the performance of solar thermal collectors in the northern part of Europe has been investigated. The annual solar collector energy output has been calculated with the MINSUN simulation program using hourly, measured climatic data for the years 1983-98 for three cities situated in the south (Lund), central (Stockholm) and north (Lulea) of Sweden. A synthetic year created with the Meteonorm weather simulation program was also used in the simulations. Two solar thermal collectors were modelled: a flat plate solar collector and a tubular vacuum collector, both of commercial standard. The thermal energy output is strongly correlated to the annual global irradiation at a horizontal surface. The annual average energy delivered from the flat plate collector was 337 kWh/m{sup 2} for Stockholm (337 for Lund and 298 for Lulea), and from the vacuum tube collector 668 kWh/m{sup 2} for Stockholm (675 for Lund and 631 for Lulea) at an operating temperature of T = 50{sup o}C. Maximum deviations from the average value for this 16-year period are around 20% for the flat plate and 15% for the vacuum tube collector, at T=50{sup o}C. The relation between global irradiation on a horizontal surface and the annually collected thermal energy at a constant operating temperature could be fitted to a linear equation: q{sub u} = aG(0{sup o}) + bT, where q{sub u} is the energy output from the collector, G(0{sup o}) the global irradiation at a horizontal surface, T the average temperature of the collector fluid, and a and b fitting parameters in a double linear regression analysis. (author)

Adsten, M.; Waeckelgard, E. [Uppsala University (Sweden). The Angstrom Laboratory; Perers, B. [Vattenfall Utveckling AB, Nykoeping (Sweden)

2002-04-01

217

Literature survey of concentrating solar collectors  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a detailed literature survey of various types of low and intermediate temperature concentrating collectors. The survey includes a Patent search (mostly novel concentrators) and examines the progress in the area of concentrating collectors since 1978. This is the first part of a two part study. Part two will deal with flat plate collectors. Review of the published literature shows a considerable decline in solar energy research in the 80`s, directly related to a decline in general research and development support for alternative energy. Most of the recent significant developments have been in the area of high temperature systems and power towers. The objective of this survey is to summarize developments in the area of low to intermediate temperature collectors and provide this information in an organized manner. The authors will trace the progress of work done since the energy crisis of the seventies and examine what can be done to renew interest in solar energy collection. This is especially relevant now that the world`s attention is being increasingly focused on the environment. High temperature central receiver systems, for electric power generation, will be briefly discussed.

Imadojemu, H.E. [Pennsylvania State Univ., Middletown, PA (United States). School of Science, Engineering and Technology

1995-11-01

218

A test program for solar collectors  

Science.gov (United States)

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.

1980-01-01

219

Separating collectors for subsea blowouts  

Energy Technology Data Exchange (ETDEWEB)

A collector apparatus and method for use with a blown-out seabottom wellhead comprising a plurality of collector elements each having an extended, open base and an upper portion enclosing a volume to receive fluid comprising gas and lesser quantities of oil rising, in the water, from the wellhead, and risers connected to the collector elements and extending thereabove to conduct fluid therefrom. One collector element is disposed below at least one other collector element with an open volume defined therebetween, the first element positioned to intercept fluid rising from the wellhead, and the second element positioned to receive and collect excess flow of fluid that is not collected by the first element. A riser extends from the first collector element to the surface of the sea, and a second riser extends from the second collector element to a storage tank above the second collector element. The first riser includes an adjustable valve adapted to restrict flow through the riser whereby only a portion of gas from the blown-out wellhead is allowed to flow through the first riser and a further portion of gas and oil are rejected by the first collector element and flow into the second collector element, and the second riser is adapted to conduct gas in a gas-lift pumping flow rate capable of carrying water and accompanying oil from the second collector element to the storage tank.

Milgram, J.H.; Burgess, J.

1984-04-03

220

Optical, Energetic and Exergetic Analyses of Parabolic Trough Collectors  

Science.gov (United States)

Parabolic trough collectors generate thermal energy from solar energy. Especially, they are very convenient for applications in high temperature solar power systems. To determine the design parameters, parabolic trough collectors must be analysed with optical analysis. In addition, thermodynamics (energy and exergy) analysis in the development of an energy efficient system must be achieved. Solar radiation passes through Earth's atmosphere until it reaches on Earth's surface and is focused from the parabolic trough collector to the tube receiver with a transparent insulated envelope. All of them constitute a complex mechanism. We investigate the geometry of parabolic trough reflector and characteristics of solar radiation to the reflecting surface through Earth's atmosphere, and calculate the collecting total energy in the receiver. The parabolic trough collector, of which design parameters are given, is analysed in regard to the energy and exergy analysis considering the meteorological specification in May, June, July and August in Isparta/Turkey, and the results are presented.

Murat, Öztürk; Nalan Çiçek, Bezir; Nuri, Özek

2007-07-01

 
 
 
 
221

New performance testing stand for the characterization of innovative collectors and optical components; Neuer Leistungsteststand zur Charakterisierung innovativer Kollektoren und optischer Komponenten  

Energy Technology Data Exchange (ETDEWEB)

The variety of collector designs is on the increase. It is expected that technologies such as concentrating collectors, solar air collectors, heat pipe collectors and facade integrated collectors increase their market shares. In order to meet the various requirements for the measurement of this collector design, the Fraunhofer Institute for Solar Energy Systems (Freiburg, Federal Republic of Germany) and PSE-AG (Freiburg, Federal Republic of Germany) developed a new modular outdoor test stand was developed for performance testing. This test stand meets the highest requirements on tracking accuracy and flexibility. If necessary, mobile test equipment for testing of air temperature collectors and medium temperature collectors can be integrated easily.

Fahr, Sven; Schaefer, Arim; Mehnert, Stefan; Kramer, Korbinian; Hess, Stefan; Thoma, Christoph; Richter, Jens; Stryi-Hipp, Gerhard [Fraunhofer Institut fuer Solare Energiesysteme, Freiburg (Germany); Luginsland, Frank [PSE AG, Freiburg (Germany)

2010-07-01

222

Focusing solar collector  

Energy Technology Data Exchange (ETDEWEB)

A focusing solar collector is described which utilizes an elongated parabolic shaped mirror made from a sheet of drapable material so that when draped in a catenary like curved configuration, the sun's rays may be focused on a linear target which is axially aligned with the axis of the mirror. Means are provided for adjusting the angle of the drape of the catenary like curve in order to maintain the focus of the sun's rays on the linear target as the relative diurnal position of the sun to the collector changes. The optimum catenary like curve for the range of the drape angles involved is achieved by using a non-linear distribution of weight along the cross-section of the draped mirror material.

Kravitz, B.

1980-12-09

223

The weighted words collector  

CERN Document Server

Motivated by applications in bioinformatics, we consider the word collector problem, i.e. the expected number of calls to a random weighted generator of words of length $n$ before the full collection is obtained. The originality of this instance of the non-uniform coupon collector lies in the, potentially large, multiplicity of the words/coupons of a given probability/composition. We obtain a general theorem that gives an asymptotic equivalent for the expected waiting time of a general version of the Coupon Collector. This theorem is especially well-suited for classes of coupons featuring high multiplicities. Its application to a given language essentially necessitates some knowledge on the number of words of a given composition/probability. We illustrate the application of our theorem, in a step-by-step fashion, on three exemplary languages, revealing asymptotic regimes in $\\Theta(\\mu(n)\\cdot n)$ and $\\Theta(\\mu(n)\\cdot \\log n)$, where $\\mu(n)$ is the sum of weights over words of length $n$.

Boisberranger, Jérémie Du; Ponty, Yann

2012-01-01

224

Evacuated tubular or classical flat plate solar collectors?  

Directory of Open Access Journals (Sweden)

Full Text Available Evacuated tubular solar collectors are increasingly used all over the world due to their low coefficients of heat losses to the environment. They are presented as a device collecting much larger quantities of solar energy than is usually possible to obtain from typical flat collector. They have, however, unfavorable radiation transmissivity characteristics of transparent shield of absorber. It causes that the profits of energy gain at the operating conditions of typical solar system in our country only slightly dependent on the nature of the solar collectors applied. This article is an attempt to explain this phenomenon through theoretical considerations.

Zbyslaw Pluta

2011-01-01

225

Rewarming cardiac surgery patients: radiant heat versus forced warm air.  

Science.gov (United States)

This study compared time required to rewarm, incidence of shivering, and nurses' preferences in hypothermic postoperative cardiac surgery patients treated with a forced air warmer (Bair Hugger) or a noninfrared radiant heater (Thermal Ceiling). Data were collected on 38 subjects and 6 nonsubjects treated with warm blankets. Average minutes to rewarm were: forced air, 100.3; radiant heat, 99.3; and warm blankets, 188.2. The warm air subjects had significantly higher skin temperatures, lower incidence of shivering, and less severe afterdrop, suggesting that rewarming in these patients resulted from heat gained from the environment. Nurses preferred the forced air warmer to the noninfrared radiant heater. PMID:8183660

Giuffre, M; Heidenreich, T; Pruitt, L

1994-01-01

226

The radiant of the Leonids meteor storm in 2001  

CERN Document Server

We have measured the radiant of the Leonids meteor storm in November 2001 by using new observational and analysis techniques. The radiant was measured as the intersections of lines which were detected and extrapolated from images obtained at a single observing site (Akeno Observatory, Japan). The images were obtained by two sets of telephoto lenses equipped with cooled CCD cameras. The measured radiant, (R.A., Dec.)=(154$^\\circ$.35, 21$^\\circ$.55) (J2000), is found to be in reasonable agreement with the theoretical prediction by McNaught and Asher (2001), which verifies their dust trail theory.

Torii, K; Yanagisawa, T; Ohnishi, K; Torii, Ken'ichi; Kohama, Mitsuhiro; Yanagisawa, Toshifumi; Ohnishi, Kouji

2002-01-01

227

RANBO: An N-Body Simulator for Radiant Determination  

Science.gov (United States)

We present the RAdiant N-Body Orbit (RANBO) tool for the determination of the pre-atmospheric orbital parameters of meteors. RANBO uses an N-Body Runge Kutta integrator to determine the true radiant of the meteor. The motivation for the development of RANBO was the lack of agreement between other methods of radiant determination such as the 'standard' zenithal attraction method (Gural, 2001) or the 'Gravitational Sphere of Influence' method (Diaz del Rio & Koschny, 2004). The software has been designed to interface with the Virtual Meteor Observatory, but also to function as a stand-alone tool. The architecture of the software is presented as well as initial comparative results.

Marin-Yaseli de la Parra, J.

2011-01-01

228

Hybrid thermoelectric solar collector design and analysis  

Energy Technology Data Exchange (ETDEWEB)

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/coldjunction 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.

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

1982-11-01

229

Hybrid thermoelectric solar collector design and analysis  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1982-11-01

230

Hybrid thermoelectric solar collector design and analysis  

Science.gov (United States)

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.

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

1982-01-01

231

The flat solar collector an approach to its evaluation  

International Nuclear Information System (INIS)

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

1977-01-01

232

Energy-Efficient Sol-Gel Process for Production of Nanocomposite Absorber Coatings for Tubular Solar Thermal Collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The energy efficiency of production processes for components of solar energy systems is an important issue. Other factors which are important for the production of products such as black selective solar coatings include production speed, cycle time and homogeneity of the coating, as well as the minimization of the quantity of the needed chemical precursors. In this paper a new energy efficient production process is presented for production of optically selective coatings for solar thermal abs...

Scartezzini, Jean-louis; Joly, Martin; Antonetti, Yann; Python, Martin; Gonzalez, Marina; Gascou, Thomas; Hessler, Ai?cha; Schueler, Andreas

2013-01-01

233

Simple process heat collector system  

Energy Technology Data Exchange (ETDEWEB)

The direct boiling of a process fluid in a concentrating solar collector can have advantages over a conventional system using pumped oil and a heat exchanger. This paper describes such a 'boiling in the collector' (BIC) system and the test results from operating a prototype system at 350 F(177 C) using R-113, a refrigerant. These tests demonstrated the feasibility of the BIC system but the overall collector efficiency was less than expected.

Batton, W.D.; Barber, R.E.

1980-08-01

234

A solar collector design procedure for crop drying  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A design procedure was proposed for sizing solar-assisted crop-drying systems and assessing the combination of solar collector area and auxiliary energy needs that meets the requirements of the load. Two empirical correlations were compared for use with high thermal inertia solar collectors that are cheap and appropriate for rural areas. A case study as performed in the city of Campinas in southeastern Brazil. Grain drying with partial air heating by solar energy can provide an annual savings...

2005-01-01

235

Parabolic trough collectors for industrial and commercial applications  

Energy Technology Data Exchange (ETDEWEB)

Industrial Solar Technology Corporation (IST) manufactures and installs parabolic trough solar energy systems for large-scale commercial and industrial applications. Parabolic trough collectors have advanced significantly over the last fifteen years and are the most developed and widely deployed type of solar concentrator. Collector efficiency has increased, installed costs have decreased, and system reliability has improved. These positive trends have moved parabolic trough technology to commercial viability in niche markets where energy costs are high and sunlight is abundant.

Gee, R.C.

1997-06-01

236

Characterization of flat-plate air solar collectors  

Energy Technology Data Exchange (ETDEWEB)

The main characterization parameters are presented, and, a simple and rigorous, reduced energy characterization is defined. Models used for the resolution of equations where solutions are analytical functions are developed. The results of experimental tests on collectors complying with the calculation productions are analyzed. The applicability of the reduced energy characterization is studied. The thermal exchange with the air heat conductors which allows interesting collector to be suggested is studied.

Rampazzo, D.

1982-10-01

237

Concentrating solar collector - final design  

Science.gov (United States)

Final report of program to improve commercially available concentrating solar collector describes final hardware, discusses problems encountered, and presents certification statements, photographs, and recommendations for modification.

Parker, J. C.

1980-01-01

238

21 CFR 880.5130 - Infant radiant warmer.  

Science.gov (United States)

...Classification. Class II (Special Controls): (1) The Association for the Advancement of Medical Instrumentation (AAMI) Voluntary Standard for the Infant Radiant Warmer; (2) A prescription statement in accordance with § 801.109 of...

2010-04-01

239

Experimental Analysis of Radiant Ceiling Systems Coupled to its Environment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents the results of an experimental analysis of the radiant ceiling systems in both heating and cooling modes coupled to its environment (fenestration, walls, internal loads and ventilation system). The main objective of this study is to present the results of the systems performance and measurement methods used to evaluate the influence of some important parameters on the radiant ceiling capacity and comfort conditions. Two test chambers are adapted in a way to reproduce as...

Fonseca, Ne?stor; Cuevas, Cristian; Lemort, Vincent

2010-01-01

240

Semen quality in welders exposed to radiant heat.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Several studies suggest that welding is detrimental to the male reproductive system. Welding fume and radiant heat are of interest as possible causal factors. This study investigates semen quality and sex hormone concentrations among 17 manual metal arc alloyed steel welders with a moderate exposure to radiant heat (globe temperature ranging from 31.1 degrees to 44.8 degrees C), but without substantial exposure to welding fume toxicants. During exposure to heat the skin temperature in the gro...

Bonde, J. P.

1992-01-01

 
 
 
 
241

Measurement of night sky emissivity in determining radiant cooling from cool storage roofs and roof ponds  

Energy Technology Data Exchange (ETDEWEB)

Members of the Passive Solar Research Group have undertaken a project to measure the radiant cooling component of a cool storage roof at the Solar energy Research Test Facility located at Allwine Prairie near Bennington, Nebraska. There are over fourteen hundred data points taken in a year`s period of time that measure sky and surface water temperatures, night sky radiation, ambient temperature and dew point temperature. The purpose of this study is to develop a relationship between night sky emissivity values and dew point temperatures in order to develop an algorithm to predict radiant cooling. The equation developed at the University of Nebraska is: e{sub sky} = 0.736 + 0.00577 {times} T{sub dp} where: e{sub sky} is the sky emissivity (0

Chen, B.; Clark, D.; Maloney, J.; Mei, W.N.; Kasher, J. [Univ. of Nebraska, Omaha, NE (United States)

1995-11-01

242

Radiant heat transfer of optically thick spherical shells through a layer of hot almost transparent plasma  

International Nuclear Information System (INIS)

A model of radiant heat exchange in a multilayer system comprising optically thick spherical shells with intermediate layers of high-temperature (hot) plasma is developed for effective solution of spherically-symmetric one-dimensional problems of radiation gasodynamics with simultaneous existence of optically thin and optically thick layers of substance. Radiation transport in optically thick layers in the suggested model is described in the known approximation of radiant thermal conductivity, but in this case integral boundary conditions including radiation effects of the given layer by volumetric radiation of optically thin plasma and weak radiation of the neighbouring optically thick layer (and self-radiation) are derived for equations of thermal conductivity. The effect of substance local heating by surface radiation of surrounding optically thick layers at the expense of partial absorption of this radiation by plasma is investigated in hot plasma. The equations of the model comply with the laws of energy conservation and they correspond to Kirchhoff law

1987-01-01

243

Radiant heat testing of the H1224A shipping/storage container  

Energy Technology Data Exchange (ETDEWEB)

H1224A weapons containers have been used for years by the Departments of Energy and Defense to transport and store W78 warhead midsections. Although designed to protect the midsections only from low-energy impacts, a recent transportation risk assessment effort has identified a need to evaluate the container`s ability to protect weapons in more severe accident environments. Four radiant heat tests were performed: two each on an H1224A container (with a Mk12a Mod 6c mass mock-up midsection inside) and two on a low-cost simulated H1224A container (with a hollow Mk12 aeroshell midsections inside). For each unit tested, temperatures were recorded at numerous points throughout the container and midsection during a 4-hour 121{degrees}C (250{degrees}F) and 30-minute 1010{degrees}C (1850{degrees}F) radiant environment. Measured peak temperatures experienced by the inner walls of the midsections as a result of exposure to the high-temperature radiant environment ranged from 650{degrees} C to 980{degrees} C (1200{degrees} F to 1800{degrees}F) for the H1224A container and 770 {degrees} to 990 {degrees}C (1420{degrees} F to 1810{degrees}F) for the simulated container. The majority of both containers were completely destroyed during the high-temperature test. Temperature profiles will be used to benchmark analytical models and predict warhead midsection temperatures over a wide range of the thermal accident conditions.

