The Experts below are selected from a list of 1812 Experts worldwide ranked by ideXlab platform
Nasa - One of the best experts on this subject based on the ideXlab platform.
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Installation package for Concentrating Solar Collector panels
2013Co-Authors: NasaAbstract: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.
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Concentrating Solar Collector subsystem: Preliminary design package
2013Co-Authors: NasaAbstract:Preliminary design data are presented for a Concentrating Solar Collector including an attitude controller. Provided are schedules, technical status, all documents required for preliminary design, and other program activities.
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Performance evaluation of the Solar kinetics T-700 line Concentrating Solar Collector
2013Co-Authors: NasaAbstract:A performance evaluation of the Solar kinetics T-700 line Concentrating Solar Collector is reported. Collector descriptions, summary, test conditions, test equipment, test requirements and procedures, and an analysis of the various tests performed are described.
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Design package for Concentrating Solar Collector panels
2013Co-Authors: NasaAbstract: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.
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Development and fabrication of a Concentrating Solar Collector subsystem
2013Co-Authors: NasaAbstract:The progress of work on the evacuated receiver, lens design, lens die fabrication, and improvements on components, production techniques, and performance testing is discussed.
R Z Wang - One of the best experts on this subject based on the ideXlab platform.
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comparison of absorption refrigeration cycles for efficient air cooled Solar cooling
Solar Energy, 2018Co-Authors: Z Y Xu, R Z WangAbstract:Abstract Absorption chiller is a widely used technology owing to its capability to utilize low grade thermal energy including Solar thermal energy and waste heat. Yet, most Solar absorption cooling systems need cooling tower to dissipate heat rejection into ambient. The use of cooling tower increases both the initial investment and water consumption, which can be improved by air-cooled Solar absorption cooling system. In this paper, to give the best absorption cycle options under different conditions, five absorption refrigeration cycles suitable for air-cooled Solar cooling including three double lift absorption cycles and two semi-GAX (Generator-Absorber heat eXchange) absorption cycles were compared. Steady-state simulation is carried out. Efficiencies of these cycles were calculated with LiBr-water and water-ammonia working pairs in the scenario of air-cooled Solar cooling. Heat source temperatures of 75–100 °C from non-Concentrating Solar Collector and air temperatures of 20–40 °C were considered. Both air-conditioning condition with evaporation temperature of 5 °C and sub-zero condition with −10 °C were discussed. It is found that mass-coupled semi-GAX absorption cycle with ammonia-water is suitable for air-conditioning with higher heat source temperatures, mass-coupled double lift absorption cycle with water-LiBr is suitable for air-conditioning with lower heat source temperature and mass-coupled double lift absorption cycle with ammonia-water is suitable for sub-zero conditions.
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experimental investigation and analysis on a Concentrating Solar Collector using linear fresnel lens
Energy Conversion and Management, 2010Co-Authors: Hui Zhai, Yanjun Dai, R Z Wang, Liang ZhangAbstract:Abstract A Concentrating Solar Collector based on linear Fresnel lens is investigated experimentally in this paper. This Solar Collector is expected to acquire a higher thermal efficiency at a relatively high temperature level than the commonly used flat-plate or evacuated tube Solar Collectors. Experimental results show that the thermal efficiency is about 50% when the conversion temperature (water) is 90 °C. The test shows that the indication of lost energy is 0.578 W/m2 K, which is much smaller than that of commonly used evacuated tube Solar Collector without Concentrating. In order to make analysis, a mathematical model for evacuated tube absorber heated by linear Fresnel lens has been built. The validation shows that the model agrees with the experimental data well. The analysis indicates that Fresnel lens Collector with evacuated tube absorber has good efficiency (50%) in clear day even when the conversion temperature approaches 200 °C. The influence of ambient conditions and the percent of different types of energy loss, etc., are also analyzed.
