... Title : Solar Energy Absorption Efficiency of an Ellipsoidal Receiver-Reactor with Specularly Reflecting Walls. Descriptive Note : Technical rept. ...
DTIC Science & Technology
The Direct Absorption Receiver (DAR) concept was proposed in the mid 1970's as an alternative advanced receiver concept to simplify and decrease the cost of central receiver systems. Rather than flowing through tubes exposed to the concentrated solar flux...
National Technical Information Service (NTIS)
... 3. RECIPIENT'S CATALOG NUMBER TR- 12I 4. TITLE (and Subtitle) SOLAR ENERGY ABSORPTION s. TYPE OF REPORT & PERIOD COVERED ...
In a solar central receiver system Direct Absorption Receiver (DAR), the heat absorbing fluid (a blackened molten nitrate salt) flows in a thin film down a vertical panel (rather than through tubes as in conventional receiver designs) and absorbs the conc...
The direct absorption receiver (DAR) represents a fairly significant departure from conventional salt-in-tube receiver technology and appears to offer substantial promise for future generations of receivers. The DAR concept involves absorbing the solar fl...
Solar absorptance data on Pyromark painted receiver panels at the 10 MWe Solar Thermal Central Receiver Pilot Plant located near Barstow, California are reported. Measurements were made in 1982, 1983, and 1984. Selected measurements were made in 1985 afte...
The direct absorption receiver (DAR) concept offers the potential of high temperature operation by using concentrated solar energy. This paper examines the minimum flow rate and other relevant issues required to maintain a continuous film flowing over the absorption surface.
Energy Citations Database
The direct absorption receiver (DAR) concept offers the potential of high temperature operation by using concentrated solar energy. The minimum flow rate and other relevant issues required to maintain a continuous film flowing over the absorption surface are examined.
NASA Astrophysics Data System (ADS)
... for atmospheric absorptivities, scattering and reflectivity and cloud and earth surface reflectivity to compute the solar insolation received and ...
Recent solar central receiver designs emphasize direct absorption receiver (DAR) concepts primarily because of their ability to absorb high flux densities. An attractive design utilizes molten salt as the transport/storage fluid, which is pumped to the re...
A direct absorption receiver (DAR) concept offers the potential of significantly higher operating temperatures than current receiver designs. However, one of the concerns about the successful operation of DAR lies in the stability of a thin liquid-film fl...
Solar absorption characteristics are established for several films potentially favorable for use as receiving surfaces in solar energy collectors. Included in the investigation were chemically produced black films, black electrodeposits, and anodized coat...
A detailed numerical model is presented for the Catalytically Enhanced Solar Absorption Receiver (CAESAR). CAESAR is a high-temperature chemical reactor for the carbon dioxide reforming of methane. Concentrated solar energy is volumetrically absorbed thro...
faces (for cavity receivers) or exterior surfaces (for external receivers) to have the highest possible absorptivity in the solar band (a*). ...
NASA Website
The Direct Absorption Receiver (DAR) concept was proposed in the mid-1970s as an alternative advanced receiver concept to simplify and reduce the cost of solar central receiver systems. Rather than flowing through tubes exposed to the concentrated solar f...
This paper presents a test method for determining the thermal loss from a solar central receiver at normal operating conditions. The thermal loss determined by this test method is independent of knowing the incident solar power onto the receiver. Thermal loss includes losses from emitted radiation, convection, and ...
The direct absorption receiver (DAR) concept offers the potential of high temperature operation by using concentrated solar energy. This paper examines the minimum flow rate and other relevant issues required to maintain a continuous film flowing over the...
The problems involved in increasing the efficiency of cavity solar-energy collectors are considered when radiation-absorption surfaces with selective characteristics are employed. It is shown that in cavity-type solar collectors with selective radiation-absorption characteristics there is an optimum cavity depth ...
This report describes the repainting of a receiver panel at the 10 MWe Solar Thermal Central Receiver Pilot Plant located near Barstow, California. The plant, called Solar One, is a cooperative activity between the Department of Energy and the Associates: Southern California Edison, the Los Angeles Department of ...
The development of a new type of high temperature gas receiver that utilizes the direct absorption of concentrated solar flux by small particles suspended in the working fluid is described. The Small Particle Heat Exchange Receiver (SPHER) operates by inj...
The heat absorption and the attendant thermal and mechanical stressing of a solar heated receiver depend predominantly on the flux distribution of the incident solar radiation. A procedure for analyzing this flux distribution on the receiver internal surfaces is presented for a cavity ...
Sandia National Laboratories is investigating advanced central receiver concepts as part of the US Department of Energy solar thermal research program. In the last 12 years many studies and test programs have been carried out to develop and demonstrate the viability of central receiver power plants using ...