Harding, D.C.; Bobbe, J.G.; Stenberg, D.R.; Arviso, M.

1994-05-01

244

Super-radiant scattering of dispersive fields  

International Nuclear Information System (INIS)

Motivated by analogue models of classical and quantum field theory in curved spacetimes and their recent experimental realizations, we consider wave scattering processes of dispersive fields exhibiting two extra scattering channels. In particular, we investigate how standard super-radiant scattering processes are affected by subluminal or superluminal modifications of the dispersion relation. We analyse simple (1+1)-dimensional toy models based on fourth-order corrections to the standard second-order wave equation and show that low-frequency waves impinging on generic scattering potentials can be amplified during the process. In specific cases, by assuming a simple step potential, we determine quantitatively the deviations in the amplification spectrum that arise due to dispersion, and demonstrate that the amplification can be further enhanced due to the presence of extra scattering channels. We also consider dispersive scattering processes in which the medium where the scattering takes place is moving with respect to the observer and show that super-radiance can also be manifest in such situations. (paper)

2013-04-21

245

Radiant-Heat Spray Calcination Studies  

International Nuclear Information System (INIS)

The radiant-heat spray calcination process for conversion of liquid wastes to solids is described and the design of a one-gallon-per-hour spray calcination unit coupled with a small melt pot, capable of being run separately as a pot calciner, is discussed. The units were designed to test the feasibility of the calcination process with actual Purex plant waste in terms of the process as a unit operation, off-gas treatment, fission-product behaviour, condensate and calcined waste characteristics. The entire system was made to fit into an available 7-1/2 ft x 15 ft x 15 ft tall, manipulator-equipped, shielded cell which is also described. Included in the design discussion are: the resistance heating of the spray calciner column, thermal insulation of the column, spray nozzle, method of nozzle replacement, induction heating of the melt pot, radioactivity scanner for the pot, off-gas processing system including condenser, scrubber and filters, off-gas sampling device, liquid sampling device, wash-down system, feed system, instrumentation and control methods. The experience gained in operating the calciners and associated equipment is discussed. Experimental results presented show the effectiveness of off-gas decontamination and behaviour of gross chemical constituents and some specific fission products. (author)

1963-02-01

246

Jet pulse bag type collector  

Energy Technology Data Exchange (ETDEWEB)

A jet pulse bag type collector is described which makes use of a venturi and a wire cage which extends internally substantially throughout the length of the filter bag, in which the wire cage is supported from the venturi and the filter bag is supported between the wire cage and a portion depending from about the opening through the tube sheet of the collector.

Evenstad, D.C.

1981-02-17

247

Method and apparatus for collecting, intensifying and storing solar energy  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus for collecting, intensifying and storing solar energy which includes a hollow spherical vessel having a polished reflective interior surface are described. A window is provided in the wall of the vessel for allowing concentrated rays from the sun to enter into the interior of the vessel and be absorbed by a solar collector. The collector includes a substantially black (Or a selective coating) heat absorbing surface carried by a spherical member which is centrally located within the spherical vessel. Heat absorbing media such as metal shots, are carried within the spherical member and change from a solid state to a liquid state as it absorbs the solar energy. The heat absorbing media cause radiant energy to be radiated radially in a symmetric beam pattern to the reflective vessel wall where the radiation is reflected back to the spherical member. The reflected radiant energy in conjunction with the sun's rays intensify the temperature of the heat absorbing media producing a thermal power supply.

Nilsson, J.E.

1981-07-28

248

Apparatus for collecting, intensifying and storing solar energy  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus for collecting, intensifying and storing solar energy which includes a hollow spherical vessel 10 having a polished reflective interior surface. A window 32 is provided in the wall of the vessel for allowing concentrated rays from the sun to enter into the interior of the vessel and be absorbed by a solar collector 20. The collector includes a substantially black (or a selective coating) heat absorbing surface carried by a spherical member 16 which is centrally located within the spherical vessel. Heat absorbing media 18 such as metal shots are carried within the spherical member and change from a solid state to a liquid state as it absorbs the solar energy. The heat absorbing media 18 cause radiant energy to be radiated radially in a symmetric beam pattern to the reflective vessel wall where the radiation is reflected back to the spherical member 16. The reflected radiant energy, in conjunction with the sun's rays, intensify the temperature of the heat absorbing media, producing a thermal power supply.

Nilsson, J.E. Sr.

1984-05-22

249

A detailed thermal model of a parabolic trough collector receiver  

International Nuclear Information System (INIS)

Parabolic trough collectors are made by bending a sheet of reflective material into a parabolic shape. A metal black pipe, covered with a glass tube to reduce heat losses, is placed along the focal line of the collector. The concentrated radiation reaching the receiver tube heats the fluid that circulates through it, thus transforming the solar radiation into useful heat. It is sufficient to use a single axis tracking of the sun and thus long collector modules are produced. In this paper a detailed thermal model of a parabolic trough collector is presented. The thermal analysis of the collector receiver takes into consideration all modes of heat transfer; convection into the receiver pipe, in the annulus between the receiver and the glass cover, and from the glass cover to ambient air; conduction through the metal receiver pipe and glass cover walls; and radiation from the metal receiver pipe and glass cover surfaces to the glass cover and the sky respectively. The model is written in the Engineering Equation Solver (EES) and is validated with known performance of existing collectors and subsequently is used to perform an analysis of the collector we are going to install at Archimedes Solar Energy Laboratory at the Cyprus University of Technology.

2012-12-01

250

Life cycle assessment on solar collectors  

International Nuclear Information System (INIS)

A Life Cycle Assessment (LCA) is a tool for analysing and estimating the total influence on the environment during the complete life cycle of a certain product. The assessment can bring valuable information about the production processes, the use of materials, the use and the disposal of the product. This information can be used to determine, how to improve the product environmentally. The LCA information can also be used as a comparative study to determine which of two products are environmentally preferably. LCA''s on solar collectors are interesting because solar energy systems are introduced to encourage a sustainable development, hence it follows that the systems themselves should be based on a sustainable technology. The collector should produce as much energy as possible during its lifetime, but it is also important that it is produced in an environmentally friendly way, that it can be disposed properly after use and so on. (orig.) 2 refs

1997-06-09

251

Thermal Evaluation of a Solarus PV-T collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Low concentrator PV-T hybrid systems produce both electricity and thermal energy; this fact increases the overall efficiency of the system and reduces the cost of solar electricity. These systems use concentrators which are optical devices that concentrate sunlight on to solar cells and reduce expensive solar cell area. This thesis work deals with the thermal evaluation of a PV-T collector from Solarus.Firstly the thermal efficiency of the low concentrator collector was characterized for the ...

2013-01-01

252

Design Support System for Parabolic Trough Solar Collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Parabolic Trough Collector (PTC) is special kind of heat exchanger that is able to transfer solar radiation energy to fluid medium that flow through it. Designing a PTC for a specific working condition requires determination of several parameters and referring to a number of design standards and handbooks. Hence, a design support system is required to determine the necessary parameters and simulate different working conditions. Although, a number of design support systems for solar collectors...

Woldemichael, Dereje E.; Cheng, Hoe K.; Woldeyohannes, Abraham D.; Lim Chye Ing

2012-01-01

253

Radiant heat exchange of optically thick spherical envelopes through a layer of hot almost transparent plasma  

International Nuclear Information System (INIS)

A model of radiant heat exchange in a multilayer system is developed to effectively solve sherically symmetric one-dimensional problems of the radiation gas dynamics with simultaneously present optically thin and thick substance layers. This multilayer system consists of optically thick spherical envolopes with intermediate layers of high-temperature (hot) plasma. In the proposed model the radiation transfer in optically thick layers is described in the framework of a known approximation of radiant thermal conductivity, but for the thermal conductivity equations the integral boundary conditions are deduced which include effects of irradiation of this layer by three-dimensional radiation of an optically thin plasma and by attenuated radiation of a neighbouring optically thick layer (and by self-radiation). Effect of local radiant heating of substance by the surrounding optically thick layers at the expense of partial absorption of radiation by a plasma is simulated for a hot plasma. The model equations satisfy the laws of energy conservation and correspond to the Kirchhoff law. A high-temperature plasma substance is considered to be fully ionized so that only slowing down absorption and phonon radiation occur in it. Derivations of averaged radiation absorption factors and corresponding plasma emissivities are presented

1983-01-01

254

Microenvironmental changes and plant responses due to shading and wind deflectio by solar collectors: a simulation study  

Energy Technology Data Exchange (ETDEWEB)

The potential microenvironmental changes at the ground surface beneath arrays of solar mirrors or collectors were investigated in a Sonoran Desert ecosystem, utilizing a simulated array of plywood panels. The simulated array consisted of twelve panels designed to exhibit a similar shape, tilt, and spacing as is expected to occur in heliostat fields of solar thermal facilities or in arrays of photovoltaic collectors. The experimental design in the study was based on comparing two microsites in the simulated array versus the open desert. Presence of the panels results in up to a 90% reduction in solar radiance during the midday period, with microsites beneath each panel receiving about 14% of the open desert irradiance over the whole day. The array of panels also effected a 14% to 60% reduction in monthly accumulated wind flow in the center of the array. The combination of reduced radiant energy input and wind deflection resulted in significantly reduced surface and soil temperatures in the heavily shaded sites, and moderately reduced surface and soil temperatures in the sunny microsites. Plant responses to a cooler, moister environment were: (1) higher diversity and survival of winter spring annuals; (2) proliferation of C/sub 3/ annuals in the summer flora versus the more typical C/sub 4/ annuals in the open; (3) greater new shoot production of shrubs; (4) greater gross photosynthesis and stomatal conductance of the two shrub species in the warm dry season, but not in the cool wet season; (5) increased leaf retention and reduction in the typical leaf polymorphic character into the dry season of the drought deciduous Ambrosia deltoidea; and, (6) invasion of the heavily shaded areas of the array by a pseudo-riparian species, Baccharis sarothroides. (WHK)

Patten, D.T.; Smith, S.D.

1980-11-01

255

LHCb Tag Collector  

Science.gov (United States)

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

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

2011-12-01

256

Studies of collectors, 9  

International Nuclear Information System (INIS)

Chelating surfactants bearing hydroxyaminocarbonyl and amino groups (RnAHx) and cotelomer-type surfactants bearing hydroxyaminocarbonyl and pyridyl groups (Ls-VP-Q-Hx) were prepared and applied as flotation collectors for a trace amount of uranium. The uranium in an aqueous solution of pH 4 - 8 and in seawater was floated more effectively by ion flotation using RnAHx or by foam fractionation using Ls-VP-Q-Hx, compared with alkylhydroxamic acid (RnHx) and telomers bearing hydroxyaminocarbonyl groups (Lo-Hx). The effective flotation was concluded to be due to the chelate effects between the two groups on the complex formation and to the HLB of the resulting complex. Furthermore, the uranium recoveries were examined by using a hydroxamic acid polymer (62Hx), a N-methylhydroxamic acid telomer (Ls5.6MHx), and its cotelomer (Ls3.2VP4.5MHx). (author)

1987-01-01

257

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System  

Energy Technology Data Exchange (ETDEWEB)

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.

Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

1998-01-16

258

Thermal Efficiency of Double Pass Solar Collector with Longitudinal Fins Absorbers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Problem statement: One of the most important components of a solar energy system is the solar collector. The performances of double-pass solar collector with longitudinal fins absorbers are analyzed. Approach: The study involves a theoretical study to investigate the effect of mass flow rate, number and height of fins on efficiency, which involves steady-state energy balance equations on the longitudinal fins absorber of solar collectors. The theoretical solu...

2011-01-01

259

Comparative Study on Solar Collector’s Configuration for an Ejector-Refrigeration Cycle  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Solar collector’s configuration plays important role on solar-powered refrigeration systems to work as heat source for generator. Three types of solar collector consisting of flat plate, evacuated tube, and compound parabolic solar collectors are compared to investigate their performances. The performances consist of the behavior of heat which can be absorbed by the collectors, heat loss from the collectors and outlet temperature of working fluid at several slopes of the solar collectors. T...

2008-01-01

260

Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer  

CERN Document Server

The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to th...

Rabus, H; Scholze, F; Thornagel, R; Ulm, G

2002-01-01

 
 
 
 
261

Comfort due to radiant surfaces at building facades. Behaglichkeit durch Strahlungsflaechen an Gebaeudefassaden  

Energy Technology Data Exchange (ETDEWEB)

The opening of building facades, i.e. the use of transparent elements results in enormous thermal loads for the building. Radiant gain in summer is a minor problem which can easily be solved with shading systems. But the problem of radiant losses in winter is often neglected. Comfort near glazed areas can be improved by providing radiant surfaces for the compensation of the cold glazed areas. In this article a mathematical description of radiant temperature referred to half-space is given with which the arrangement of the radiant surfaces can be determined. In summer these radiant surfaces filled with cooling water are used to compensate for the warm glazings. (BWI)

Reichel, W. (Ingenieurbuero Timmer Reichel GmbH, Haan (Germany))

1994-02-01

262

Thermal Performance of an Annealed Pyrolytic Graphite Solar Collector  

Science.gov (United States)

A solar collector having the combined properties of high solar absorptance, low infrared emittance, and high thermal conductivity is needed for applications where solar energy is to be absorbed and transported for use in minisatellites. Such a solar collector may be used with a low temperature differential heat engine to provide power or with a thermal bus for thermal switching applications. One concept being considered for the solar collector is an Al2O3 cermet coating applied to a thermal conductivity enhanced polished aluminum substrate. The cermet coating provides high solar absorptance and the polished aluminum provides low infrared emittance. Annealed pyrolytic graphite embedded in the aluminum substrate provides enhanced thermal conductivity. The as-measured thermal performance of an annealed pyrolytic graphite thermal conductivity enhanced polished aluminum solar collector, coated with a cermet coating, will be presented.

Jaworske, Donald A.; Hornacek, Jennifer

2002-01-01

263

Solar sorption refrigerator using a CPC collector  

Energy Technology Data Exchange (ETDEWEB)

A prototype Compound Parabolic Concentrating (CPC) solar energy collector for a sorption refrigerator is presented. It consists of two CPC reflectors, two absorbers and a single glazing cover. The absorber is made with seamless steel tube covered in a selective surface (absorptance: 0.95) and contains aluminium fins, activated carbon and ammonia. The parabolas are manufactured from aluminium foil and a reflective microfilm is bonded on its surfaces to provide high solar reflectance (0.95). The concentration ratio of the collector is about 2.4 and corresponds to an incidence half angle of 25deg. A numerical model of the absorber is described. Simulations with a daily solar radiation corresponding to tropical areas are presented. (Author)

Tamainot-Telto, Z.; Critoph, R.E. [Warwick Univ., Engineering Dept., Coventry (United Kingdom)

1999-01-01

264

Accelerated Testing of Solar Collector Durability  

DEFF Research Database (Denmark)

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.

Svendsen, Sv Aa Højgaard

1996-01-01

265

Convective and radiative heat transfer in MHD radiant boilers  

International Nuclear Information System (INIS)

A combined convection-gas radiation, two-zone flow model is formulated for study of the heat transfer characteristics of MHD radiant boilers. The radiative contributions of carbon dioxide, water vapor, potassium atoms, and slag particles are included in the formulation, and are determined by solving the radiation transport equation using the P1 approximation. The scattering and absorption cross section of slag particles are calculated from Mie theory. The model is used to analyze the scale-up of heat transfer in radiant boilers with refractory thickness, wall emissivity, and boiler size, under conditions of a gas composition and slag particle spectrum typical of coal-fired MHD combustion. A design procedure is suggested for sizing radiant boilers so as to achieve required heat extraction rate and to provide a flow residence time that is adequate for decomposition of NO/sub x/ to acceptable levels

1981-01-01

266

Design package for concentrating solar collector panels  

Energy Technology Data Exchange (ETDEWEB)

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

1978-08-01

267

Development of economic collector systems  

Energy Technology Data Exchange (ETDEWEB)

A comparison of systems of the different modular concepts was introduced for collector development work. The HELIOMAN-3-32/A collector module was used as the basis of comparison. Because of the results of this comparison, the single axis/horizontal north-south variant was given preference for development work. Activities for the design and development of the following components for the single axis horizontal trough following the sun took place: Parabolic mirror (1.5 m long, 1.1 m wide, thickness of glass 5 mm), absorber (38 mm diameter), trough structure (combination of several rows of mirrors), trough drive with 4 joint drive. Apart from this development work for a cylindrical paraboloid collector, the complete unit of a collector area was also considered (reducing the price).

Kraft, M.

1983-01-01

268

New concepts for solar collectors in 2030  

Energy Technology Data Exchange (ETDEWEB)

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.