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study on trough receiver for linear Concentrating Solar Collector
2008Co-Authors: Hui Zhai, Yanjun Dai, R Z WangAbstract:In this paper, a trough black body cavity receiver for linear Concentrating Collector, which has potential application at moderate working temperatures (near 100°C) or higher temperature (above 180°C), has been studied. Four different shapes of the receiver have been proposed and tested. The optical efficiencies of the four receivers are simulated by using light tracking method. The thermal performances of the cavity receivers are tested under temperature levels, 90°C and 150°C, where the concentrated Solar radiation is simulated by electric heating film. Both optical and thermal analysis illustrates that the triangle trough receiver is the best choice. To reduce the thermal losses, three kinds of glass cover are fixed on the cavity receiver. The thermal losses of the three different receivers with glass cover have been tested, when the inlet temperature varies from 35°C to 95°C. The experimental results indicate that the glass cover can reduce the thermal losses effectively. The semicircular cavity is tested in an linear Concentrating Solar Collector, in which the sunlight is concentrated by a linear Fresnel lens(aperture width is 0.4m and optical efficiency is 0.7) and scatters on the semicircular cavity wall, absorbed by the copper tube and transmitted to working fluid. The highest average efficiency can reach 43% when the inlet temperature of the working fluid is 90°C. It is found from experimental results that the efficiency of this designed cavity receiver is a little lower than that of evacuated tube, but has good potential in application because it is cheap and can be manufactured easily.
Murat Ozturk - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic investigation of a Concentrating Solar Collector based combined plant for poly generation
International Journal of Hydrogen Energy, 2020Co-Authors: Fatih Yilmaz, Murat Ozturk, Resat SelbasAbstract:Abstract The detailed thermodynamic evaluation for combined system assisted on Solar energy for poly-generation are studied in this paper. This poly-generation cycle is operated by the Concentrating Solar radiation by using the parabolic dish Solar Collector series. The beneficial exits of this integrated plant are the electricity, fresh-water, hot-water, heating-cooling, and hydrogen while there are different heat energy recovery processes within the plant for development performance. A Rankine cycle with three turbines is employed for electricity production. In addition to that, the desalination aim is performed by utilizing the waste heat of electricity production cycle in a membrane distillation unit for fresh-water generation. Also, a PEM electrolyzer sub-component is utilized for hydrogen generation aim in the case of excess power generation. Finally, the hot-water production cycle is performed via the exiting working fluid from the very high-temperature generator of the cooling cycle. Moreover, based on the thermodynamic assessment outputs, the whole energy and exergy efficiencies of 58.43% and 54.18% are computed for the investigated Solar plant, respectively.
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Thermodynamic Performance Evaluation of Concentrating Solar Collector with Supercritical Carbon Dioxide (sCO_2) Base Nanofluids
Arabian Journal for Science and Engineering, 2020Co-Authors: Vahit Corumlu, Recep Onur Uzun, Murat OzturkAbstract:The use of supercritical carbon dioxide as a working fluid is an important alternative to enable the use of parabolic Collectors in the high-temperature applications field. In the present paper, the effects of carbon black nanoparticles dispersed in supercritical carbon dioxide (sCO_2) base fluid on the energetic and exergetic performance of parabolic trough Collectors are theoretically investigated. Thermal modeling and performance analyses are performed through the developed model in the Engineering Equation Solver software. To present operating conditions of the system, all working fluids are tested under a pressure of 80 bar at a mass flow rate of 1.1 kg/s. In these analyses, the fluid inlet temperature, ambient temperature, and nanofluid concentration are determined as the variable indicators. Up to approximately working fluid inlet temperature of 705 K, the exergy efficiencies of the Concentrating Collectors using the sCO_2 nanofluids are higher than that of the Concentrating Collector using the sCO_2 base fluid. Additionally, the exergy efficiency increases in the systems using nanofluids with 2% and 4% concentration ratio are between 0.34–6.96% and 0.49–11.44%, respectively, according to the system using base fluid. Besides, at the working fluid inlet temperature values greater than 705 K, the exergy efficiency of the Collector of using the sCO_2 working fluid is found higher than the Collectors using the nanofluids. However, at the same working fluid inlet temperatures, the fluid outlet temperatures of the Collectors with the sCO_2 nanofluids are higher than the system with sCO_2 working fluid.
Vikrant Khullar - One of the best experts on this subject based on the ideXlab platform.
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on sun testing of volumetric absorption based Concentrating Solar Collector employing carbon soot nanoparticles laden fluid
Sustainable Energy Technologies and Assessments, 2020Co-Authors: Nirmal Singh, Vikrant KhullarAbstract:Abstract In the present work, a nanofluid based volumetrically absorbing Solar receiver having reflecting inner surfaces has been tested under outdoor conditions. Carbon soot nanoparticles from used motor oil dispersed in paraffin oil forms the working fluid. Results show that steady-state thermal efficiency peaks at an optimum nanoparticles volume fraction (ηth = 59 ± 4% at fv = 1%). Furthermore, the as-prepared nanofluid shows excellent stability i.e. it retains its optical characteristics and particle size distribution even after undergoing pumping and thermal cycles and moving in flow loops (circulation through pipes/valves) during on-sun testing. Moreover, the as-prepared nanofluid has negligible impact on the surface and optical properties of Solar receiver constituent materials. Overall, the proposed receiver design and the as-prepared nanofluid stability represent significant steps towards realization of practical nanofluid based volumetric absorption Solar thermal systems.