Absorption of solar radiation in the volume of a fluid rather than on the surface of its container can reduce heat losses from intermediate or high temperature systems where selective coatings become less effective or thermally unstable. In the model presented, for a new type of solar receiver, it is assumed that ...
The direct absorption receiver (DAR) is a solar thermal central receiver concept that, in contrast to state-of-the-art tubular receivers, directly exposes a flow of the working fluid to concentrated solar flux. Recent research indicates that using molten salts as the ...
This paper presents results of recent experiments on the Direct Absorption Receiver (DAR) concept using molten salt as the working fluid. The DAR concept may result in a solar central receiver that costs 50% less than the current tube receiver and has sig...
... cap absorption, and solar corpuscular streams are briefly ... Descriptors : *ABSORPTION, *SOLAR FLARES, *SOLAR RADIATION, COSMIC RAYS ...
A solar energy collection system and method for its utilization which is particularly efficient in collecting solar energy which has been concentrated at least up to 80 times, including a light focusing means, a single hollow receiver positioned to receive the focused rays directed from the focusing means with the ...
A solar energy receiver consists of an aluminum panel and a coating which comprises a black metal sulfide film having a high solar absorptance but a low thermal emissivity. A method for the production of such a receiver by wet chemical deposition onto an aluminum panel of a metal sulfide film ...
Absorption heat pumps have received renewed and increasing attention in the past two decades. The rising cost of electricity has made the particular features of this heat-powered cycle attractive for both residential and industrial applications. Solar-pow...
Solar reforming of methane with CO{sub 2} was demonstrated successfully with a direct absorption receiver/reactor on a parabolic dish capable of 150 kW solar power. The reactor, a volumetric absorber, consisted of a reticulated porous alumina foam disk coated with rhodium catalyst. The system was operated during ...
Solar reforming of methane with CO2 was demonstrated successfully with a direct absorption receiver/reactor on a parabolic dish capable of 150 kW solar power. The reactor, a volumetric absorber, consisted of a reticulated porous alumina foam disk coated with rhodium catalyst. The system was operated during both ...
Advanced central receiver concepts are currently being investigated as part of the US Department of Energy solar thermal research program. In the last 12 years many studies and test programs have been carried out to develop and demonstrate the viability of central receiver power plants using the tube-receivers with ...
As part of the Solar Thermal Technology Program, the direct absorption of sunlight by free-falling particles inside a cavity receiver is being evaluated. The objective of the ongoing optical properties measurement program is to obtain information to be us...
The Panel Research Experiment (PRE) is the first large-scale solar test of the molten nitrate salt direct absorption receiver (DAR) concept. The purpose of the PRE is to demonstrate the engineering feasibility and practicality of the DAR. We will conduct the test at the Central Receiver Test Facility in Albuquerque ...
allows two high-efficient thin-film solar devices to be stacked, allowing for much better absorption of light, and hence greater power. And one company that will receive up to $4...
National Renewable Energy Laboratory (NREL)
... Title : SOLAR ABSORPTANCE AND TOTAL HEMISPHERICAL EMITTANCE OF SURFACES FOR SOLAR ENERGY COLLECTION. ...
One receiver, a molten salt internal film receiver (IFR) is similar in concept to the Direct Absorption Receiver previously studied in the US. The Spanish Energy Agency CIEMAT, in consultation with us, designed and fabricated a test receiver 3 years ago b...
The aim of this work concerns the study of the silicone carbide fluidized bed in order to release a fluidized bed solar receiver with direct absorption of the concentrated solar radiation and to optimize the quantity of collected energy. For that, we tested several geometries in order to optimise the distribution ...
This report documents the results of a study on the technical and economic potential of high-temperature central receiver systems for producing electricity. The study covered three advanced high-temperature (1000/degree/-1400/degree/C) central receiver concepts: the direct absorption receiver, the particle ...
The CAtalytically Enhanced Solar Absorption Receiver (CAESAR) volumetrically absorbs concentrated solar energy throughout a catalyzed porous absorber matrix volume, promoting heterogeneous reactions with fluid-phase reactant species flowing through the ab...
An evacuated solar collector receives impinging solar radiation of varying intensity and converts the same into useful thermal energy in a selected working range of the ambience. The collector has absorber and window surfaces selectively coated for rendering the conversion of solar radiation to useful thermal ...
The heat transfer characteristics and performance of conically wound, single-layer monotube receivers for a concentrating solar collector are investigated. A discussion of methods and assumptions used to formulate the basic energy balances is presented. Results obtained from this analysis indicate the degree of sensitivity of performance to variations in ...
A solar concentrating lens and receiver operating on azimuth and altitude axes according to the position of the sun and characterized by an array of elongated transparent slats spaced for ventilation and each of prism-lens configuration with a reflective base, for both refractive and reflective focus of heat rays through a narrow slot into a ...