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

269

Design package for concentrating solar collector panels  

Science.gov (United States)

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.

1978-01-01

270

Numerical and experimental investigation of a single ended radiant tube  

Energy Technology Data Exchange (ETDEWEB)

The Single Ended Radiant (SER) tube is an advanced type of the Natural-Gas Fired Radiant (NGFR) tubes which have been widely used in industrial heating processes. The present paper deals with the experimental investigations and numerical simulations of the SER tube with the objective of validating the turbulence models to which the final solutions have been found very sensitive. A RNG-based turbulence model is firstly validated against measurements in relaminarization, chemical reacting flows and then is applied to model the SER tube case. The performance of this RNG model is discussed and the agreement between the predictions and the measurements has been found satisfactory.

Mei, F.; Meunier, H.

1997-07-01

271

Exergy Efficiency Analysis of Embedded Pipe in Radiant Ceiling Cooling System  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this study is to investigate an exergy analysis on embedded pipes of radiant ceiling cooling system. Based on the thermodynamic principles, the exergy analysis model of radiant ceiling cooling system is established. The exergy efficiency of radiant ceiling cooling system and its main equipments can be simulated and calculated by the model. Under the different pipe spacing, depth and diameter, the exergy efficiency of radiant ceiling, refrigerating unit, pump and radiant ceiling cooling system and the surface temperature of radiant ceiling panel are compared and analyzed and the exergy loss coefficients of radiant ceiling panel, refrigerating unit and pump are calculated. The conclusions show that pipe depth and spacing have primary influence on exergy efficiency and surface temperature distribution respectively and the refrigerating unit is the most important part for exergy saving in radiant ceiling cooling system.

Qingyun Shou

2013-04-01

272

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

Directory of Open Access Journals (Sweden)

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

Lívia Bodonská

2006-09-01

273

Thin film absorber for a solar collector  

Science.gov (United States)

This invention pertains to energy absorbers for solar collectors, and more particularly to high performance thin film absorbers. The solar collectors comprising the absorber of this invention overcome several problems seen in current systems, such as excessive hardware, high cost and unreliability. In the preferred form, the apparatus features a substantially rigid planar frame with a thin film window bonded to one planar side of the frame. An absorber in accordance with the present invention is comprised of two thin film layers that are sealed perimetrically. In a preferred embodiment, thin film layers are formed from a metal/plastic laminate. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. The absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

Wilhelm, William G. (Cutchogue, NY)

1985-01-01

274

Improved Collectors for High Power Gyrotrons  

International Nuclear Information System (INIS)

High power gyrotrons are used for electron cyclotron heating, current drive and parasitic mode suppression in tokamaks for fusion energy research. These devices are crucial for successful operation of many research programs around the world, including the ITER program currently being constructed in France. Recent gyrotron failures resulted from cyclic fatigue of the copper material used to fabricated the collectors. The techniques used to collect the spent beam power is common in many gyrotrons produced around the world. There is serious concern that these tubes may also be at risk from cyclic fatigue. This program addresses the cause of the collector failure. The Phase I program successfully demonstrated feasibility of a mode of operation that eliminates the cyclic operation that caused the failure. It also demonstrated that new material can provide increased lifetime under cyclic operation that could increase the lifetime by more than on order of magnitude. The Phase II program will complete that research and develop a collector that eliminates the fatigue failures. Such a design would find application around the world.

2009-01-01

275

Impact of different internal convection control strategies in a non-evacuated CPC collector performance  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Over the last decade the technological advances observed in solar collector materials, namely better spectrally selective absorber coatings and ultra clear glass covers, contribute to performance improvements and translate into higher operational temperature ranges with higher efficiency values. While the use of Evacuated Tube Collectors (ETCs) is becoming widespread in the thermal conversion of solar energy, non-evacuated solar collectors still hold advantages at manufacturing, reliability a...

2012-01-01

276

Shape Control of Solar Collectors Using Shape Memory Alloy Actuators  

Science.gov (United States)

Solar collectors that are focused on a central receiver are designed with a mechanism for defocusing the collector or disabling it by turning it out of the path of the sun's rays. This is required to avoid damaging the receiver during periods of inoperability. In either of these two cases a fail-safe operation is very desirable where during power outages the collector passively goes to its defocused or deactivated state. This paper is principally concerned with focusing and defocusing the collector in a fail-safe manner using shape memory alloy actuators. Shape memory alloys are well suited to this application in that once calibrated the actuators can be operated in an on/off mode using a minimal amount of electric power. Also, in contrast to other smart materials that were investigated for this application, shape memory alloys are capable of providing enough stroke at the appropriate force levels to focus the collector. Design and analysis details presented, along with comparisons to test data taken from an actual prototype, demonstrate that the collector can be repeatedly focused and defocused within accuracies required by typical solar energy systems. In this paper the design, analysis and testing of a solar collector which is deformed into its desired shape by shape memory alloy actuators is presented. Computations indicate collector shapes much closer to spherical and with smaller focal lengths can be achieved by moving the actuators inward to a radius of approximately 6 inches. This would require actuators with considerably more stroke and some alternate SMA actuators are currently under consideration. Whatever SMA actuator is finally chosen for this application, repeatability and fatigue tests will be required to investigate the long term performance of the actuator.

Lobitz, D. W.; Grossman, J. W.; Allen, J. J.; Rice, T. M.; Liang, C.; Davidson, F. M.

1996-01-01

277

Combined solar collector and storage systems  

International Nuclear Information System (INIS)

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

2000-10-19

278

Operating principle of innovative recuperative radiant tubes under actual operating conditions  

Energy Technology Data Exchange (ETDEWEB)

A newly developed recuperative radiant tube was tested under actual operating conditions. The author presents the findings of these tests describing the heat flows and heat transfer in the radiant tube and recuperator burner and showing the influence exerted by the arrangement in the furnace on the radiant tube.

Pfau, H.

1983-10-01

279

Quantum Phase Transition in Ultracold 87Rb Atom Gas with Radiant Field  

CERN Multimedia

A second-order quantum phase transition in two-species Bose-Einstein condensates of 87Rb atoms coupled by a quantized radiant field is revealed explicitly in terms of the energy spectrum which is obtained in the thermodynamic limit and is controllable by the coupling parameter between the atom and field. The scaling behavior of the collective excitation modes at the critical transition point is seen to be in the same universality class as that of the Dicke model. It is also demonstrated that the quantum phase transition is realizable below the critical temperature of BEC and can be detected experimentally by measuring the abrupt change of atom population imbalance.

Chen, G; Liu, W M; Chen, Gang

2006-01-01

280

Predictions of the meteor radiant point associated with a comet  

International Nuclear Information System (INIS)

Under the condition of equal heliocentric distances on the ecliptic plane, predictions of cometary meteor orbit and its radiant point are presented and discussed in terms of meteor observations. Some adjustment methods regarding the parent cometary orbit in order to fulfill the proposed conditions for the apparition of meteor streams are also presented. (author)

1990-01-01

 
 
 
 
281

Predictions of the meteor radiant point associated with a comet  

Energy Technology Data Exchange (ETDEWEB)

Under the condition of equal heliocentric distances on the ecliptic plane, predictions of cometary meteor orbit and its radiant point are presented and discussed in terms of meteor observations. Some adjustment methods regarding the parent cometary orbit in order to fulfill the proposed conditions for the apparition of meteor streams are also presented. (author).

Hasegawa, Ichiro (Otemae Junior College, Hyogo (Japan))

1990-01-01

282

Experimental and analytical study of a boiling collector in thermal siphon operation  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to analytically and experimentally evaluate the performance of a boiling solar collector in thermal siphon operation so that, in future work, solar collectors can be optimized for boiling operation. A new procedure, based on boiling heat transfer fundamentals, is developed to estimate the rate of energy gain in the collector. The temperature of the absorber plate is determined from the simultaneous solution of the rate of energy absorbed by the collector and the rate of energy used in boiling as a function of vapor bubble density, the energy required for bubble formation, and the volumetric flow rate through the collector. Since the volumetric flow rate could not be predicted theoretically, experimentally estimated values are used in the numerical calculation. This model is an improvement over previous models which assume that the total mass flow rate that flows through the collector boils, when in reality just a small percent of this mass flow boils and most of it is recirculated. To validate the analytical model, the thermal efficiency and the absorber plate temperature of two collector-condenser systems are experimentally determined. Measurements with both a conventional sheet with tube and a waffled flat plate collector indicate the importance of collector geometry. The two-phase thermal siphon system operates at practically the same thermal efficiency as the hydronic single-phase system, but it uses one less pump, the net rate of useful energy transfer in the two-phase system is higher than in the single-phase system. When boiling collectors are designed for two-phase operation, they may out-perform hydronic collectors.

Silva, M. da; Eugenia, M.

1992-01-01

283

Performances of Low Temperature Radiant Heating Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Low temperature heating panel systems offer distinctive advantages in terms of thermal comfort and energy consumption, allowing work with low exergy sources. The purpose of this paper is to compare floor, wall, ceiling, and floor-ceiling panel heating systems in terms of energy, exergy and CO2 emissions. Simulation results for each of the analyzed panel system are given by its energy (the consumption of gas for heating, electricity for pumps and primary energy) and exergy consumption, the pri...

Bojic?, Milorad; Cvetkovic, Dragan; Skerlic?, Jasmina; Nikolic?, Danijela; Boyer, Harry

2012-01-01

284

Orientation of stationary axial collectors  

Energy Technology Data Exchange (ETDEWEB)

Attention is drawn to the fact that stationary solar collectors with axial symmetry have a third degree of freedom which must be considered, in addition to their azimuth and tilt angles, if their orientation is to be optimized on an annual or seasonal basis. The authors set up the equations needed to describe collector orientation in terms of all angles, including this extra degree of freedom which they refer to as skewness. Examples of the use of these equations are then given, both for northern and southern latitudes, which illustrate the manner in which skewness may be taken into consideration and highlight the importance of doing this. For the sake of simplicity the illustrative examples treat only the direct beam component of the total insolation intercepted by the collector.

Faiman, D.; Mills, D.R. (Sydney Univ., New South Wales (Australia))

1992-10-01

285

Process heat generation in industrial buildings using solar concentration collectors  

International Nuclear Information System (INIS)

One of the most promising and important applications of solar energy is in the area of process heat generation for industry. While the greater part of the effort in solar research has traditionally been spent on developing devices for domestic use, it has long been recognized that the industrial user has a far greater potential. Apart from the quantities of energy involved, the industrial user is a convenient one and particularly geared for solar energy utilization. The main limitation of the industrial user with regard to solar energy utilization is his need for steam - rather than hot water at temperatures below 100 degrees C. The common flat-plate collectors are inadequate for generating steam and other types of collectors, usually more expensive, have to be employed. This paper describes a study aimed at incorporating a solar collector of a particular design in the roof structure of an industrial building, thereby bringing down the cost. The particular feature of the collector, based on the SRTA Stationary Reflector/Tracking Absorber concept, is a stationary spherical mirror which focuses the solar rays on a small, cylinder-shaped tracking absorber. Industrial roofs are usually constructed of modular elements, mounted on a support structure. It has been suggested to combine the spherical mirror of the collector in the modular roof element, thus obtaining a roof which can serve at the same time as a solar collector. The advantages to doing this are many: The added cost of the solar system is reduced since the roof itself provides the structure of its mirrors; the mirrors reduce the insulation requirements of the roof; optimum utilization of the roof area for solar energy collection can be achieved; the mirror surface can be renewed and refurbished in-situ, and there is no need to replace the entire mirror when its reflectivity decreases in time. (author)

1994-04-25

286

Solar collector method and apparatus  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a solar collector system. It comprises: an extruded solar collector with a plurality of orifices longitudinally extending therethrough; an input manifold having a central conduit member with male and female ends and a plurality of radially extending nipples corresponding to the plurality of orifices; an output manifold having a central conduit member with male and female ends and a plurality of radially extending nipples corresponding to the plurality of orifices; means for positioning the nipples of the input manifold into one end of the plurality of orifices and for positioning the nipples of the output manifold into the other end of the plurality of orifices such that a fluid flowing into the input manifold flows through the nipples of the input manifold into the plurality of orifices and then through the nipples of the output manifold into the output manifold; a sheet of transparent material affixed in a spaced-apart position above the solar collector by means of a stand-off material; an insulated material positioned above the manifolds; and an arcuate member adhered between the sheet of transparent material and the strip of material and positioned over one of the manifolds to prevent debris from being deposited between the manifold and the solar collector. Also described is a nipple formed in a cylindrical configuration with an exterior surface and a free end. Also described is coupling apparatus between a manifold having a cylindrical nipple and a solar collector having a cylindrical orifice. Also described is a manifold for connection to a solar collector having a plurality of orifices extending longitudinally therethrough.

Sadler, C.

1989-09-19

287

A solar collector design procedure for crop drying  

Directory of Open Access Journals (Sweden)

Full Text Available A design procedure was proposed for sizing solar-assisted crop-drying systems and assessing the combination of solar collector area and auxiliary energy needs that meets the requirements of the load. Two empirical correlations were compared for use with high thermal inertia solar collectors that are cheap and appropriate for rural areas. A case study as performed in the city of Campinas in southeastern Brazil. Grain drying with partial air heating by solar energy can provide an annual savings of 30% in fuel consumption for 1.80m² collector area during the drying of 1.2t of corn at 50ºC at a daily air rate of 1526.8 m³/day.

B. M. Santos

2005-06-01

288

Pyrolytic graphite collector development program  

Science.gov (United States)

Pyrolytic graphite promises to have significant advantages as a material for multistage depressed collector electrodes. Among these advantages are lighter weight, improved mechanical stiffness under shock and vibration, reduced secondary electron back-streaming for higher efficiency, and reduced outgassing at higher operating temperatures. The essential properties of pyrolytic graphite and the necessary design criteria are discussed. This includes the study of suitable electrode geometries and methods of attachment to other metal and ceramic collector components consistent with typical electrical, thermal, and mechanical requirements.

Wilkins, W. J.

1982-01-01

289

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

Science.gov (United States)

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…

Gallitto, Aurelio Agliolo; Fiordilino, Emilio

2011-01-01

290

Conceptual design of a hybrid thermal and photovoltaic receiver of an FMDF collector  

Energy Technology Data Exchange (ETDEWEB)

The optical characteristic of a Fixed Mirror Distributed Focus (FMDF) solar collector is used as a basis for the design of a hybrid thermal and photovoltaic (PV) receiver. The result provides another variation in energy conversion that an FMDF solar collector can conveniently perform. (author)

Sulaiman, M.Y.; Hlaing Oo, W.M.; Wahab, M.A.; Sulaiman, Z.A. [Pertanian Univ., Serdang, Selangor (Malaysia); Khouzam, K.Y. [Queensland Univ. of Technology, Brisbane, QLD (Australia)

1997-12-31

291

Conceptual design of a parabolic dish solar collector using simulation techniques  

Science.gov (United States)

The development of solar concentrators in recent years have produced a wide variety of collectors for the utilization of solar energy. This paper presents the simulation techniques used to predict the optical and thermal performance of a paraboloid of revolution type solar collector. Conceptual design of a dish concentrator with a fixed receiver size is obtained by parametrically examining the significant variables.

Gupta, B. P.; Buchholz, R. L.

1976-01-01

292

Installation package for concentrating solar collector panels  

Science.gov (United States)

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

1978-01-01

293

Installation Package for Concentrating Solar Collector Panels.  

Science.gov (United States)

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

1978-01-01

294

Thermal effects of a wall solar collector-storage cell of energy, like conditioning system in residential air-conditioning; Efectos termicos de una pared colector-acumulador de energia solar, como sistema de acondicionamiento en la climatizacion habitacional  

Energy Technology Data Exchange (ETDEWEB)

At UNJBG-CERT in Tacna, we count on a laboratory that in its architectonic development integrates a collector solar power accumulator all. It was built with granite. It is a part of an accumulation system of calorific energy as well as at the external surface is used as a collection plate of incidental solar energy, making possible with it a contribution of heat for convection, conduction and radiation. In this article, there are results of the behavior of the temperatures of the interior air in the laboratory in correlation with different temperature measurements in the external and internal surfaces of the wall. In the article. Also there are some theoretical and experimental comparative graphics between between external and internal temperatures and their fluctuation grade for 24-hour periods. (Author)

Rivasplata, C.

2008-07-01

295

DT results of TFTR's alpha collector  

International Nuclear Information System (INIS)

An escaping alpha collector probe has been developed for TFTR's DT phase to complement the results of the lost alpha scintillator detectors which have been operating on TFTR since 1988. Measurements of the energy distribution of escaping alphas have been made by measuring the range of alphas implanted into nickel foils located within the alpha collector. Exposed samples have been analyzed for 4 DT plasma discharges at plasma currents of 1.0 and 1.8 MA. The results at 1.0 MA are in good agreement with predictions for first orbit alpha loss at 3.5 MeV. The 1.8 MA results, however, indicate a large anomalous loss of partially thermalized alphas at an energy ?30% below the birth energy and at a total fluence nearly an order of magnitude above expected first orbit loss. This anomalous loss is not observed with the lost alpha scintillator detectors in DT plasmas but does resemble the anomalous delayed loss seen in DD plasmas. Several potential explanations for this loss process are examined. None of the candidate explanations proposed thus far are fully consistent with the anomalous loss observations

1996-01-01

296

Facade integration of polymeric solar collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present paper examines building integrated solar collectors with absorbers of polymeric materials. Efficiency measurements of façade-integrated collectors with non-selective black and spectrally selective coloured absorbers are carried out. The performance of the polymeric absorber was compared with solar glass and polycarbonate twin-wall sheets as collector cover. Simulations demonstrate a high solar fraction for a solar combisystem with façade collectors for a well-insulated h...