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Applicability of Heat Mirrors in Reducing Thermal Losses in Concentrating Solar Collectors
Volume 6B: Energy, 2016Co-Authors: Prashant Mahendra, Vikrant Khullar, M.k. MittalAbstract:Flux distribution around the parabolic trough receiver being typically non-uniform, only a certain portion of the receiver circumference receives the concentrated Solar irradiance. However, radiative and convective losses occur across the entire receiver circumference. This paper attempts to introduce the idea employing transparent heat mirror to effectively reduce the heat loss area and thus improve the thermal efficiency of the Solar Collector. Transparent heat mirror essentially has high transmissivity in the Solar irradiance wavelength band and high reflectivity in the mid-infrared region thus it allows the Solar irradiance to pass through but reflects the infrared radiation back to the Solar selective metal tube. Practically, this could be realized if certain portion of the conventional low iron glass envelope is coated with Sn-In2O3 so that its acts as a heat mirror.In the present study, a parabolic receiver design employing the aforesaid concept has been proposed. Detailed heat transfer model has been formulated. The results of the model were compared with the experimental results of conventional Concentrating parabolic trough Solar Collectors in the literature. It was observed that while maintaining the same external conditions (such as ambient/initial temperatures, wind speed, Solar insolation, flow rate, concentration ratio etc.) the heat mirror-based parabolic trough Concentrating Solar Collector has about 3–12% higher thermal efficiency as compared to the conventional parabolic Solar Collector. Furthermore, steady state heat transfer analysis reveals that depending on the Solar flux distribution there is an optimum circumferential angle (θ = θoptimum, where θ is the heat mirror circumferential angle) up to which the glass envelope should be coated with Sn-In2O3. For angles higher than the optimum angle, the Collector efficiency tends to decrease owing to increase in optical losses.Copyright © 2016 by ASME
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Solar energy harvesting using nanofluids based Concentrating Solar Collector
Journal of Nanotechnology in Engineering and Medicine, 2012Co-Authors: Vikrant Khullar, Patrick E. Phelan, Himanshu Tyagi, Todd Otanicar, Harjit Singh, Robert A. TaylorAbstract:Dispersing trace amounts of nanoparticles into the base-fluid has significant impact on the optical as well as thermo-physical properties of the base-fluid. This characteristic can be utilized in effectively capturing as well as transporting the Solar radiant energy. Enhancement of the Solar irradiance absorption capacity of the base fluid scales up the heat transfer rate resulting in higher & more efficient heat transfer. This paper attempts to introduce the idea of harvesting the Solar radiant energy through usage of nanofluid-based Concentrating parabolic Solar Collectors. In order to theoretically analyze the nanofluid-based Concentrating parabolic Solar Collector (NCPSC) it has been mathematically modeled, and the governing equations have been numerically solved using finite difference technique. The results of the model were compared with the experimental results of conventional Concentrating parabolic Solar Collectors under similar conditions. It was observed that while maintaining the same external conditions (such as ambient/inlet temperatures, wind speed, Solar insolation, flow rate, concentration ratio etc.) the NCPSC has about 5–10% higher efficiency as compared to the conventional parabolic Solar Collector. Furthermore, some parametric studies were carried out which reflected the effect of various parameters such as Solar insolation, incident angle, convective heat transfer coefficient etc. on the performance indicators such as thermal efficiency etc.Copyright © 2012 by ASME
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Solar energy harvesting using nanofluids based Concentrating Solar Collector
Journal of Nanotechnology in Engineering and Medicine, 2012Co-Authors: Vikrant Khullar, Patrick E. Phelan, Himanshu Tyagi, Todd Otanicar, Harjit Singh, Robert A. TaylorAbstract:Dispersing trace amounts of nanoparticles into the base-fluid has significant impact on the optical as well as thermo-physical properties of the base-fluid. This characteristic can be utilized in effectively capturing as well as transporting the Solar radiant energy. Enhancement of the Solar irradiance absorption capacity of the base fluid scales up the heat transfer rate resulting in higher & more efficient heat transfer. This paper attempts to introduce the idea of harvesting the Solar radiant energy through usage of nanofluid-based Concentrating parabolic Solar Collectors. In order to theoretically analyze the nanofluid-based Concentrating parabolic