In a solar central receiver system Direct Absorption Receiver (DAR), the heat absorbing fluid (a blackened molten nitrate salt) flows in a thin film down a vertical panel (rather than through tubes as in conventional receiver designs) and absorbs the concentrated solar flux ...
A joint US/Federal Republic of Germany (FRG) project has successfully tested a unique solar-driven chemical reactor in the Catalytically Enhanced Solar Absorption Receiver (CAESAR) experiment. The CAESAR test was a proof-of-concept demonstration of carbon-dioxide reforming of methane in a commercial-scale, ...
The design and construction of a 1/4 MWt Air Cycle Solar Receiver has been completed and successfully tested at the Georgia Institute of Technology, Advanced Components Test Facility. The receiver was designed to deliver air at 1100/sup 0/C (2000/sup 0/F). The receiver operates at ambient pressure and does not ...
... efficiency of a solar energy collection surface in terms of its solar absorptance, total hemispherical emittance, solar power concentration (mirror or ...
The heat transfer and absorption characteristics of an external receiver pipe under unilateral concentrated solar radiation are theoretically investigated. Since the heat loss ratio of the infrared radiation has maximum at moderate energy flux, the heat absorption efficiency will first increase and then decrease ...
A rotating kiln has been built for tests coupling the solar central receiver at White Sands, New Mexico with the Zinc Sulfate Subcycle as part of a study on the thermochemical production of hydrogen from water. The kiln has been specially designed to help overcome some of the problems associated with using solar energy to heat ...
The development of a high temperature solar thermal gas receiver using direct absorption of concentrated sunlight by a suspension of small carbon particles is described. The Small Particle Heat Exchange Receiver (SPHER) can be used to power a Brayton cycle engine, supply industrial process heat or heat a gas to ...
... Title : THE RATIO OF ABSORPTION TO BACKSCATTER OF SOLAR RADIATION BY AEROSOLS DURING KHAMSIN CONDITIONS AND ...
... Accession Number : AD0656754. Title : SOLAR RADIATION AND ATMOSPHERIC ABSORPTION IN THE MM WAVE REGION. ...
... Title : POSSIBILITY OF ABSORPTION OF SOLAR LYMAN ALPHA RADIATION BY THE INTERPLANETARY MEDIUM,. Descriptive ...
Results are presented from a numerical model of the steady-state energy transfer in molten-salt-in-tube solar cavity receivers that includes convective energy transfer at a local (spatially resolved) level. Molten salt energy absorption and gray radiative transfer between all cavity surfaces are also included. This model is applied to ...
The concept of solar driven chemical reaction in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH[sub 4]) with ...
The concept of solar driven chemical reactions in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH{sub 4}) with ...
DOE Information Bridge
Thermochemical transport of solar energy based on reversible chemical reactions may be a way to take advantage of the high-temperature capabilities of parabolic dishes, while minimizing pipe network heat loss, since energy is transported at ambient temperatures in chemical form. Receiver/Reactor design is a key to making thermochemical transport a reality. ...
The angular scattering properties and scattering and absorption components of the extinction coefficient have been measured for Master Beads, an iron-doped Al sub 2 O sub 3 spheroid manufactured by Norton Chemical Co., Worcester, MA. This material, common...
A thermal energy transformer is described for use in combination with a heat engine. It comprises a flux receiver, having a first wall defining therein a radiation absorption cavity for converting solar flux to thermal energy characterized by a first wall...
Extensive studies, tests and analyses have been done to decrease the costs and to increase the efficiency of solar bowls. Solar bowls are by design (stationary collector with tracking receiver) not as efficient as full tracking systems but are inherently simple to construct and operate. Construction, test and analyses of reflective ...
Simplified Calculation of Solar Flux Distribution on Side Wall of Cylindrical Cavity Solar Receivers
NASA Technical Reports Server (NTRS)
Volumetric solar absorbers are designed to enable the penetration of radiation deep into the absorber in order to improve the efficiency of the energy transfer from incoming radiation to the working fluid. The design of such absorbers is usually based on the irradiation energy flux distribution. The authors show that the directional features of the irradiation also affect the ...
The use of solar energy to produce electricity is under development. High temperature fluid is heated by flowing through blackened receivers placed at the focus of concentrating collectors. This fluid is used to drive a conventional turbine working on Brayton cycle. The receivers should have high absorptance for ...
important role in the solar energy absorption and partitioning in the entire system. ... the absorption and distribution of solar energy in the ...
... Accession Number : AD0289037. Title : STUDY OF IONOSPHERIC ABSORPTION DURING A SOLAR ECLIPSE. PART I. SOLAR ECLIPSE. ...
Concentrating solar power (CSP) systems use solar absorbers to convert the heat from sunlight to electric power. Increased operating temperatures are necessary to lower the cost of solar-generated electricity by improving efficiencies and reducing thermal energy storage costs. Durable new materials are needed to cope with operating ...