2005-01-01

297

Experimental parabolic trough collector performance characterization  

Energy Technology Data Exchange (ETDEWEB)

Experimental data from the Collector Module Test Facility (CMTF) at Sandia National Laboratories, Albuquerque, are used to develop a collector performance model and characterize three parabolic trough solar collectors. The independent variables used in the model are selected and fitted to the experimental data using a multiple linear regression technique. The collector model developed accounts for optical performance, including incident angle effects and thermal losses, both linear and non-linear.

Lukens, L.L.

1981-05-01

298

Asymmetric Laser Radiant Cooling in Storage Rings  

CERN Multimedia

Laser pulses with small spatial and temporal dimensions can interact with a fraction of the electron bunches circulating in Compton storage rings. We studied synchrotron dynamics of such bunches when laser photons scatter off from the electrons with energy higher than the synchronous energy. In this case of ‘asymmetric cooling', as shown theoretically, the stationary energy spread is much smaller than under conditions of regular scattering; the oscillations are damped faster. Coherent oscillations of large amplitude may be damped in one synchrotron period, which makes this method feasible for injection the bunches into a ring in the longitudinal phase space. The theoretical results are validated with simulations.

Bulyak, E V; Zimmermann, F

2011-01-01

299

Bondings for tubular solar collectors  

International Nuclear Information System (INIS)

We studied the following four models of constructing solar collectors: tubes bonded above the absorber plate, tubes bonded under the absorber plate tubes in-line with the absorber plate and bondless tubes in-line with the absorber plate. 2 refs, 6 figs

1988-01-01

300

Bondings for tubular solar collectors.  

Science.gov (United States)

We studied the following four models of constructing solar collectors: tubes bonded above the absorber plate, tubes bonded under the absorber plate tubes in-line with the absorber plate and bondless tubes in-line with the absorber plate. 2 refs, 6 figs. (...

M. S. Husain

1988-01-01

 
 
 
 
301

Modelling and optimisation of the operation of a radiant warmer.  

Science.gov (United States)

This paper presents numerical calculations of the temperature field obtained for the case of a neonate placed under a radiant warmer. The results of the simulations show a very non-uniform temperature distribution on the skin of the neonate, which may cause increased evaporation leading to severe dehydration. For this reason, we propose some modifications on the geometry and operation of the radiant warmer, in order to make the temperature distribution more uniform and prevent the high temperature gradients observed on the surface of the neonate. It is concluded that placing a high conductivity blanket over the neonate and introducing additional screens along the side of the mattress, thus recovering the radiation heat escaping through the side boundaries, helped providing more uniform temperature fields. PMID:24183644

Fic, Anna M; Ingham, Derek B; Ginalski, Maciej K; Nowak, Andrzej J; Wrobel, Luiz C

2014-01-01

302

Simulation of thermal performance of solar collector arrays  

Science.gov (United States)

A method is described for simulating the thermal performance of solar collectors by using an in-line heat source to simulate absorbed solar energy and a nonirradiated array to simulate heat losses, during tests of solar water heating systems. The mathematical relationships needed to operate an electric heat source in series with a nonirradiated array are developed, and consideration is given to the location of the heat source and arrays with collectors connected in parallel and series combinations. An analysis is presented of the effects on thermal performance of the mixed indoor-outdoor collector test procedures. Analytical and experimental results are presented which show that the net power output from a nonirradiated collector array in series with an electric heat source is in good agreement with that from an irradiated array. Location of the heat source downstream from the nonirradiated array results in closer agreement with the irradiated array thermal output as compared to locating the heat source upstream from the nonirradiated collector array. Results of tests of a domestic solar hot water system are consistent with the theoretical results.

Fanney, A. H.; Thomas, W. C.

1981-08-01

303

Design Support System for Parabolic Trough Solar Collector  

Directory of Open Access Journals (Sweden)

Full Text Available Parabolic Trough Collector (PTC is special kind of heat exchanger that is able to transfer solar radiation energy to fluid medium that flow through it. Designing a PTC for a specific working condition requires determination of several parameters and referring to a number of design standards and handbooks. Hence, a design support system is required to determine the necessary parameters and simulate different working conditions. Although, a number of design support systems for solar collectors are available in the market, they are either expensive or limited to certain types of solar collectors. This study presents an in-house design simulation software for parabolic trough collector. The simulation software was coded in Microsoft Visual Studio.Net 2010. Through its Graphical User Interface (GUI, the software allows the user to give input parameters, explore built in standards and review outputs. The output parameters include geometric design parameters, heat losses coefficient and efficiencies. The output parameters are important in the initial stage of designing parabolic trough collectors to reduce design time and effort. The results of the simulation software are validated with published experimental and analytical results.

Abraham D. Woldeyohannes

2012-01-01

304

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2012-01-01

305

Radiant smiles everywhere - before the Chernobyl accident  

International Nuclear Information System (INIS)

The business reports presented by the Federal German electric utilities for 1985 are almost all simply brillant. Electricity consumption has been going up, some of the utilities even can boast about rates kept constant over the year. But before the printed business reports could be presented to the meetings of shareholders, a nasty cloud threw a dark shadow over all the brilliant results. The Chernobyl accident made some of the hymns over the nuclear electricity increases and nuclear power in general sound rather queer. Could we do without this energy source. Substituting nuclear power would yearly require: 28 million t of oil, or 41 million t of hard coal, or 142 million t of browncoal, or 38 thousand million cubic metres of natural gas. Extrapolating current conditions and assuming best achievements, renewable energy sources might be able to meet 6 p.c. of the primary energy demands by the year 2000. (orig./HP)

1986-01-01

306

Development of an improved photovoltaic/thermal (PV/T) solar collector with bi-fluid configuration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Solar energy is by far the largest source of renewable energy which the direct utilization of the energy is generally carried out via thermal or photovoltaic (PV) type of solar collectors. The integration of both types of solar collector results in an increase in the overall performance of the collector per unit area and known as a photovoltaic/thermal (PV/T) solar collector. The research to date has tended to focus on either water or air as the working fluid. This paper presents a developmen...

2013-01-01

307

Fresnel concentrating collector  

Science.gov (United States)

An advanced point focusing solar technology demonstrated potential for near term commercialization as a renewable energy technology. The design features combine to produce a highly efficient, low cost, safe, adaptable, durable system which is simple to manufacture, install and maintain.

Rogers, W.; Borton, D.; Rice, M.; Rogers, R.

1981-01-01

308

Solar-Collector Radiometer  

Science.gov (United States)

Water-cooled Kendall radiometer measures output of solar energy concentrators. Unit measures irradiance up to 30,000 solar constants with 1 percent accuracy and responds to wavelengths from ultraviolet to far infrared.

Kendall, J. M., Jr

1984-01-01

309

The Collector of a Megawatt Gyrotron with a Static Nonadiabatic Magnetic Field  

Science.gov (United States)

We have developed the concept and design of a collector with a static nonadiabatic magnetic field, which allow one to exclude the influence of pulsed thermal loads and accumulation of nonelastic deformations in the collector body, as well as achieve the nearly uniform distribution of the heat release power density over its surface for an energy load of about 500 W/cm2. Such a collector is characterized by moderate criticality with respect to variations in the electron energy distribution and the effect of an external scattering magnetic field. The decrease in criticality is achieved by choosing the cylindrical shape of the collector and using two pairs of counter-wound low-power solenoids in the collector system.

Denisov, G. G.; Manuilov, V. N.

2013-11-01

310

A collector system for the solar thermal power generation  

International Nuclear Information System (INIS)

Collector system of solar energy which consists of a cylindrical parabolic reflector and a receiver assembly have been designed and constructed for power generation. The receiver system has an aperture parallel to the axis of the cylindrical reflector. The tilt of a north-south axis of the collector system is adjusted manually and an east-west axis of the system is made track the sun automatically. The smaller system having an effective surface area of 5.5m2 has a focusing ratio of 18 and the larger one of 55m2 surface area has about 100. Various characteristics have been measured and the results are discussed. (author)

1979-01-01

311

Design and testing of a radiant high temperature burner  

Energy Technology Data Exchange (ETDEWEB)

Since 1978 a thermionic energy converter (TEC) for terrestrial applications is being developed within the research-project High Temperature Constructions. Basically the TEC is a diode, which converts heat directly into electricity. The TEC imposes large demands on its heat-source: it must deliver a heat-flux of 1.5 kW (340 kW m{sup -2}) at a temperature of 1723 K. The heat-source has to be a burner fuelled by natural gas. The TEC and burner will form a complete unit, which can be used for heating of (green)houses. The purpose of this project is to design and build a test-furnace for the TEC. For the heat-source, the concept of a porous radiant burner is chosen. The porous body is made of partially stabilized zirconia. Much attention is paid to the stabilization of the combustion in the ceramic, so that flash-back can not occur. Further the burner is able to withstand severe thermal cycling. On top of the burner a simple but effective furnace can be placed. This furnace can be used to test the TEC. The performance of the burner is monitored experimentally. The highest temperature reached is 1965 K at an input power of 9.5 kW. If the TEC will be placed in the furnace, it will receive 0.35 kW under these circumstances. For the objective of 1.5 kW, the burner temperature needs to be increased to 2273 K. To increase the burner temperature, the combustion air can be enriched with oxygen. The materials used in the construction performed satisfactory, but they suffered from thermal shock and corrosion. New materials must be sought or the thermal shock must be less severe. For the future the design must be combined with preheating of the combustion air, leading to a burner coupling high temperature with uniform heating. Apart from heating the TEC, the design can be adapted to fields where similar features are needed like environmental applications. 7 tabs., 41 figs., 43 refs., 7 appendices

Sampers, W.

1993-11-15

312

A Concentrated Solar Power Unit Collector’s Efficiency under varied wind speeds  

Directory of Open Access Journals (Sweden)

Full Text Available Concentrated Solar Power (CSP harnesses the sun?s solar energy to produce electricity. This report provides a technical analysis of the potential for CSP to provide low cost renewable electricity in Bhopal (M.P. and outlines the impact of varied wind speeds on its collector?s efficiency. Yields of CSP Plants depend strongly on site-specific meteorological conditions. Meteorological parameters that can influence the performance of CSP plant are Direct Normal Irradiance (DNI, wind, ambient air temperature and humidity. The concentrated solar thermal power system constructed for this system follows that of conventional design of a parabolic concentrator with the receiver placed along the line between the centre of the concentrator and the sun. The concentrator receives approximately 1124.82W/m2 of solar insolation (dependent upon time of year, which is concentrated and reflected to the receiver. By concentrating the incoming radiation, the operating temperature of the system is increased significantly, and subsequently increases the efficiency of the conversion from sunlight to electricity. For the current system, with a concentration ratio of 495, the concentrator is theoretically capable of producing temperature upwards to 712 degrees centigrade. It was found that the collector (concentrator + receiver yields an efficiency of 95.6 percent. This study investigates the potential for our intervention to accelerate the deployment of small-scale concentrated solar power (CSP in various parts of Bhopal (M.P.

Ajay Vardhan

2013-10-01

313

Air/liquid collectors : September 1997  

DEFF Research Database (Denmark)

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 equation will allow the manufactures to optimize this kind of systems.

Jensen, Søren �stergaard; Olesen, Ole

1997-01-01

314

Active solar collectors and their applications  

CERN Document Server

1. Survey of Solar Equipment and Applications2. Solar Geometry3. Insolation Data and Models4. Collector Efficiency and Collector Testing5. Fundamentals of Optics for Solar Collectors6. Optics of Nontracking Collectors7. Tracking Concentrator Types8. Optical Analysis and Optimization of Parabolic Reflectors9. Heat Transfer in Solar Collectors10. Heat Transfer Factors11. System Models12. Applications13. Practical Considerations14. Economic Analysis15. System OptimizationAppendix A. NomenclatureAppendix B. UnitsAppendix C. Properties of MaterialsAppendix D. Meteorological DataAppendix E. Circumso

Rabl, Ari

1985-01-01

315

Glass heat pipe evacuated tube solar collector  

Energy Technology Data Exchange (ETDEWEB)

A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.

McConnell, R.D.; Vansant, J.H.

1984-10-02

316

Glass heat pipe evacuated tube solar collector  

Energy Technology Data Exchange (ETDEWEB)

A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.

McConnell, Robert D. (Lakewood, CO); Vansant, James H. (Tracy, CA)

1984-01-01

317

Test of EBS-HP-collector/EES-solar boiler. Testen aan EBS-HP-collector/EES-zonneboiler  

Energy Technology Data Exchange (ETDEWEB)

Under the authority of the Project Control Agency for Energy Research (PEO, Netherlands) measurements have been executed on the by EBS developed HP-collector and on the heat storage system of the EES solar boiler. The efficiency characteristics of the HP-collector were determined under the TPP solar simulator according to an international test procedure. Therefore the results of the measurements are reported in English. Characteristic for the collector is the applied double coverage: on the outside iron-free glass and on the inner side a tense tedlar foil. The tested solar boiler reservoir is meant to replace electric boilers. A feasibility study executed by the company EBS (now EES), concluded that the extra charges of such a reservoir compared to a conventional electric boiler are low. The decision was taken to elaborate and test the concept. The aim of testing the heat reservoir was determining heat losses during rest, electric heating and flow of the heat exchanger from the collector. The first part of this report discusses the testing of the solar boiler reservoir. The second part deals with the measurement results of the test of the HP-collector.

Kortschot, J.; Kratz, P.; Havinga, J.

1987-01-01

318

Desiccant cooling using unglazed transpired solar collectors  

Energy Technology Data Exchange (ETDEWEB)

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% more than that required for the glazed collector, the cost of the unglazed collector array was 44% 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. 8 refs.

Pesaran, A A [National Renewable Energy Lab., Golden, CO (United States); Wipke, K [Stanford Univ., CA (United States)

1992-05-01

319

Performance Evaluation of a Nanofluid (CuO-H2O Based Low Flux Solar Collector  

Directory of Open Access Journals (Sweden)

Full Text Available As the fossil fuels are depleting continuously, we know that solar energy harvesting is a significant potential area for new research dimensions. Sun provides us about 1.9 x 108TWh/yr on the land, of which 1.3 x 105 TWh]/yr energy is used. In order to make much use of solar energy on the earth, solar energy harvesting into more usable form (e.g. heat or electricity by using solar energy collectors is important aspect. A solar collector [1] is a device which transfers the collected solar energy to a fluid passing in contact with it. The performance of collector does not only depends upon how effective the absorber is, but also on how effective are the heat transfer and thermal properties (e.g. thermal conductivity, heat capacity of the fluid which is being used. The absorption properties of the fluids generally used in solar collectors are very poor which in turn limits the efficiency of the solar collector. So, there is a need to use energy efficient heat transfer fluids for high efficiency and performance. A relatively new attempt has been made to increase the performance of the solar collector by using nanofluids. Recently developed a new class of working fluids called Nanofluids, found to be possessing better thermal properties over the hosting fluids, can be a good option in the solar collector [5]. In our research work the CuO-water based nanofluid has been tested in the solar collector and their performance is investigated. It has been found that efficiency if the solar collector is increased by 4-6% compared to water

Lal Kundan

2013-04-01

320

Combination of solar collectors and ground-source heat pump for small buildings  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The combination of solar heat and ground-source heat pumps in dwellings gives opportunities for optimising the use of renewable energy sources and minimize the share of bought energy. Solar collectors in the system may give advantages for the operational conditions both for the solar collectors and for the heat pump. The aim of this project was to analyse different variables such as energy demand, building types, climate, geological conditions, system design and control. The study has been ca...

Kjellsson, Elisabeth; Hellstro?m, Go?ran; Perers, Bengt

2005-01-01

 
 
 
 
321

The implementation of the regulations on solar collectors in buildings  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The use of solar energy constitutes a great concern of national and international bodies, as a result of a strategic policy towards green energy consumption. The Portuguese regulations on building thermal behaviour and energy efficiency, recently enacted by the Portuguese Government, in line with the European Union Directive 2002/91/CE, have introduced the obligatory use of solar collector technology for hot water production applied to new building projects and to some important retrofit work...

Abreu, Isabel; Oliveira, Rui

2008-01-01

322

The implementation of regulations on solar collectors in buildings  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the beginning of this decade, the Portuguese Program E4 – Energy Efficiency and Endogenous Energies have proposed an ambitious goal of 1 million m2 of solar collector area in Portugal until 2010. To cope with this, it was implemented in 2001 by Portuguese Government the National Program Solar Hot Water for Portugal (IP-AQSpP). The Portuguese new Thermal Regulations (RCCTE) opens to all constructions partners a new opportunity for implementing more strongly renewable energy technologies i...

