Showing papers on "Nanofluids in solar collectors published in 1979"
TL;DR: For economical and efficient utilization of solar energy various types of absorber coatings and preparations can be used for solar collectors as discussed by the authors, and several varieties of commercial and research selective absorbers are reviewed and tabulated for application.
163 citations
TL;DR: In this paper, the efficiency of a typical basin type solar desalination plant is 30% or lower and the major design factors affecting energy utilization are basin temperature, condensing surface temperature and ambient air temperature.
90 citations
01 Jan 1979
TL;DR: A submitted manuscript is the author's version of the article upon submission and before peer-review as discussed by the authors, and the final published version features the final layout of the paper including the volume, issue and page numbers.
Abstract: • A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.
62 citations
TL;DR: In this article, the authors presented the use of porous flat plate collectors to achieve efficient heat extraction from an energy absorbing solid, and its application to solar air heaters, and analyzed the temperature distribution within a gas-cooled porous flatplate having its surface exposed to the sun's energy.
41 citations
Patent•
28 Mar 1979
TL;DR: In this paper, a combined solar converter which has a photovoltaic cell for converting the energy of solar radiation of a particular range of wavelengths to electricity and has a thermal heat absorber spaced from the cell, is presented.
Abstract: A combined solar converter which has a photovoltaic cell for converting the energy of solar radiation of a particular range of wavelengths to electricity and which has a thermal heat absorber spaced from the cell which converts solar radiation of longer wavelengths passing from the cell to useful heat. A method of utilizing solar energy comprising the step of subjecting a photovoltaic cell to solar radiation to convert energy of a particular range of wavelengths to which the cell is sensitive to electricity and transferring long wave radiations passing from a cell to a heat absorber spaced from the cell where the energy of the long wave radiation is transferred to useful heat.
36 citations
Patent•
19 Nov 1979
TL;DR: In this paper, a collector is designed and positioned for installations within a predetermined range of latitudes without modification of collector position, construction, or tracking the sun's movement, and comprises a generator of hot or cold fluid by solar energy collection during the day to heat the fluid and/or chilling of the fluid at nocturnal nighttime.
Abstract: This invention is directed to a collector designed and positioned for installations within a predetermined range of latitudes without modification of collector position, construction, or tracking the sun's movement, and comprises a generator of hot or cold fluid by solar energy collection during the day to heat the fluid and/or chilling of the fluid at nocturnal nighttime.
29 citations
Patent•
13 Aug 1979
TL;DR: In this article, a solar heating system for a swimming pool and the like is described, which includes a circulation circuit having a pump by which water is withdrawn from the pool, passed through a filter and returned to the pool.
Abstract: A solar heating system for a swimming pool and the like is disclosed. The system includes a circulation circuit having a pump by which water is withdrawn from the pool, passed through a filter and returned to the pool. A solar collector assembly is provided and has flow and return lines connected in said circuit. The flow line is connected to a venturi unit in the main circuit and a control valve is provided immediately downstream of the venturi unit. When the control valve is closed, water is diverted through the venturi unit and into the solar collector assembly for heating. When the valve is open, the venturi unit induces a suction effect in the flow line which causes the solar collector assembly to be positively drained into the circuit. A vacuum breaker admits air to the collector assembly at this time.
29 citations
TL;DR: In this article, the daily and annual radiative performance of a trough-like collector with depth-to-base ratios ranging from 1.1 to 5 was analyzed and the results were based on assumed tilting routines chosen to match the collector's capabilities.
25 citations
TL;DR: In this article, an analysis of the heat transfer process in the corrugated steel sheet solar water heater and a simplified test procedure for determining the collector efficiency equation are presented, which coincides with that obtained by the standard procedure.
25 citations
Patent•
26 Dec 1979
TL;DR: In this paper, a small independent heat exchanger between the solar collector and the water heater and a vacuum breaking system was used to drain the water in the solar collectors into the heat exchangers.
Abstract: In a solar water system including a solar collector prevention of damage to the collector during freezing conditions is achieved by providing a relatively small independent heat exchanger between the solar collector and the water heater and a vacuum breaking system whereby the water in the solar collector is drained into the heat exchanger. The heat exchanger is connected to a thermal siphon arrangement with the water heater.
Patent•
11 Jun 1979
TL;DR: In this paper, a concentrated saline solution is used to store solar energy for both heating and cooling, and a small uninsulated tank is used for storing the desiccant solution so that the heat pump can operate at night or during extended periods when the sun is obscured.
Abstract: A concentrated saline solution is used to store solar energy for both heating and cooling. A small, uninsulated tank is used to store the desiccant solution so that the heat pump can operate at night or during extended periods when the sun is obscured. No vacuum or pressure refrigerant systems are needed. Reconcentration of the sorbent solution is accomplished by direct solar radiation.