This paper reports that a solar receiver-reactor has been designed to conduct solid-gas chemical reactions, using concentrated solar radiation as the energy source of high-temperature process heat. It consists of a conical cyclone gas-particle separator that has been modified to let concentrated solar energy enter ...
This paper presents results of recent experiments on the Direct Absorption Receiver (DAR) concept using molten salt as the working fluid. The DAR concept may result in a solar central receiver that costs 50% less than the current tube receiver and has significantly lower operational and ...
This paper presents results of experiments on the Direct Absorption Receiver (DAR) concept using molten salt as the working fluid. The DAR concept may result in a solar central receiver that costs 50 percent less than the current tube receiver and has significantly lower operational and ...
We have examined receiver-specific aspects of a direct absorption receiver (DAR) for use in a commercial solar central receiver system, emphasizing differences between previous salt-in-tube (SIT) receiver designs and the DAR. Our final design to accommodate the structural ...
Solar absorption characteristics are established for several films potentially favorable for use as receiving surfaces in solar energy collectors. Included in the investigation were chemically produced black films, black electrodeposits, and anodized coatings. It was found that black nickel exhibited the best ...
A portable type solar heat cooker assembly including a cooking glass tube comprising an outer bottomed glass tube and an inner bottomed glass tube coated with a selective absorption film showing a high absorptivity in the solar radiation spectrum zone and a low absorptivity in the heat ...
... Accession Number : AD0415086. Title : A RADIOMETER RECEIVER FOR SOLAR RESEARCH AT 480 MEGACYCLES,. ...
This report describes the design, construction, and testing of a solar central receiver using molten nitrate salt as a heat exchange fluid. Design studies for large commercial plants (30--100 MWe) have shown molten salt to be an excellent fluid for solar thermal plants as it allows for efficient thermal storage. Plant design studies ...
The direct absorption receiver (DAR) represents a fairly significant departure from conventional salt-in-tube receiver technology and appears to offer substantial promise for future generations of receivers. The DAR concept involves absorbing the solar flux directly into a film of molten salt ...
... Solar thermoelectrochemical, Reactors, Receivers ... RECEIVERS, THERMOCHEMISTRY, REACTOR SYSTEM COMPONENTS, WALLS ...
The purpose of the activities described in this report is to investigate an advanced gas receiver design concept. The advanced gas reactor design concept utilizes a translucent ceramic tube packed with a solar absorbing, porous material. A gas is pumped through the tube and is heated to a high temperature by direct solar energy ...
... of the receiver and the ... POSITIONING SYSTEM, *SOLAR ACTIVITY, *RADIO ... SYSTEMS, ELECTRONS, RECEIVERS, ARTIFICIAL SATELLITES ...
The optical absorption properties of a high-temperature molten-salt heat-transfer fluid were measured from 0.35 to 2.5 microns using both hemispherical transmission and reflection techniques. This fluid has application as a direct-absorbing working fluid in a high-temperature central-receiver solar-energy facility. To enhance its ...
A concept of a staggered selective volumetric receiver for central receiver systems is proposed. A physical model was developed which is able to calculate the temperature distribution within the receiver parallel to the flow direction. Solar and thermal radiation were taken into account as a function of the ...
... FOR USE IN A SOLAR CERAMIC RECEIVER FOR CHEMICAL ... USE IN HIGH-TEMPERATURE SOLAR RECEIVERS (HEAT EXCHANGERS) FOR ...
Sundstrand Energy Systems was awarded a contract to investigate the performance capabilities of a toluene heater tube integral to a heat pipe as applied to the Organic Rankine Cycle (ORC) solar dynamic power system for the Space Station. This heat pipe is a subassembly of the heat receiver. The heat receiver, the heat ...
A study was made of the optical characteristics required of a surface to convert solar radiant energy into sensible heat for a satellite electrical- generator system. It is shown that the absorptance for solar radiation of the surface should be high and is relatively of considerably more importance than the emittance of the ...
Two ceramic materials, spheroidized sintered bauxite and fused zircon, were evaluated for potential use as thermal transfer media in an advanced high temperature solid particle solar receiver. Both materials were sufficiently resistant to aggregation via sintering to permit repeated cycling of the particle charge to temperatures approaching 1400/sup 0/C ...
Two ceramic materials, spheroidized sintered bauxite and fused zircon, were evaluated for potential use as thermal transfer media in an advanced high temperature solid particle solar receiver. Both materials were sufficiently resistant to aggregation via sintering to permit repeated cycling of the particle charge to temperatures approaching 1400C provided ...
Multi-dimensional radiative transfer in combined mode heat transfer problems was investigated with emphasis on the analysis and characterization of a free-falling particle cloud, direct absorption solar central receiver. A model was developed to calculate the relevant distributions in the curtain while a concentrated ...