Abreu, Isabel; Oliveira, Rui

2008-01-01

323

Radiant heat exchange measurements for Tore Supra  

International Nuclear Information System (INIS)

In order to minimize the energy consumption of the low temperature cryogenic system connected to the superconducting magnet of TORE-SUPRA, heat exchange from thermal radiation between the vacuum vessels and the thermal shields has been studied. Accordingly large scale cold and hot walls of T.S. have been simulated in a model with reduced dimensions. In this model, the experiment consists in the measurement of the thermal radiated power between two concentric cylindrical surfaces of stainless steel under vacuum conditions. The temperature of the external cylinder was kept constant at 80 K. The internal cylinder was bakeable up to 2500C. Various surface treatments were applied on the two cylinders (mechanical polishing and metal deposition of Al, Ag, Ni)

1984-01-01

324

Radiant barrier field tests in army family housing units at Fort Benning, Georgia  

Energy Technology Data Exchange (ETDEWEB)

The US Army initiated a project to make measurements of heating and cooling energy in occupied Army housing units to determine the effect of radiant barriers (RBs) on energy consumption at Ft. Benning, in Columbus, GA. One side (1700 ft{sup 2}) of each of five duplexes was used as a control (no RB was installed in it) while the other side had perforated RB laid on top of the existing estimated R-11 fiberglass loose-fill attic insulation in the middle of July. The RBs were removed in the middle of January. All houses were instrumented with data logging equipment which measured air conditioner and gas furnace energy usages. Cooling season measurements showed that submetered air conditioner (A/C) KWh-meter data read on a weekly basis did not describe the performance of the RBs. Occupant lifestyle in general, and a dirty air filter at one site, nullified direct meter reading comparisons. Attic heat flow and temperature measurements revealed that the RBs were effective at all sites. Extensive regression analyses showed that savings were indeed obtained. Using the regression results with published temperature bin data for Ft. Benning gave estimated annual cooling savings from HRB use ranging from 253 to 1354 KWh, or from 3 to 17%. Heating energy usage did not appear to be affected by lifestyle as much as was cooling energy usage. HRBs gave an annual space heating savings of about 42 to 70 CCF of gas (11 to 19%) using averaged daily data to generate regression models. Measured emissivity values for samples of the horizontally mounted radiant barrier material showed essentially no change for the six-month period during which they were installed in the five test units. Although RBs were effective at Ft. Benning, it is recommended that more testing be done, especially in colder climates and in drier desert climates, before any general conclusions regarding the use of RBs in Army housing are formulated.

Levins, W.P.; Herron, D.

1990-01-01

325

Terrestrial photovoltaic collector technology trends  

Science.gov (United States)

Following the path of space PV collector development in its early stages, terrestrial PV technologies based upon single-crystal silicon have matured rapidly. Currently, terrestrial PV cells with efficiencies approaching space cell efficiencies are being fabricated into modules at a fraction of the space PV module cost. New materials, including CuInSe2 and amorphous silicon, are being developed for lowering the cost, and multijunction materials for achieving higher efficiency. Large grid-interactive, tracking flat-plate power systems and concentrator PV systems totaling about 10 MW, are already in operation. Collector technology development both flat-plate and concentrator, will continue under an extensive government and private industry partnership.

Shimada, K.; Costogue, E.

1984-01-01

326

Dry-type dust collectors  

Energy Technology Data Exchange (ETDEWEB)

The authors discuss bag filters, which presently account for approximately three quarters of all dust collectors. The filter cloths for bag filters consist of either a woven material or a felt. Collected dust is removed from the filter cloth by mechanical shaking, pulse jets or backwashing. The authors describe the application of bag filters to cupola off-gas, coal-fired boiler flue gas, and the pneumatic transport of fly ash. 2 references.

Yoneda, K.; Takaishi, M.

1984-01-01

327

Optimum outlet temperature of solar collector for maximum work output for an Otto air-standard cycle with ideal regeneration  

Energy Technology Data Exchange (ETDEWEB)

The optimum solar collector outlet temperature for maximizing the work output for an Otto air-standard cycle with ideal regeneration is investigated. A mathematical model for the energy balance on the solar collector along with the useful work output and the thermal efficiency of the Otto air-standard cycle with ideal regeneration is developed. The optimum solar collector outlet temperature for maximum work output is determined. The effect of radiative and convective heat losses from the solar collector, on the optimum outlet temperature is presented. The results reveal that the highest solar collector outlet temperature and, therefore, greatest Otto cycle efficiency and work output can be attained with the lowest values of radiative and convective heat losses. Moreover, high cycle work output (as a fraction of absorbed solar energy) and high efficiency of an Otto heat engine with ideal regeneration, driven by a solar collector system, can be attained with low compression ratio.

Eldighidy, S.M. (Sultan Qaboos Univ., Al-Khod (Oman))

1993-09-01

328

Modeling Heat Flow In a Calorimeter Equipped With a Textured Solar Collector  

Science.gov (United States)

Heat engines are being considered for generating electric power for minisatellite applications, particularly for those missions in high radiation threat orbits. To achieve this objective, solar energy must be collected and transported to the hot side of the heat engine. A solar collector is needed having the combined properties of high solar absorptance, low infrared emittance, and high thermal conductivity. To test candidate solar collector concepts, a simple calorimeter was designed, manufactured, and installed in a bench top vacuum chamber to measure heat flow. In addition, a finite element analysis model of the collector/calorimeter combination was made to model this heat flow. The model was tuned based on observations from the as-manufactured collector/calorimeter combination. In addition, the model was exercised to examine other collector concepts, properties, and scale up issues.

Jaworske, Donald A.; Allen, Bradley J.

2001-01-01

329

Measurement of radiant heat gain from office equipment using a scanning radiometer  

Energy Technology Data Exchange (ETDEWEB)

Measurement of the radiant heat loss from office equipment and other equipment in buildings is necessary in order to make accurate assessments of their impact on cooling loads. This paper describes a new method of measuring this heat loss that was developed as a part of ASHRAE research project RP-822, Test Method for Measuring the Heat Gain and Radiant/Convective Split from Equipment in Buildings. The measurement method, referred to here as the scanning radiometer method, utilizes a relatively inexpensive, off-the-shelf net radiometer to make the measurements. The radiometer scans a hemispherical area around the equipment being evaluated, and, by integrating the net radiant flux through this area, the total radiant flux from the equipment to the room is measured. This method automatically compensates for other radiant fluxes in the room. The radiometer sensor must be calibrated for this application, and a simple device was developed for this purpose. Before various equipment items were evaluated for radiant heat loss using the scanning radiometer method, it was tested by measuring the radiant heat losses from a heated flat plate and a heated sphere. The radiant heat loss from these well-defined objects could be calculated accurately and compared to the results obtained with the scanning radiometer measurement. In both cases, the scanning radiometer method yielded results well within the range of uncertainty in the calculated radiant heat losses.

Jones, B.W.; Hosni, M.H.; Sipes, J.M. [Kansas State Univ., Manhattan, KS (United States)

1998-10-01

330

Phase-change thermal energy storage: Final subcontract report  

Energy Technology Data Exchange (ETDEWEB)

The research and development described in this document was conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy absorbed by the solar thermal receiver is transported to the conversion process by a circulating working fluid. Receiver temperatures range from 100{degree}C in low-temperature troughs to over 1500{degree}C in dish and central receiver systems. 12 refs., 119 figs., 4 tabs.

1989-11-01

331

An air-cooled solar collector using all-cylindrical elements in a low-loss body  

Energy Technology Data Exchange (ETDEWEB)

A novel IX air-cooled solar collector has a phenolic polymer structural foam body, a black painted fiberglass mat absorber and a coplanar, parallel, close-packed array of evacuated cylindrical glass tubes for a cover. Modeling suggests, and measurements confirm, high efficiency performance as well as a substantial dispersion of performance characteristic arranged so that the specific temperature difference increases as the radiant intensity decreases. This dispersion suggests greatly improved cloudy weather performance. In a steady state simulation at full sun under northern midwinter conditions this collector can deliver a minimum of 1.9 times mor heat per day to Glauber's Salt storage than can a IX double glazed water-cooled collector with a non-selective black flat absorber plate. Under cloudy conditions this advantage ratio rises to 12.1 at 5/13 sun. Effective heat collection continues at intensities as low as 3/13 sun. Under summertime conditions the collector can operate an absorption air conditioner at 6/13 sun.

Herrick, C.S.

1983-03-01

332

Radiant heat test of Perforated Metal Air Transportable Package (PMATP)  

International Nuclear Information System (INIS)

A conceptual design for a plutonium air transport package capable of surviving a 'worst case' airplane crash has been developed by Sandia National Laboratories (SNL) for the Japan Nuclear Cycle Development Institute (JNC). A full-scale prototype, designated as the Perforated Metal Air Transport Package (PMATP) was thermally tested in the SNL Radiant Heat Test Facility. This testing, conducted on an undamaged package, simulated a regulation one-hour aviation fuel pool fire test. Finite element thermal predictions compared well with the test results. The package performed as designed, with peak containment package temperatures less than 80 C after exposure to a one-hour test in a 1000 C environment

2003-01-01

333

Creating Radiant Thinking of Young Children through Mind Mapping  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mind mapping is a presentation form of radiant thinking, utilizing lines, colors, characters, numbers, symbols, image, pictures or keywords, etc. to associate, integrate and &l...

Wen Cheng Wang; Chung-Chieh Lee; Ying-Chien Chu

2011-01-01

334

Radiant science, dark politics: a memoir of the nuclear age  

International Nuclear Information System (INIS)

The reviewer describes Radiant Science, Dark Politics: A Memoir of the Nuclear Age in contrast to a memoir by James R. Killian, Jr., a contemporary of Kamen. Kamen, co-discoverer of carbon-14 and a valued member of the Berkeley Radiation Laboratory, was fired in 1944 and blackballed as a security risk. Rehabilitated by the end of the war, his continued fight against political injustice through the McCarthy era colors the book and, for the reviewer, makes it self-serving. Kamen's later scientific work reflected his desire to work alone rather than in collaboration

1985-01-01

335

Drying by means of solar collectors  

Energy Technology Data Exchange (ETDEWEB)

Solar collectors may be covered with either transparent plastic plates or dark Eternit, or else black sheet metal. Evaluation of 57 solar collectors showed that collector surface averages 202 m/sup 2/ (70 - 460 m/sup 2/). The ratio between hay born surface and collector surface is 1 : 1.8 with polyester and 1 : 2.4 with Eternit roofs. Prices for collectors range between 30 and 35 Swiss Francs/sqm with roof-integrated facilities and c. 50 Swiss Francs/sqm with on-roof constructions. Sheet metal and Eternit converings are cheaper than polyester. Out of the total of solar collectors studied one did not meet the expectations, two facilities just fell short of them, 28 fulfilled them and 23 exceeded tham. Dust depositing and condensation water formation posed some problems.

Nydegger, F.; Klaeger, P.

1983-01-01

336

Dual curvature acoustically damped concentrating collector  

Science.gov (United States)

The design and performance parameters of a dual curvature, concentrating solar collector are investigated. The reflector of the solar collector is achieved with a stretched film reflective surface that approximates a hyperbolic paraboloid and is capable of line focusing at concentration ratios ranging from 10 to 20X. A prototype collector was designed based on analytical and experimental component trade off activities as well as economic analyses of solar thermal heating and cooling systems incorporating this type of collector. A prototype collector incorporating six 0.66 x 1.22 m (2 x 4 ft) was fabricated and subjected to a limited thermal efficiency test program. A peak efficiency of 36% at 121 C (250 F) was achieved based upon the gross aperture area. Commercialization activities were conducted, including estimated production costs of $134.44/sq m for the collector assembly (including a local suntracker and controls) and $24.33/sq m for the reflector subassembly.

Smith, G. A.; Rausch, R. A.

1980-05-01

337

Load and Season Adapted Solar Collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In Sweden solar irradiation and space heating loads are unevenly distributed over the year. Domestic hot water loads may be nearly constant. Test results on solar collector performance are often reported as yearly output of a certain collector at fixed temperatures, e g 25, 50 and 75 C. These data are not suitable for dimensioning of solar systems, because the actual performance of the collector depends heavily on solar fraction and load distribution over the year.At higher latitudes it is di...

Nordlander, Svante; Ro?nnelid, Mats; Karlsson, Bjo?rn

2000-01-01

338

Stainless steel flat-plate solar collectors  

Energy Technology Data Exchange (ETDEWEB)

Experiments in Sweden to produce an efficient selective stainless steel solar-collector absorber with good aging properties show that smooth collector surfaces in water-cooled collectors can have higher efficiencies than raw, uneven surfaces. This is because an uneven surface loses more heat by convection than does a smooth surface. Thermal oxidation under vacuum produces a smooth absorber surface on ferritic stainless steel. 9 figures.

Hultquist, G.

1982-01-01

339

Electrochemically Stable Cathode Current Collectors for Rechargeable Magnesium Batteries  

Energy Technology Data Exchange (ETDEWEB)

Rechargeable Mg batteries are attractive energy storage systems and could bring cost-effective energy solutions. Currently, however, no practical cathode current collectors that can withstand high voltages in Mg2+ electrolytes has been identified and therefore cathode research is greatly hindered. Here we identified that two metals, Mo and W, are electrochemically stable through formation of surface passive layers. The presented results could have significant impacts on the developments of high voltage Mg batteries.

Cheng, Yingwen; Liu, Tianbiao L.; Shao, Yuyan; Engelhard, Mark H.; Liu, Jun; Li, Guosheng

2014-01-01

340

Nanofluid optical property characterization: towards efficient direct absorption solar collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Suspensions of nanoparticles (i.e., particles with diameters < 100 nm) in liquids, termed nanofluids, show remarkable thermal and optical property changes from the base liquid at low particle loadings. Recent studies also indicate that selected nanofluids may improve the efficiency of direct absorption solar thermal collectors. To determine the effectiveness of nanofluids in solar applications, their ability to convert light energy to thermal energy must be known. That i...

2011-01-01

 
 
 
 
341

Nanofluid optical property characterization: towards efficient direct absorption solar collectors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Suspensions of nanoparticles (i.e., particles with diameters < 100 nm) in liquids, termed nanofluids, show remarkable thermal and optical property changes from the base liquid at low particle loadings. Recent studies also indicate that selected nanofluids may improve the efficiency of direct absorption solar thermal collectors. To determine the effectiveness of nanofluids in solar applications, their ability to convert light energy to thermal energy must be known. That is, their absorption of...

2011-01-01

342

Comparative Study of Single Pass Collector and Double Pass Solar Collector Filled with Porous Media  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This research reports a comparative study of the conventional single pass flat plate collector and the double pass solar collector filled with porous media such as gravel and metal chips at the lower channel of absorbing unit. The component materials, design, performance efficiencies, capabilities and the application of the solar collectors are presented to show various disparities that exist between the collectors. Emphasis was laid on the multi-pass approach as a gate way to future de...

2013-01-01

343

Determination of solar collector loss coefficients  

Energy Technology Data Exchange (ETDEWEB)

Analytical and three experimental determinations of the collector loss coefficient are compared. Measurement of absorber temperature during steady state testing merits consideration in determining the heat loss coefficient.

Parker, B.F.; Colliver, D.G.; Walton, L.R.

1984-01-01

344

Dust explosions in an industrial dust collector  

Energy Technology Data Exchange (ETDEWEB)

Pressures generated by dust explosions ina commercial dust collector have been measured. The dust clouds of polyethylene, phenolic resin, toner and aspirin were formed while the collector was operating under normal working conditions, i.e. dusts were dislodged from the filter elements inside the collector by pulsed reversed-air jets. The dust clouds were ignited by a 30 g charge of black powder in the hopper beneath the collector. The vented explosion pressures measured under these conditions provide a realistic guide to the explosion pressures the filter may have to withstand in practice. (orig./PW).

Lunn, G.; Cairns, F.

1986-02-01

345

Testing of BYS (Nepal) solar collectors  

Energy Technology Data Exchange (ETDEWEB)

The work sheet contains the test reports of four different types of collectors. Each report contains a description of the collector regarding the absorbing material, the absorbing layer, covering, characteristics of the construction, heat transporting agents, the angle of inclination of the position, and the test location. Furthermore, the monthly gross heat yields in terms of kWh per m/sup 2/ collector surface are determined, as well as the yearly efficiency and the k-values during the night. Finally, the constructive arrangement of each collector is described.

Meier, U.

1983-03-01

346

Radiant heat transfer modeling in electrorheological fluids: Treatment as an absorbing medium  

Energy Technology Data Exchange (ETDEWEB)

Radiation heat transfer control utilizing the unique properties of electrorheological (ER) fluids has recently been the subject of considerable interest as an innovative new area of research. While much work has been done to demonstrate the concept and show the potential for radiation transmittance control, little has been done to specifically identify the fundamental radiation transport mechanism involved. This paper identifies particle absorption as the dominant mode for attenuation of radiant energy from the range of 500 nm to 800 nm incident upon an ER fluid made of micron sized zeolite particles. Furthermore, appropriate models are developed based on absorption theory to predict radiation heat transfer through a composite window featuring a layer of ER fluid. The levels of extinction predicted by these models are compared to data obtained by experimental measurement, with excellent agreement shown.

Hargrove, J.B.; Lloyd, J.R.; Radcliffe, C.J. [Michigan State Univ., East Lansing, MI (United States). Dept. of Mechanical Engineering

1996-12-31

347

Simulation of air collector plants with T{sup *}SOL; Simulation von Luftkollektoranlagen in T{sup *}SOL  

Energy Technology Data Exchange (ETDEWEB)

Air collector systems are implemented in Europe and the U.S. for some time. Air collector systems especially are suitable for solar support of controlled residential ventilation systems, for the support of solar air heating systems and in particular for heating buildings. The company Valentin EnergieSoftware GmbH (Berlin, Federal Republic of Germany) developed the software module 'Solar air collectors' in order to support the planners in the dimensioning, design and simulation of these solar air heating systems. The simulation considers the thermal behaviour and the capacity of the building. A combination of the solar air collector system and potable water heating is possible.