TL;DR: In this article, a fixed solar thermal energy collector is designed by proceeding carefully through a series of optimization steps to obtain near optimum performance, while retaining features that should lead to low cost.
Patent•
28 Jun 1979
TL;DR: In this article, a multi-system solar collector with a unique design is described, which allows the collector unit to absorb energy from radiation, conduction, and convection, and utilizes a dry gas at higher than atmospheric pressure to form the working fluid for the convection heat transfer.
Abstract: This invention relates to solar collector apparatus in general and more specifically to a multi systems solar collector which has a unique design which allows the collector unit to absorb energy from radiation, conduction and convection. The device in question also utilizes a dry gas at higher than atmospheric pressure to form the working fluid for the convection heat transfer.
Patent•
21 Aug 1979
TL;DR: In this paper, an apparatus for the preparation of hot water using solar energy and non-solar auxiliary energy is presented. But the equipment is not suitable for outdoor use and it is not equipped with an auxiliary gas heater.
Abstract: An apparatus for the preparation of hot water using solar energy and non-solar auxiliary energy. Solar heated water in a reservoir is provided for utilization if it is at least at a desired temperature. If the solar heated water is not sufficiently hot, an auxiliary gas heater is used to heat a second reservoir of water to at least the desired temperature. A thermostatic mixer is capable of supplying solar heated water mixed with auxiliary heated water, or only auxiliary heated water, or only solar heated water for utilization. The non-solar heater is utilized only when necessary.
TL;DR: A solar cooling, heating, and hot water supply system for the hospital with evacuated glass tube type solar collectors was described in this article, where the results of the performance of the solar collectors in the large scale system were shown for one year operation.
Patent•
21 May 1979
TL;DR: In this paper, the constructional structure of a solar collector has been simplified in such a way that the condenser system of the collector is inserted in the channel through which the gaseous or liquid heat-transfer medium flows by means of a sealing system comprising a gasket member and screwably operable tightening means.
Abstract: A solar collector is disclosed the constructional structure of which has been simplified in such a way that the condenser system of the collector is inserted in the channel through which the gaseous or liquid heat-transfer medium flows by means of a sealing system comprising a gasket member and screwably operable tightening means. Assembly and overhauling of the condenser system are greatly facilitated.
TL;DR: In this article, a simulation study has been conducted of the influence of cover design on the thermal performance of flat-plate solar collectors for use at temperatures of 150°C, and the effects of changes in cover materials, cover surface treatments, cover system configuration and absorber plate surface treatments on both the instantaneous efficiency and the long term solar contribution of flatplate collectors were analyzed.
Patent•
02 Jan 1979TL;DR: An improved transparent laminar structure useful as a window in a solar collector having an absorber characterized with a low absorption/emission ratio is described in this article, where a glass substrate, a particularly defined infrared-reflecting (IRR) layer provided on a major surface of the substrate, and a solar reflection-reducing layer of polymethacrylate composition provided on the IRR layer.
Abstract: An improved transparent laminar structure useful as a window in a solar collector having an absorber characterized with a low absorption/emission ratio is described. The structure includes a glass substrate, a particularly defined infrared-reflecting (IRR) layer provided on a major surface of the substrate, and a solar reflection-reducing layer of polymethacrylate composition provided on the IRR layer. Also described are an improved solar collector and method for collecting solar radiation, wherein the laminar structure is employed.
TL;DR: In this paper, the potential of fluorescent collectors for thermal conversion is evaluated theoretically and the conversion efficiencies are calculated for various configurations and operating temperatures, showing that fluorescent collectors, although having a lower initial efficiency than flat plate collectors retain this efficiency at high operating temperatures and at low solar flux intensity.
Patent•
31 Jul 1979
TL;DR: In this paper, a plurality of assembled solar energy collector elements are assembled at one end and water heated by the solar energy is drawn off at the other end of the device, where the liquid circulates through the device in contact with an absorbent mat of intermingled fibers.
Abstract: Comprising a plurality of assembled solar energy collector elements. Cold liquid is supplied at one end and water heated by the solar energy is drawn off at the other end of the device. The liquid circulates through the device in contact with an absorbent mat of intermingled fibers of dark color which is exposed to the solar radiation through at least one translucent sheet which creates a glasshouse effect. The mat guides the flow of liquid by the effect of capillarity and gravity during the heating of the liquid.
TL;DR: In this paper, the authors presented an analysis of the performance of an inexpensive constant flow solar collector/storage system, which has been validated by experiments and showed that for a 7 cm depth of the plane of heat retrieval and 81/min flow rate of water, the collection efficiency of the system is 20.0 per cent.