Dunnett, David; Engelhardt, Sebastian [Dr. Valentin EnergieSoftware GmbH, Berlin (Germany)

2010-07-01

348

Effects of low reflection on the collector and source sheaths of a finite ion temperature plasma  

International Nuclear Information System (INIS)

The region between a Maxwellian plasma source and an absorbing surface which reflects a fraction of the incident ions is modeled numerically with dynamic, electrostatic particle simulation and theoretically with a static, kinetic plasma-sheath model. The fraction /zeta/ of ions reflected is varied from 0 to 0.6 which generally increases both the potential drop from the source to the collector and the energy transported to the collector surface. Results from both models agree well when the fraction reflected is less than 0.4 for full energy transfer to reflected ions. With larger fractions and with slightly less than full reflected energy, simulations show an ion-ion two-streaming interaction which slightly reduces the collector potential drop and decreases the ion energy deposited on the collector surface relative to predictions from the static theory. According to theory, for a deuterium-tritium plasma, a collector material causing the reflected ion fraction to be /zeta/ = 0.2 with full reflected energy increases the magnitude of collector potential by 12% and the ion energy deposited by 6% over those predicted when /zeta/ = 0

1988-01-01

349

Radiant type kerosene flare heater (OFH-Z8C)  

Energy Technology Data Exchange (ETDEWEB)

New developed radiant type kerosene heater (OFH-Z8C) was presented, which was featured by the beautiful flame of a kerosene burner. To maintain the beautiful flame, a burner with a new rotary atomizer was adopted, which was developed to prevent oil leakage and to improve its performance. To reduce carbon monoxide emissions, a burner head with a notch and ring-formed flame holes was developed, and a simple heating element with an excellent durability and beautiful uniform brightness was also developed. Heat capacity of the ferric stainless steel heating element was lowered as possible to reduce carbon monoxide emissions under the same radiant efficiency. Semicylindrical element configuration was also adopted considering uniform red heat, brightness and thermal deformation. The combustion was controlled giving priority on a stability to maintain beautiful flame, while like fan type kerosene heaters, safety devices such as a flame sensor and emergency shut-out device were attached to the heater. 5 refs., 16 figs., 4 tabs.

Naganuma, Hisao; Sugimoto, Minoru; Numao, Masanobu; Morishima, Masayuki; Okada, Masafumi (Sanyo Electric Co., Ltd., Osaka (Japan))

1989-06-01

350

Hybrid photovoltaic/thermal (PV/T) collector coupled with a compound parabolic concentrator (CPC)  

Energy Technology Data Exchange (ETDEWEB)

Hybrid Photovoltaic/Thermal (PV/T) conversion is a relatively new and promising technology for the production of both electrical and thermal energy simultaneously. A number of theoretical and experimental studies have been reported in the past on PV/T systems with air and liquid as heat transfer fluid. Studies on PV/T collectors are being made at Indian Institute of Technology in collaboration with All India Council of Technical Education (AICTE), New Delhi. Earlier, present authors have carried out detailed simulation studies on PV/T air heating collectors and have shown that hybrid PV/T systems have great potential in terms of their system efficiencies. It is further envisaged that the efficiency of a hybrid PV/T collector can be enhanced by its effective coupling with a compound parabolic concentrator (CPC). In the present investigation a theoretical analysis has been presented to study the performance of a hybrid PV/T collector coupled with a CPC. In the design, several CPC troughs are combined in a single collector panel. The absorber of the hybrid PV/T collector under investigation consists of an array of solar cells for generation of electricity, while collector fluid circulating past the absorber provides useful thermal energy as in a conventional flat plate collector. In the analysis, it is assumed that solar cell efficiency can be represented by a linear decreasing function of its temperature. Energy balance equations have been developed for various components of the system. Based on the developed analysis both thermal and electrical performance of the system as a function of system design parameters are presented and discussed. Results have been presented to compare the performance of hybrid PV/T collector coupled with and without CPC.

Garg, H.P.; Adhikari, R.S.

1998-07-01

351

16 CFR Figure 4 to Subpart A of... - Flooring Radiant Panel Tester Schematic Low Flux End, Elevation  

Science.gov (United States)

...2010-01-01 false Flooring Radiant Panel Tester Schematic Low Flux End, Elevation 4 Figure 4 to Subpart A of Part 1209 Commercial...A of Part 1209âFlooring Radiant Panel Tester Schematic Low Flux End, Elevation...

2010-01-01

352

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)

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.

1979-01-01

353

High concentration solar collector of the stepped spherical type: optical design characteristics.  

Science.gov (United States)

An analysis of the optical design characteristics of a new high concentration solar collector is presented. This type of collector consists of spherical segments that are sections of a spherical cap by planes perpendicular to its axis. These ring-shaped spherical segments are so arranged along their common axis that the planes of their circles of least confusion are superposed. The optical characteristics and simulation of this system are developed to provide information for the engineering design of this type of solar energy collector system. The calculations are checked by a laser scanning onto a breadboard mock-up. PMID:20234654

Authier, B; Hill, L

1980-10-15

354

Heat transfer in a low latitude flat-plate solar collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 geometri...

2012-01-01

355

Use of solar parabolic trough collectors for hot water production in Cyprus. A feasibility study  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with a feasibility study for the use of solar Parabolic Trough collectors for hot water production in Cyprus. An analysis is carried out for two types of applications, domestic and hotel. The systems are optimised using the F-chart program and compared to similar systems using Flat Plate Collectors. It is shown that for large scale water production the Parabolic Trough Collectors are more efficient than the Flat Plate ones. The life cycle savings from their use as applied to a real life situation is almost 5,350 Cyprus Pounds with 60% of the available solar energy being utilised. (author).

Kalogirou, S.A. (Higher Technical Inst., Nicosia (Cyprus)); Lloyd, S. (Polytechnic of Wales, Glamorgan (United Kingdom). Dept. of Science and Chemical Engineering)

1992-04-01

356

Testing and thermal modeling of radiant panels systems as commissioning tool  

International Nuclear Information System (INIS)

This paper presents the results of a study performed to develop a thermal modeling of radiant panels systems to be used in situ, as diagnosis tool in commissioning processes to determine the main operating conditions of the system in cooling or heating mode. The model considers the radiant panels as a finned heat exchanger in dry regime. By using as inputs the ceiling and room dimensions, the radiant ceiling material properties and the measurements of air and water mass flow rates and temperatures, the model is able to calculate the radiant ceiling capacity, ceiling surface average temperature, water exhaust temperature and resultant temperature as a comfort indicator. The modeling proposed considers combined convection, perforation effect and a detailed radiative heat exchange method for radiant ceiling systems. An example of each system considered in this study is shown, illustrating the validation of the model. A sensitive analysis of the model is performed.

2010-12-01

357

Segment mirror collector (Part 2)  

Energy Technology Data Exchange (ETDEWEB)

In order to improve the performance and reduce the cost of collector subsystem in the solar-heat utilization system, the reduction of manufacturing cost of the field type segment mirror collector, decrease of the weight of equipment, simplification of construction method and sharp reduction of installation cost by shortening the construction period were tried. Among the heat-collecting characteristics, the optical efficiency was approximately 10% lowered and the heat loss from the heat-collecting part was 7 to 8% increased up to approximately 100 W/m/200/sup 0/C due to the decrease of tracking property caused by the difference among the individual mirror units. The quick deterioration of performance of the secondary lightconcentrating mirror is a problem. The cost reduction and simplification of construction method suffice the expectation as much as 70% though the reliability and performance are lowered a little. It seems that the construction method offers no problem and the operating procedure is appropriate. (1 ref, 8 figs, 4 tabs)

Sawada, Shinji; Sakuta, Hirokazu; Tani, Tatsuo

1986-12-01

358

Comparative Study of Single Pass Collector and Double Pass Solar Collector Filled with Porous Media  

Directory of Open Access Journals (Sweden)

Full Text Available This research reports a comparative study of the conventional single pass flat plate collector and the double pass solar collector filled with porous media such as gravel and metal chips at the lower channel of absorbing unit. The component materials, design, performance efficiencies, capabilities and the application of the solar collectors are presented to show various disparities that exist between the collectors. Emphasis was laid on the multi-pass approach as a gate way to future development on solar collectors.

S.A. Sulaiman

2013-01-01

359

An improved thermal and electrical model for a solar photovoltaic thermal (PV/T) air collector  

International Nuclear Information System (INIS)

In this paper, an attempt is made to investigate the thermal and electrical performance of a solar photovoltaic thermal (PV/T) air collector. A detailed thermal and electrical model is developed to calculate the thermal and electrical parameters of a typical PV/T air collector. The thermal and electrical parameters of a PV/T air collector include solar cell temperature, back surface temperature, outlet air temperature, open-circuit voltage, short-circuit current, maximum power point voltage, maximum power point current, etc. Some corrections are done on heat loss coefficients in order to improve the thermal model of a PV/T air collector. A better electrical model is used to increase the calculations precision of PV/T air collector electrical parameters. Unlike the conventional electrical models used in the previous literature, the electrical model presented in this paper can estimate the electrical parameters of a PV/T air collector such as open-circuit voltage, short-circuit current, maximum power point voltage, and maximum power point current. Further, an analytical expression for the overall energy efficiency of a PV/T air collector is derived in terms of thermal, electrical, design and climatic parameters. A computer simulation program is developed in order to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. Since some corrections have been down on thermal and electrical models, it is observed that the thermal and electrical simulation results obtained in this paper is more precise than the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency and overall energy efficiency of PV/T air collector is about 17.18%, 10.01% and 45%, respectively, for a sample climatic, operating and design parameters.

2010-07-01

360

Evaluation of Test Method for Solar Collector Efficiency  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2012-01-01

 
 
 
 
361

Comparação dos métodos de Atenuação de Energia Radiante e Titulométrico para a determinação de Etanol no sangue - DOI: 10.4025/actascihealthsci.v25i2.2165 A comparison of Radiative Energy Attenuation and Titrimetric methods for the analysis of ethanol in blood - DOI: 10.4025/actascihealthsci.v25i2.2165  

Directory of Open Access Journals (Sweden)

Full Text Available A determinação de álcool no sangue foi avaliada através da comparação de duas técnicas analíticas, o método de atenuação de energia radiante (AER e o método titulométrico (TIT. A sensibilidade do AER foi de 0,4g/L e por TIT de 0,1g/L. A curva padrão de etanol foi linear até 2,5g/L e 4,0g/L para os métodos AER e TIT, respectivamente. O coeficiente de variação intra-série foi de 1,5% a 3,9% e de 0,6% a 3,2%, sendo que o coeficiente de variação inter-série foi de 2,5% a 12,8% e de 0% a 3,3% para os métodos AER e TIT, respectivamente. Os testes de recuperação apresentaram os seguintes resultados, 105% para o método AER e 88% para o método TIT. Em 70 amostras estudadas, o coeficiente de correlação (r foi de 0,9681 e o resultado do teste-t de Student foi de -1,294, demonstrando que os métodos se correlacionam bem.The alcohol determination in the blood was evaluated through the comparison of two analytical techniques, the method of radiative energy attenuation (REA and the chemical titration method (TIT. The sensibility of REA was 0.4g/L and of TIT was 0.1g/L. The curve standard of etanol was linear up to 2.5g/L and 4.0g/L for methods REA and TIT, respectively. The coefficient of variation was 1.5% to 3.9% and 0.6% to 3.2% in the same day, and day-to-day coefficient of variation was 2.5% to 12.8% and 0% to 3.3% for methods REA and TIT, respectively. The tests of recovery presented the following results, 105% for REA and 88% for TIT. In 70 studied samples, the coefficient of correlation (r was 0,9681 and the result of the test-t of Student was -1,294.

Miguel Machinski Junior

2003-04-01

362

Solar Technology: Evacuated Tube Solar Collector  

Science.gov (United States)

This is a brief flash animation that provides an overview of the components in an Evacuated Tube Solar Collector. It also explains how these components maximize effectiveness of this type of solar collector as well as some advantages and disadvantages to this design. Note: this video may be slow to load when viewing for the first time.

2012-10-16

363

Improvements to flat plate solar collectors  

Energy Technology Data Exchange (ETDEWEB)

Designs of flat plate collectors with very low heat losses (when compared with conventional collectors) are described. One method reduces radiation losses by means of utilizing selective coatings. A second method reduces radiation and convection by means of a honeycomb structure in the space between the absorber and the cover glass. (MCW)

Loefving, S.

1982-01-01

364

Development and testing of the Shenandoah collector  

Science.gov (United States)

The test and development of the 7-meter Shenandoah parabolic dish collector incorporating an FEK-244 film reflective surface and cavity receiver are described. Four prototypes tested in the midtemperature Solar System Test Facility indicate, with changes incorporated from these development tests, that the improvements should lead to predicted performance levels in the production collectors.

Kinoshita, G. S.

1981-05-01

365

Comparative Study on Solar Collector’s Configuration for an Ejector-Refrigeration Cycle  

Directory of Open Access Journals (Sweden)

Full Text Available Solar collector’s configuration plays important role on solar-powered refrigeration systems to work as heat source for generator. Three types of solar collector consisting of flat plate, evacuated tube, and compound parabolic solar collectors are compared to investigate their performances. The performances consist of the behavior of heat which can be absorbed by the collectors, heat loss from the collectors and outlet temperature of working fluid at several slopes of the solar collectors. The new accurate analysis method of heat transfer is conducted to predict the performance of the solar collectors. The analysis is based on several assumptions, i.e. sky condition at Bandung is clear and not raining from 08.00 until 17.00 and thermal resistance at cover and absorber plate is negligible. The numerical calculation results confirm that performance of the evacuated tubes solar collector at the same operating conditions is higher than the others. For the case of an evacuated-tubes solar collector system with aperture area of 3.5 m2, the maximum heat which can be absorbed is 3992 W for the highest solar intensity of 970 W/m2 at 12.00 and horizontal position of the solar collector. At this condition, the highest outlet temperature of water is 347.15 K with mass flow rate 0.02 kg/s and inlet temperature 298 K.

Raffles Senjaya

2008-05-01

366

In situ built-up air collector with glass cover  

DEFF Research Database (Denmark)

In the first part of the project background information was gathered describing different jointing methods and materials that can be used for glass joints. In the light hereof indoor tests with different methods of jointing between glass were carried out. From this information a test box was built 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 was placed outdoors on a 45° tilted angled south-facing plate so that the joints were exposed to real weather conditions. At regular intervals the joints were inspected. After about 3-5 months 2 possibly suitable joints were selected to form part of two prototypes,one of which is a newly developed jointing profile. The prototypes were built in the test area of Department of Buildings and Energy. One of the prototypes has the airflow behind the absorber, which is an aluminium plate painted black, whereas the other has the airflow in front of the absorber. Here the black top side of the insulation acts 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 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,

Kristiansen, Finn Harken; Engelmark, Jesper

1998-01-01

367

Finite-elements modeling of radiant heat transfers between mobile surfaces; Modelisation par elements finis de transferts radiatifs entre surfaces mobiles  

Energy Technology Data Exchange (ETDEWEB)

In the numerical modeling of thermal industrial problems, radiant heat transfers remain difficult to take into account and require important computer memory and long computing time. These difficulties are enhanced when radiant heat transfers are coupled with finite-elements diffusive heat transfers because finite-elements architecture is complex and requires a lot of memory. In the case of radiant heat transfers along mobile boundaries, the methods must be optimized. The model described in this paper concerns the radiant heat transfers between diffuse grey surfaces. These transfers are coupled with conduction transfers in the limits of the diffusive opaque domain. 2-D and 3-D geometries are analyzed and two configurations of mobile boundaries are considered. In the first configuration, the boundary follows the deformation of the mesh, while in the second, the boundary moves along the fixed mesh. Matter displacement is taken into account in the term of transport of the energy equation, and an appropriate variation of the thermophysical properties of the transition elements between the opaque and transparent media is used. After a description of the introduction of radiative limit conditions in a finite-elements thermal model, the original methods used to optimize calculation time are explained. Two examples of application illustrate the approach used. The first concerns the modeling of radiant heat transfers between fuel rods during a reactor cooling accident, and the second concerns the study of heat transfers inside the air-gap of an electric motor. The method of identification of the mobile surface on the fixed mesh is described. (J.S.) 12 refs.

Daurelle, J.V.; Cadene, V.; Occelli, R. [Universite de Provence, 13 - Marseille (France)

1996-12-31

368

Radiant energy absorption enhancement in optical imaging systems  

Science.gov (United States)

Reimaging system efficiently uses incident light and overcomes previous imaging detector problems. Optical system collects reflected and focal plane transmitted light and redirects it so it again impinges on focal plane in register with original image. Reimaging unabsorbed light increases light absorption and detector use probability.

Brown, R. M.; Gunter, W. D., Jr.

1971-01-01

369

Camera system with array of radiant energy detectors  

International Nuclear Information System (INIS)

A gamma camera has an array of photodetectors arranged to produce a current pulse in response to a flash light produced by a scintillator in response to an incident gamma ray photon. Said current pulse is passed to an integrator which produces a voltage which rises from an initial reference level, to a peak level, said peak level being representative of the charge in the current pulse. The output of the integrator is reset by a circuit to the initial reference level a predetermined time after the production of the current pulse, thereby enabling each integrator to respond to the next current pulse produced by succeeding gamma ray photons. (author)

1980-12-29

370

Combination roof structure and solar collector  

Energy Technology Data Exchange (ETDEWEB)

A combination roof structure and solar collector is described for a building having vertical side walls and end walls. A plurality of laterally spaced trusses or bar joists extend from one wall to an opposite wall. A translucent panel is carried on top of the upper members which form part of the truss providing a roof surface for the building while permitting solar energy to pass therethrough. Panels are attached to elongated lower members forming part of the truss so as to define a chamber between the upper members of the truss and the panels. A solar energy absorbing surface is carried above the panels attached to the lower members. Insulation is provided between the solar energy absorbing surface and the interior of the building for insulating the interior of the building from the chamber. Air is circulated through the chamber for absorbing heat from the solar energy absorbing surface and the heated air is supplied to the interior of the building or to a rock storage.

Granger, F.R.

1980-12-16

371

Temperature dependent capacity contribution of thermally treated anode current collectors in lithium ion batteries  

International Nuclear Information System (INIS)

Highlights: ? We studied the influence of the thermal treatment of current collectors on the energy capacity. ? Different current collectors show different thermal treatment effect on performance. ? The non-negligible capacity contribution is closely related to the treatment temperatures. ? Our results could be beneficial to designing battery architectures. - Abstract: Metal current collectors, offering a good connection between the active materials and the external circuit, is an important component in a rechargeable lithium ion battery. Some necessary thermal treatment in the battery fabrication and assembly procedure results in current collectors with some non-negligible reversible energy capacities; however, these energy capacities were negligible in the previous references. In this research, for the first time, we investigated the influence of the thermal treatment of current collectors (such as copper foil and stainless steel disk) on energy capacities. Our results indicate that different current collector materials have different thermal treatment effects on their electrochemical performance. The non-negligible capacity contribution is closely related to the treatment temperature.

2013-01-01

372

Solar Thermal Systems Performances versus Flat Plate Solar Collectors Connected in Series  

Directory of Open Access Journals (Sweden)

Full Text Available This paper shows the modeling of a solar collective heating system in order to predict the system performances. Two systems are proposed: 1 the first, Solar Direct Hot Water, which is composed of flat plate collectors and thermal storage tank, 2 the second, a Solar Indirect Hot Water in which we added an external heat exchanger of constant effectiveness to the first system. The mass flow rate by a collector is fixed to 0.04 Kg?s–1 and the total number of collectors is adjusted to 60. For the first system, the maximum average water temperature within the tank in a typical day in summer and annual performances are calculated by varying the number of collectors connected in series. For the second, this paper shows the detailed analysis of water temperature within the storage and annual performances by varying the mass flow rate on the cold side of the heat exchanger and the number of collectors in series on the hot side. It is shown that the stratification within the storage is strongly influenced by mass flow rate and the connections between collectors. It is also demonstrated that the number of collectors that can be connected in series is limited. The optimization of the mass flow rate on cold side of the heat exchanger is seen to be an important factor for the energy saving.

Khaled Zelzouli

2012-12-01

373

Shape control of solar collectors using torsional shape memory alloy actuators  

Energy Technology Data Exchange (ETDEWEB)

Solar collectors that are focused on a central receiver are designed with a mechanism for defocusing the collector or disabling it by turning it out of the path of the sun`s rays. This is required to avoid damaging the receiver during periods of inoperability. In either of these two cases a fail-safe operation is very desirable where during power outages the collector passively goes to its defocused or deactivated state. This paper will be principally concerned with focusing and defocusing the collector in a fail-safe manner using shape memory alloy actuators. Shape memory alloys are well suited to this application in that once calibrated the actuators can be operated in an on/off mode using a small amount of electric power. Also, in contrast to other smart materials that were investigated for this application, shape memory alloys are capable of providing enough stroke at the appropriate force levels to focus the collector. In order to accommodate the large, nonlinear deformations required in the solar collector plate to obtain desired focal lengths, a torsional shape memory alloy actuator was developed that produces a stroke of 0.5 inches. Design and analysis details presented, along with comparisons to test data taken from an actual prototype, demonstrate that the collector can be repeatedly focused and defocused within accuracies required by typical solar energy systems.

Lobitz, D.W.; Rice, T.M.; Grossman, J.W. [and others

1996-03-01

374

Development of a Solar Assisted Drying System Using Double-Pass Solar Collector with Finned Absorber  

International Nuclear Information System (INIS)

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%.

2012-09-18

375

Performance of solar collectors under low temperature conditions : Measurements and simulations results  

DEFF Research Database (Denmark)

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 evaluated and results compared to experimental measurements. A mathematical model is also under development to include, in addition to the condensation phenomena, the frost, the rain and the long-wave radiation gains/losses on the rear of the solar collector. While the potential gain from rain was estimated to be around 2%, frost heat gains were measured to be up to 40% per day, under specific conditions. Overall, results have shown that unglazed collectors are more efficient than flat plate or evacuated tube collectors at low operation temperatures or for night conditions, making them more suitable for heat pump applications.

Bunea, Mircea; Eicher, Sara

376

Development of a Solar Assisted Drying System Using Double-Pass Solar Collector with Finned Absorber  

Science.gov (United States)

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%.

Azmi, M. S. M.; Othman, M. Y.; Sopian, K.; Ruslan, M. H.; Majid, Z. A. A.; Fudholi, A.; Yasin, J. M.

2012-09-01

377

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

Directory of Open Access Journals (Sweden)

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

Madhukeshwara. N, E. S. Prakash

2012-01-01

378

Grid Collector: Using an event catalog to speed up user analysisin distributed environment  

Energy Technology Data Exchange (ETDEWEB)

Nuclear and High Energy Physics experiments such as STAR at BNL are generating millions of files with Peta Bytes of data each year. In most cases, analysis programs have to read all events in a file in order to find the interesting ones. Since the interesting events may be a small fraction of events in the file, a significant portion of the computer time is wasted on reading the unwanted events. To address this issue, we developed a software system called Grid Collector. The core of Grid Collector is an Event Catalog. This catalog can be efficiently searched with compressed bitmap indices. Tests show that Grid Collector can index and search STAR event data much faster than database systems. It is fully integrated with an existing analysis framework so that a minimal effort is required to use Grid Collector. In addition, by taking advantage of existing file catalogs, Storage Resource Managers (SRMs) and GridFTP, Grid Collector automatically downloads the needed files anywhere on the Grid without user intervention. Grid Collector can significantly improve user productivity. For a user that typically performs computation on 50 percent of the events, using Grid Collector could reduce the turn around time by 30 percent. The improvement is more significant when searching for rare events, because only a small number of events with appropriate properties are read into memory and the necessary files are automatically located and down loaded through the best available route.

Wu, Kesheng; Shoshani, Arie; Zhang, Wei-Ming; Lauret, Jerome; Perevoztchikov, Victor

2004-11-01

379

Numerical and experimental analysis of a point focus solar collector using high concentration imaging PMMA Fresnel lens  

International Nuclear Information System (INIS)

Research highlights: ? We studied a point focus Fresnel solar collector using different cavity receivers. ? The collector heat removal factors are derived to find the optimal cavity shape. ? Numerical and experimental analysis shows that the conical cavity is optimum. -- Abstract: A high concentration imaging Fresnel solar collector provided with different cavity receivers was developed and its behavior was investigated. Round copper pipes winded into different spring shapes were used as receiver by placing in the cylindrical cavity to absorb concentrated solar energy and transfer it to a heat transfer fluid (HTF). The collector efficiency factor and collector heat removal factor were derived for the cavity receivers to find out heat transfer mechanism and to propose an effective way for evaluating the performance of Fresnel solar collector and determining the optimal cavity structure. The problem of Fresnel solar collector with synthetic heat transfer oil flow was simulated and analyzed to investigate heat loss from different cavity receivers. Solar irradiation as well as convection and heat transfer in the circulating fluid and between the internal surfaces of the cavity and the environment are considered in the model. The temperature distribution over its area as well as the collector thermal efficiency at nominal flow rate was used in order to validate the simulation results. It was found that the simulated temperature distribution during operation and the average collector efficiency are in good agreement with the experimental data. Finally, the optimal shape of solar cavity receiver, as well as its thermal performance, are deeply analyzed and discussed.

2011-06-01

380

A finite-volume model of a parabolic trough photovoltaic/thermal collector: Energetic and exergetic analyses  

International Nuclear Information System (INIS)

This paper presents a detailed finite-volume model of a concentrating photovoltaic/thermal (PVT) solar collector. The PVT solar collector consists in a parabolic trough concentrator and a linear triangular receiver. The bottom surfaces of the triangular receiver are equipped with triple-junction cells whereas the top surface is covered by an absorbing surface. The cooling fluid (water) flows inside a channel along the longitudinal direction of the PVT collector. The system was discretized along its axis and, for each slice of the discretized computational domain, mass and energy balances were considered. The model allows one to evaluate both thermodynamic and electrical parameters along the axis of the PVT collector. Then, for each slice of the computational domain, exergy balances were also considered in order to evaluate the corresponding exergy destruction rate and exergetic efficiency. Therefore, the model also calculates the magnitude of the irreversibilities inside the collector and it allows one to detect where these irreversibilities occur. A sensitivity analysis is also performed with the scope to evaluate the effect of the variation of the main design/environmental parameters on the energetic and exergetic performance of the PVT collector. -- Highlights: ? The paper investigates an innovative concentrating photovoltaic thermal solar collector. ? The collector is equipped with triple-junction photovoltaic layers. ? A local exergetic analysis is performed in order to detect sources of irreversibilities. ? Irreversibilities are mainly due to the heat transfer between sun and PVT collector.

2012-10-01

 
 
 
 
381

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)

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.)

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

382

Modeling Spatio-Temporal Dynamics of Optimum Tilt Angles for Solar Collectors in Turkey  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Quantifying spatial and temporal variations in optimal tilt angle of a solar collector relative to a horizontal position assists in maximizing its performance for energy collection depending on changes in time and space. In this study, optimal tilt angles were quantified for solar collectors based on the monthly global and diffuse solar radiation on a horizontal surface across Turkey. The dataset of monthly average daily global solar radiation was obtained from 158 places, and monthly diffuse...

2008-01-01

383

Investigation of Hydraulic and Thermal Performance of Solar Collectors used for Solar Cooling  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Solar cooling is an emerging technology and in a process of development to be competitive with the conventional systems generally based on electricity driven vapor compression cooling machines. Efficient performance of the solar collectors consistently over a time span of 20-25 years is the key towards achieving the required primary energy savings and cost benefits. The present research work investigates various thermal and hydraulic aspects of the solar collectors used for a solar cooling ap...

Badar, Abdul Waheed

2012-01-01

384

Analytical predictions of liquid and air photovoltaic/thermal flat-plate collector performance  

Energy Technology Data Exchange (ETDEWEB)

Two separate one-dimensional analyses have been developed for the prediction of the thermal and electrical performance of both liquid and air flat-plate photovoltaic/thermal (PV/T) collectors. The analyses account for the temperature difference between the primary insolation absorber (the photovoltaic cells) and the secondary absorber (a thermal absorber flat plate). The results of the analyses are compared with test measurements, and therefrom, design recommendations are made to maximize the total energy extracted from the collectors.

Raghuraman, P.; Hendrie, S.D.

1980-01-01

385

Numerical modelling of a parabolic trough solar collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Concentrated Solar Power (CSP) technologies are gaining increasing interest in electricity generation due to the good potential for scaling up renewable energy at the utility level. Parabolic trough solar collector (PTC) is economically the most proven and advanced of the various CSP technologies. The modelling of these devices is a key aspect in the improvement of their design and performances which can represent a considerable increase of the overall efficiency of solar power plants. In the...

Hachicha, Ahmed Amine

2013-01-01

386

Development of a non-premixed radiant burner. Experimental results  

Energy Technology Data Exchange (ETDEWEB)

The objective was to develop and test a non-premixed radiant burner. A burner concept, pro-type 1, was developed with special attention to minimise emissions and foam peak-temperatures. During the test of the prototype it became evident that the construction was not feasible, because the ceramic gas distribution tubes eventually were blocked by soot. Experiments to investigate if the gas would crack conducted prior to the construction of the burner did not indicate that any problems would occur. It can therefore be concluded that the experiments did not simulate burner conditions adequately. Alternative prototypes in which the gas is not heated prior to injection into the combustion chamber have been established. The concept operated satisfactorily without preheating of the combustion air, although NO{sub x}-emissions were high. The measured process efficiencies were superior to previous results for different kinds of surface burners. When the combustion air was preheated to 400 deg. C, the foam sections broke down. The experimental results can be summarised in the following conclusions: The developed prototypes can not be operated with combustion air preheated to 400 deg. C or higher; A relative improvement of the process efficiency by 22% has been observed when the combustion air is preheated to 400 deg. C; The NO{sub x}-emissions increase significantly and much more than the process efficiency when the combustion air is preheated; The process efficiency obtained with prototype 5 is better than previously investigated surface burners, especially at high loads. Possible means to improve durability, efficiency and emission level for both burner concepts are suggested. These include cooling of the gas in prototype 1, coating of the downstream side of the foam section to improve the radiant efficiency and multistep combustion. (EHS)

Andersen, P.; Myken, A.N.; Rasmussen, N.B.

1997-12-31

387

26 CFR 1.48-9 - Definition of energy property.  

Science.gov (United States)

...water heater, include a roof solar collector, a heat exchanger, a hot...basement through pipes to the roof solar collector. Heated water returns through...the building. (f) The roof solar collector is solar energy property....

2010-04-01

388

26 CFR 1.48-9 - Definition of energy property.  

Science.gov (United States)

...include a roof solar collector, a heat exchanger...through pipes to the roof solar collector. Heated water returns...water tank. (e) An integrated control component... (f) The roof solar collector is solar energy...

2010-04-01

389

Combined solar heater and collector  

Energy Technology Data Exchange (ETDEWEB)

A combined solar collector and storage device comprises a housing including a plurality of wire mesh racks for retaining and storing rock therein and also including a front face formed of mesh allowing solar radiation to impinge on the rock and penetrate deeply into the housing. A plurality of intersecting tunnels being formed of mesh include a plurality of sunlight entry tunnels and inner chamber tunnels wherein the inner chamber tunnels intersect the sunlight entry tunnels at closely spaced intervals so that solar radiation may be directed toward rock in the interior of the housing. The housing also includes a frame, a plurality of side walls and a base, which cooperate with the front face to retain the rock within the housing.

Wille, F.P.

1984-09-18

390

Experimental Comparison of Two Configurations of Hybrid Photovoltaic Thermal Collectors  

International Nuclear Information System (INIS)

The combination of a thermal collector and a photovoltaic module in a single system allows for increased efficiency of the total conversion of solar energy. A synergistic effect can be obtained in a structure combining these two devices in a judicious manner to those of thermal and photovoltaic system installed separately. Production of total energy from hybrid collector depends on the input (that is to say, the. energy of solar radiation, air temperature and wind speed) and output which is the electric production and the temperature of the system. Thin production also depends on the mode of heal extraction. In this paper, an experimental Study of two configurations of hybrid collectors is described. The configuration that the absorber is made by galvanized steel and in the second, the absorber is a copper serpentine. The advantages of the first configuration are mainly due to low cost and simplicity but the second configuration has the advantage of promoting the heat transfer between cells and fluid. (authors)

2011-01-01

391

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

International Nuclear Information System (INIS)

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

2012-02-01

392

Thermal Efficiency of Double Pass Solar Collector with Longitudinal Fins Absorbers  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: One of the most important components of a solar energy system is the solar collector. The performances of double-pass solar collector with longitudinal fins absorbers are analyzed. Approach: The study involves a theoretical study to investigate the effect of mass flow rate, number and height of fins on efficiency, which involves steady-state energy balance equations on the longitudinal fins absorber of solar collectors. The theoretical solution procedure of the energy equations uses a matrix inversion method and making some algebraic rearrangements. Results: The collector efficiency increases as the number and height of fins increases. For a mass flow rate 0.02- 0.1kg/s, the double-pass solar collectors are efficiency about 36-73% in upper fins (type I, 37-75% in lower fins (type II and 46-74% in upper and lower fins (type III. Conclusion: The efficiency of the collector is strongly dependent on the flow rate, efficiency increase is about 35%.

Ahmad Fudholi

2011-01-01

393

Performance Evaluation of a Nanofluid (CuO-H2O) Based Low Flux Solar Collector  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As the fossil fuels are depleting continuously, we know that solar energy harvesting is a significant potential area for new research dimensions. Sun provides us about 1.9 x 108TWh/yr on the land, of which 1.3 x 105 TWh]/yr energy is used. In order to make much use of solar energy on the earth, solar energy harvesting into more usable form (e.g. heat or electricity) by using solar energy collectors is important aspect. A solar collector [1] is a device which transfers the collected solar ener...

2013-01-01

394

Human response to local convective and radiant cooling in a warm environment.  

DEFF Research Database (Denmark)

The response of 24 human subjects to local convective cooling, radiant cooling, and combined radiant and convective cooling was studied at 28°C and 50% relative humidity. The local cooling devices used were (1) a tabletop cooling fan, (2) personalized ventilation providing a stream of clean air, (3) radiant panels below and above the desk in front of the desk occupant, and (4) the same two radiant panels but with small fans blowing room air toward the upper panel to be cooled and redirected toward the person. A reference condition without cooling was also tested. The cooling devices significantly (p<0.05) improved subjectsâ?? thermal comfort compared to the condition without cooling. The acceptability of the thermal environment was similar for all cooling devices. The acceptability of air movement and perceived air quality increased when local cooling methods were used. The best results were achieved with personalized ventilation or the tabletop fan. Only minimal improvement in perceived air quality was reported when the radiant panel was used alone, indicating that in a warm environment, local convective cooling is superior to local radiant cooling as a means of improving perceived air quality. The intensity of the reported sick building syndrome symptoms increased during the exposure time, with or without cooling devices in operation. Air movement had very little effect on sick building syndrome symptoms, but they increased when the pollution level was high. The lowest prevalence of symptoms was reported with personalized ventilation and with the radiant panel with attached fans, which also caused subjects to report less fatigue. Sick building syndrome symptoms increased most when the tabletop fan, generating movement of polluted room air, was in operation. The temperature of the inhaled air rather than any local cooling of the head was associated with sick building syndrome symptoms, although this needs further study. The most preferred cooling method was personalized ventilation for six subjects, fan for eight subjects, and radiant panel (or radiant panel + fans) for nine subjects.