Abstract: This paper presents an analysis of the performance of an inexpensive constant flow solar collector/storage system, which has been validated by experiments. the system consists of a network of pipes buried in the ground, the top surface of the ground being blackened by black board paint spray and suitably glazed. the heat can be extracted by flow of fluid in the pipes at a constant flow rate. It is seen that for a 7 cm depth of the plane of heat retrieval and 81/min flow rate of water, the collection efficiency of the system is 20.0 per cent. the efficiency increases with flow rate and decreases with the depth of the plane of heat retrieval.
Patent•
19 Apr 1979
TL;DR: A concentrating vacuum insulated solar energy collecting and converting apparatus employing transfer means for selectively moving the collected energy back through the vacuum preservation means for useful purposes is described in this paper, where the transfer means can be used for transferring the energy collected from the solar panels to the ground.
Abstract: A concentrating vacuum insulated solar energy collecting and converting apparatus employing transfer means for selectively moving the collected energy back through the vacuum preservation means for useful purposes.
TL;DR: In this paper, high temperature heat engines designed to make maximum use of the thermodynamic potential of concentrated solar radiation are described, and two machines capable of expanding hot plasmas using practical technology are discussed.
Abstract: High temperature heat engines designed to make maximum use of the thermodynamic potential of concentrated solar radiation are described. Plasmas between 2000 K and 4000 K can be achieved by volumetric absorption of radiation in alkali metal vapors, leading to thermal efficiencies up to 75% for terrestrial solar power plants and up to 50% for space power plants. Two machines capable of expanding hot plasmas using practical technology are discussed. A binary Rankine cycle uses fluid mechanical energy transfer in a device known as the 'Comprex' or 'energy exchanger.' The second machine utilizes magnetohydrodynamics in a Brayton cycle for space applications. Absorption of solar energy and plasma radiation losses are investigated for a solar superheater using potassium vapor.
Patent•
06 Apr 1979
TL;DR: In this paper, a generator of electric energy by the transformation of thermal, solar energy, or of heat of any source, consisting in one or more thermocouples combined with a cooling device, cooling down the weldings of the thermocouple on which heat is produced by the Peltier effect, also producing a very high thermal gradient.
Abstract: A generator of electric energy by the transformation of thermal, solar energy, or of heat of any source, consisting in one or more thermocouples combined with a cooling device, cooling down the weldings of the thermocouples on which heat is produced by the Peltier effect, also producing a very high thermal gradient. The cooling device exploits, for the functioning thereof, the phenomena which can be observed along the thermocouples. The system for the use of such a generator provides a particular disposition of the same in parabolic collectors, as to increase the sun ray concentration onto the weldings exposed to the heat and as to allow a decentralization in the electric energy supply by means of a plurality of generators consisting in only one thermocouple, said generators being interconnected.
TL;DR: In this paper, the optical shape of the heater's surface of solar energy concentrating collectors is examined and the multi reflection effect, through a macrocavity analysis, is introduced.
Abstract: The optical shape of the heater's surface of solar energy concentrating collectors is here examined. Multi reflection effect, through a macrocavity analysis is introduced. The optical design of the cavity is accomplished and the cavity effect determined. Thermotechnical analysis of the system, in order to determine the optimal conditions for the heat transfer and for the maximization of the energy radiative balance, is introduced.
Patent•
07 Dec 1979
TL;DR: In this article, a solar heating system for supplying heated air to various portions of a building is described, where a solar panel is mounted externally of the building and a solar air heating chamber is defined.
Abstract: A solar heating system for supplying heated air to various portions of a building. A solar panel is mounted externally of the building. The solar panel includes a solar radiation absorbing plate and a solar radiation transmissive plate spaced from the absorbing plate to define a solar air heating chamber. Ducts leading from the building circulate air through the solar air heating chamber. The heated air is then distributed throughout the building. The heat extraction unit of a fireplace can also be connected to the distributing duct work. Both the solar panel and the heat extraction unit additionally can be used to heat water.
Patent•
31 Jan 1979
TL;DR: In this paper, a solar collector assembly comprising a hollow housing body that is at least partially transparent is described, where an absorber means is contained in the housing and a vacuum pump means is connected to the housing.
Abstract: The invention relates to a solar collector assembly comprising a hollow housing body that is at least partially transparent. An absorber means is contained in the housing and a vacuum pump means is connected to the housing. A particular process of operating the solar collector assembly also forms a part of this invention. Solar collector assemblies are used for converting sun energy into other forms of energy such as heat used to prepare hot water or heat for energy production. Many attempts have been made to design solar collectors having a compact structural shape and satisfactory efficiency to render them suitable as an energy source in dwelling houses. However, such a solar collector has not yet been attained.