Melikov, Arsen Krikor; Krejcirikova, Barbora

2013-01-01

395

Analytical and experimental investigations into the performance of a double-pass photovoltaic thermal solar collector  

Science.gov (United States)

This study presents analytical and experimental investigations of a double-pass photovoltaic thermal solar air collector. Photovoltaic thermal collector is a combination of thermal and photovoltaic systems. It generates both thermal and electrical energies simultaneously. An experimental setup of a double-pass photovoltaic thermal solar air collector was designed and fabricated to study the performance over a range of design and operating conditions. A set of steady-state energy balance equations was formulated for the two air streams, the glass cover, the photovoltaic panel, and the back-plate. These equations were reduced to a set of two differential equations, and a closed-form solution was obtained. Reasonably close agreements between the analytical and experimental results were obtained. This model was used to simulate the performance of larger double-pass photovoltaic thermal system by varying the photovoltaic length, packing factor, air mass flow rate and channel depth. The minimum area of the photovoltaic cell necessary to generate sufficient electrical energy to run the fan at a given mass flow rate was also calculated as a function of time for different configurations of the collector. Several important relationships between the design and operating conditions were obtained. These relationships affected the performance of the double-pass photovoltaic thermal solar collector. Hence, design curves for the photovoltaic thermal solar collector were developed. The designer would be able to predict the performance of the system using the design curves by selecting the required conditions. This includes the effects of changing the channel depth and air mass flow rate on the global solar radiation, thermal, photovoltaic and combined thermal photovoltaic efficiencies, and temperature rise of the collector. An economic optimization model was developed to study the effect of combinations of mass flow rates, photovoltaic panel length and channel depth on the cost-benefit ratio of the collector. The user could select the optimum design features that correspond to minimum cost-benefit ratio.

Sopian, Kamaruzzaman Bin

396

Mechanism for transformation of terrigenous pore collectors  

Energy Technology Data Exchange (ETDEWEB)

Results are examined of mutual influence of rocks and fluids and the transformation of terrigenous pore collectors into fractured in the process of submersion of rocks. Three stages of submersion are isolated with corresponding types of collectors: initial (immigration), main (redistribution of fluids in collectors and generation of fractures of natural hydraulic rupture) and critical (separation of the fluids from a pore space into the fractured reservoir). Examples are presented of the mutual influence of rocks and fluids, and the results of reformation of deposits during their submersion in the interval 1500-5000 m.

Lyakhovich, L.K.

1980-01-01

397

CISBAT 2007 - Solar collectors (heat and electricity)  

International Nuclear Information System (INIS)

This is the third part of the proceedings of the 2007 CISBAT conference on Renewables in a changing climate, held in Lausanne, Switzerland. On the subject of Building and urban integration of renewables the following oral contributions are summarised: 'Facade integration of solar thermal collectors: present and future', 'Long term experiences with a versatile PV in roof system', 'Development of a design and performance prediction tool for the ground source heat pump and underground thermal storage system', 'Hygrothermal performance of earth-to-air heat exchanger: long-term data evaluation and short-term simulation' as well as 'The real cost of heating your home: a comparative assessment of home energy systems with external costs'. Poster-sessions on the subject include 'Central solar heating plants with seasonal heat storage', 'Analysis of forced convection for evaporative air flow and heat transfer in PV cooling channels', 'Renewable energy technology in Mali: constraints and options for a sustainable development', 'Effect of duct width in ducted photovoltaic facades', 'Design and actual measurement of a ground source heat pump system using steel foundation piles as ground heat exchangers', 'Development of an integrated water-water heat pump unit for low energy house and its application', 'PV effect in multilayer cells and blending of fullerene/poly (3-hexylthiophene) and phthalocyanine having NIR charge transfer absorption band', 'CdTe photovoltaic systems - an alternative energetic', 'Integration of renewable energy sources in a town, examples in Grenoble', 'A prospective analysis method for the conception of solar integration solutions in buildings' and 'Energy and aesthetic improvements for building integration of cost effective solar energy systems'. Further groups of presentations at the conference are reported on in separate database records. An index of authors completes the proceedings

2007-09-04

398

Transient performance analysis of cylindrical parabolic concentrating collectors and comparison with experimental results  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the unsteady, one-dimensional performance analysis of cylindrical parabolic concentrating collectors through the first and second laws of thermodynamics. These laws, together, help to define the optimum system that satisfies the imposed thermal and economical constraints and minimizes exergy loss. The analysis considers the thermal masses of the absorber pipe, pyrex envelope and the working fluid of the system individually, in an unsteady state. The instantaneous exergetic and energy efficiencies for the cylindrical parabolic collectors are compared for daily insolation at different flow rates. The values measured using the MKE Institute Collector Test Facility are in good agreement with the predicted simulation results. The simulation results indicate that the exergetic efficiency is highly dependent on the mass flow rates and the arrangement of the cylindrical parabolic collector array. The optimum flow rates which provide minimum exergy loss were obtained from the simulation model. (author)

Eskin, N. [Istanbul Technical University (Turkey). Faculty of Mechanical Engineering

1999-10-01

399

Effects of a collector work function and emission on converter performance  

International Nuclear Information System (INIS)

The effect of the characteristics of a thermionic converter collector, such as electron emission, work function and surface inhomogeneity, on the voltage drop in the gap and plasma parametrs is investigated in a general form. As a result of reduction of eight equatins in eleven unknowns being a part of collector boundary conditions, to one equation in four unknowns and the analysis of this equation the definite relation between plasma electron temperature and its other derivatives near the collctors is obtained. On the basis of the energy balance equation for electrons and the assumption on independence of plasma parameters on the collector emission the expression for optimum emission value at which useful voltage reaches its maximum is derived. The optimum emission depends on both the characters of work function variation with temperature and the degree of the collectors work function homogeneity

1986-04-01

400

Thermal performance testing and mathematically modeling of integral collector storage solar hot water systems  

Science.gov (United States)

The concept behind the alternative testing method is to characterize the thermal performance of the solar collection elements in the integral system using standard test methods for conventional solar collectors. After measuring the efficiency and incident angle response, the integral collector storage hot water system would be tested using an electrical heat source to simulate the absorbed solar energy. The research included both experimental and analytical investigations on the collector elements and on the complete system. All day tests were performed on two commercial integral collector storage solar domestic hot water systems. Tests were performed under a variety of ambient conditions and irradiance levels. An analytical model was developed to predict the thermal performance of one of the systems. Predicted performance was compared with experimental results.

Thomas, W. C.

1985-02-01

 
 
 
 
401

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

International Nuclear Information System (INIS)

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.

2013-06-17

402

Setting priorities - reducing the cost of a gas radiant heating system by means of target heat control. Prioritaeten setzen - Verringern der Kosten einer Gasstrahlungsheizung mit Zielwaermesteuerung  

Energy Technology Data Exchange (ETDEWEB)

A large part of the running costs of gas radiant heating is caused by the socalled preparation or service price. In order to reduce these costs, a target heat control with microprocessor technique has been developed. With this it is possible to switch groups of radiators according to priorities. The maximum heat energy can therefore be reduced overall, which can lead to cost savings of the order of up to 30 percent. (orig.).

Weinmann, R.

1988-01-01

403

Experimentation of a Plane Solar Integrated Collector Storage Water Heater  

Directory of Open Access Journals (Sweden)

Full Text Available In order to popularize the use of the solar-water heaters, especially in the residential and tertiary sectors with the third world, it appears to be necessary to reduce their cost while improving their performances. It is the object of this integrated storage collector thus created and tested in the south of Tunisia. It is simply made up of a tank playing the double part of solar absorber and storage tank of warm water, of a glazing to profit from the greenhouse effect and of an insulating case. Its measured energy performances, by the method of input-output proves its effectiveness to produce hot water, in spite of its simplicity of manufacture, usage and maintenance. Indeed a temperature of water exceeding 70?C is reached towards the afternoon True Solar Time, and for an efficiency of 7%. Thus, this type of collector with integrated storage is entirely satisfactory and could be available to larger mass.

Romdhane Ben Slama

2012-03-01

404

Exergetic performance assessment of a solar photovoltaic thermal (PV/T) air collector  

Energy Technology Data Exchange (ETDEWEB)

In this paper, an attempt is made to evaluate the exergetic performance of a solar photovoltaic thermal (PV/T) air collector. A detailed energy and exergy analysis is carried out to calculate the thermal and electrical parameters, exergy components and exergy efficiency of a typical PV/T air collector. Some corrections are done on related heat loss coefficients. An improved electrical model is used to estimate the electrical parameters of a PV/T air collector. Further, a modified equation for the exergy efficiency of a PV/T air collector is derived in terms of design and climatic parameters. A computer simulation program is also developed to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. It is observed that the modified exergy efficiency obtained in this paper is in good agreement with the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency, overall energy efficiency and exergy efficiency of PV/T air collector is about 17.18%, 10.01%, 45% and 10.75% respectively for a sample climatic, operating and design parameters. (author)

Sarhaddi, F.; Farahat, S.; Ajam, H.; Behzadmehr, A. [Department of Mechanical Engineering, Shahid Nikbakht Faculty of Engineering, University of Sistan and Baluchestan, Zahedan 98164-161 (Iran, Islamic Republic of)

2010-11-15

405

Technical and economical assessment of integrated collector storage solar water heaters  

International Nuclear Information System (INIS)

Solar water heating implementation has as effect greenhouse gas emission reduction. Romanian solar collector market and solar technologies implementation are not yet developed because the market is dominated by high cost equipment. Due to this, the author deduces that the use of simpler technologies, with lower technical performances, but inferior capital cost, will induce higher solar energy penetration into the market. One of the cheapest solutions for solar water heating is Integrated Collector Storage Solar Water Heaters technology. The author purpose an analytical method for technical and economical solar collector's performance assessment. Technical performances of the solar collectors will be compared for different types of ICSSWH's. Systems calculation will be done analytically. The starting point of the estimation is the heat balance on solar collector's boundary. Using heat transfer equation, energy fluxes and equipment efficiencies during collection and store time can be calculated. Technical performances for market existing solar collectors will be reminded. The paper conclusions are valuable for solar hot water design. (author)

2007-11-22

406

Maximization od solar energy per square meter by means of PVT (Photovoltaic thermal hybrid solar collectors). Sustainable heating system for Rijksgebouwendienst Zoetermeer, Netherlands; Maximalisering zonne-energie per vierkante meter met PVT. Duurzaam verwarmingssysteem Rijksgebouwendienst Zoetermeer  

Energy Technology Data Exchange (ETDEWEB)

An office building of the Dutch Government Buildings Agency (RGD) in Zoetermeer, Netherlands, is monitored to determine the feasibility of PVT (Photovoltaic thermal hybrid solar collectors) panels. The PVT system is connected to the hot tap water system. The aim is to be able to calculate reliable yields and to test the applicability for the Netherlands [Dutch] Een kantoorgebouw van de Rijksgebouwendienst in Zoetermeer is gemonitord om de haalbaarheid van PVT-panelen (fotovoltaische thermische hybride zonnecollectoren) te bepalen. Het PVT-systeem is aangesloten op het warmtapwaterysteem. Het doel is betrouwbare opbrengsten te kunnen berekenen en de toepasbaarheid voor Nederland te testen.

Van Helden, W. [Renewable Heat, Schagen (Netherlands); Roossien, B. [EnergyGO, Den Helder (Netherlands); Mimpen, J. [Rijksgebouwendienst, Zoetermeer (Netherlands)

2013-02-15

407

Solar collectors versus lamps - a comparison of the energy demand of industrial photochemical processes as exemplified by the production of {epsilon}-caprolactam  

Energy Technology Data Exchange (ETDEWEB)

The energy demand of photochemical synthesis of {epsilon}-caprolactam was compared for two plant concepts. The conventional lamp-driven concept followed the process as realized on an industrial scale by Toray Ltd, Japan and a solar concept was designed at identical yearly output. The aim of the comparison was to determine the savings of fossil fuels that could be achieved if photochemistry could make use of solar radiation instead of artificial light. The use of solar radiation for the photochemical production of {epsilon}-caprolactam has a 4-fold lower demand for electric current and an 8-fold lower demand for cooling energy as compared to an equivalent conventionally operated route. Furthermore, due to avoided conversion of fossil fuel to electric current, a solar process would allow specific emissions of 1.5-2.5 tons of CO{sub 2} per ton {epsilon}-caprolactam to be avoided, depending on the primary energy carrier used. (author)

Funken, K.-H.; Mueller, F.-J.; Ortner, J.; Riffelmann, K.-J.; Sattler, C. [Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Koeln (Germany). Solare Energietechnik

1999-08-01

408

Energy savings in dust collector plants of bag house filter type. Phase 1 - Literature study; Energieffektivisering av anlaeggningar foer stoftrening med slangfilter. Etapp 1-Litteraturstudie  

Energy Technology Data Exchange (ETDEWEB)

The largest energy demands in connection with the operation of bag house filters are the electric energy consumption for the fans, securing the flow of flue gas through the filter, and the electric energy consumption when producing the pressurized air (compressors or high pressure fans). Considering the significantly increased fan work when having a non-optimised cleaning of the filters, it seems justified to investigate the possibilities to minimise the unnecessary pressure drop. There is also a saving potential in the filter cleaning process, which otherwise may cost an unacceptable amount of pressurized air or other energy. The main purpose of this work is to develop methods to optimize the operation of bag house filters, which is started up with this report containing a follow-up of what has been done in Denmark and a confirmation of the technology status. In the next step, a case study where two-three plants are examined more in detail is suggested followed by a potential study to estimate the total energy saving potential in Sweden. Dust precipitation with bag house filters is basically a rather simple technique, which has existed in flue gas cleaning for about 50 years. From the literature study it can be established that there has been no revolutionary development in the field, but there are some work being done mainly to introduce new filter material but also to optimise the use of bag house filters with new computer based control systems. The largest potential of energy saving prevails if the filter from the beginning is overloaded, which usually is the case. The reason for overload may be a too large volume flow in relation to the filter area, that the dust has penetrated and blocked the filter, a defective filter cleaning process or that wrong filter material has been chosen. In Denmark a study has been made with the purpose to investigate the possibilities to optimise the energy consumption for bag house filters. For the three plants studied, an average energy saving of 50% was noted by exchange of filter material and improvement of the cleaning process. Other plants in Denmark have been rebuilt during the latest years but for these plants no reports have been found concerning how efficient the measures have been regarding energy demand for the filters. Today the suppliers of bag house filters have refined the control systems for the on-line cleaning of the filters. The systems differs in advance but are usually based on minimising the pressure drop on the flue gas side by keeping the dust layer thickness on the filter constant on the smallest possible level considering the flue gas dust emission. Very often this is combined with minimising the energy consumption of the cleaning process. Also the consumption of chemicals (for example limestone, active coal) are minimised by these control systems, which mainly in larger plants may be prior to minimising the electric energy consumption.

Eriksson, Lars; Wikman, Karin; Berg, Magnus [AaF-Energi and Miljoe AB, Stockholm (Sweden)

2004-01-01

409

Role of collector alternating charged patches on transport of Cryptosporidium parvum oocyst in a patchwise charged heterogeneous micromodel  

Energy Technology Data Exchange (ETDEWEB)

The role of collector surface charge heterogeneity on transport of Cryptosporidium parvum oocyst and carboxylate microsphere in 2-dimensional micromodels was studied. The cylindrical silica collectors within the micromodels were coated with 0, 10, 20, 50 and 100% Fe2O3 patches. The experimental values of average single collector removal efficiencies (?) of the Fe2O3 patches and on the entire collectors were determined. In the presence of significant (>3500 kT) Derjaguin–Landau–Verwey–Overbeek (DLVO) energy barrier between the microspheres and the silica collectors at pH 5.8 and 8.1, the values of ? determined for Fe2O3 patches were significantly less (p < 0.05, t-test) than that obtained for collectors coated entirely with Fe2O3. However, ? on Fe2O3 patches for microspheres at pH 4.4 and for oocysts at pH 5.8 and 8.1, where the DLVO energy barrier was relatively small (ca. 200-360 kT), were significantly greater (p < 0.05, t-test) than that on the collectors coated entirely with Fe2O3. The dependence of ? determined for Fe2O3 patches on the DLVO energy barrier indicated the importance of periodic favorable and unfavorable electrostatic interactions between colloids and collectors with alternating Fe2O3 and silica patches. Differences between experimentally determined ? and that predicted by a patchwise geochemical heterogeneous model was observed, but can be explained by the model’s lack of consideration for the spatial distribution of charge heterogeneity on the collector surface and colloid migration on patchwise heterogeneous collectors.

Liu, Yuanyuan; Zhang, Changyong; Hu, Dehong; Kuhlenschmidt, Mark S.; Kuhlenschmidt, Theresa B.; Mylon, Steven E.; Kong, Rong; Bhargava, Rohit; Nguyen, Thanh H.

2013-02-04

410