Solar Collector (NCPSC) it has been mathematically modeled, and the governing equations have been numerically solved using finite difference technique. The results of the model were compared with the experimental results of conventional Concentrating parabolic Solar Collectors under similar conditions. It was observed that while maintaining the same external conditions (such as ambient/inlet temperatures, wind speed, Solar insolation, flow rate, concentration ratio etc.) the NCPSC has about 5–10% higher efficiency as compared to the conventional parabolic Solar Collector. Furthermore, some parametric studies were carried out which reflected the effect of various parameters such as Solar insolation, incident angle, convective heat transfer coefficient etc. on the performance indicators such as thermal efficiency etc.Copyright © 2012 by ASME
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Solar Energy Harvesting Using Nanofluids-Based Concentrating Solar Collector
ASME 2012 Third International Conference on Micro Nanoscale Heat and Mass Transfer, 2012Co-Authors: Vikrant Khullar, Patrick E. Phelan, Himanshu Tyagi, Todd Otanicar, Harjit Singh, Robert A. TaylorAbstract:Dispersing trace amounts of nanoparticles into the base-fluid has significant impact on the optical as well as thermo-physical properties of the base-fluid. This characteristic can be utilized in effectively capturing as well as transporting the Solar radiant energy. Enhancement of the Solar irradiance absorption capacity of the base fluid scales up the heat transfer rate resulting in higher & more efficient heat transfer. This paper attempts to introduce the idea of harvesting the Solar radiant energy through usage of nanofluid-based Concentrating parabolic Solar Collectors. In order to theoretically analyze the nanofluid-based Concentrating parabolic Solar Collector (NCPSC) it has been mathematically modeled, and the governing equations have been numerically solved using finite difference technique. The results of the model were compared with the experimental results of conventional Concentrating parabolic Solar Collectors under similar conditions. It was observed that while maintaining the same external conditions (such as ambient/inlet temperatures, wind speed, Solar insolation, flow rate, concentration ratio etc.) the NCPSC has about 5–10% higher efficiency as compared to the conventional parabolic Solar Collector. Furthermore, some parametric studies were carried out which reflected the effect of various parameters such as Solar insolation, incident angle, convective heat transfer coefficient etc. on the performance indicators such as thermal efficiency etc.
Tomas Nunez - One of the best experts on this subject based on the ideXlab platform.
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Solar cooling with water ammonia absorption chillers and Concentrating Solar Collector operational experience
International Journal of Refrigeration-revue Internationale Du Froid, 2014Co-Authors: Christine Weber, Michael Berger, Florian Mehling, Alexander Heinrich, Tomas NunezAbstract:Abstract Concentrating Solar Collectors provide high efficiency at high driving temperatures favourable for thermally driven chillers. Therefore, they offer applications for hot climates and industrial process integration, especially in combination with NH3–H2O chillers that provide refrigeration temperatures below 0 °C. The presented Solar cooling installation comprises a linear Concentrating Fresnel Collector that provides the driving heat for two NH3–H2O absorption chillers at temperatures up to 200 °C. Chilled water temperatures are produced in the range between −12 °C and 0 °C. Collector capacities reached up to 70 kW at peak times and the total cooling capacity of both chillers showed peak values up to 25 kW. For good operating conditions, the thermal system EER was 0.8 and an electrical system EER of 12 was easily achieved. The system showed a sound operating behaviour. The performance of different operation and control strategies was analysed, evaluated and enhanced within the two year operation phase.
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Solar cooling with water–ammonia absorption chillers and Concentrating Solar Collector – Operational experience
International Journal of Refrigeration, 2014Co-Authors: Christine Weber, Michael Berger, Florian Mehling, Alexander Heinrich, Tomas NunezAbstract:Abstract Concentrating Solar Collectors provide high efficiency at high driving temperatures favourable for thermally driven chillers. Therefore, they offer applications for hot climates and industrial process integration, especially in combination with NH3–H2O chillers that provide refrigeration temperatures below 0 °C. The presented Solar cooling installation comprises a linear Concentrating Fresnel Collector that provides the driving heat for two NH3–H2O absorption chillers at temperatures up to 200 °C. Chilled water temperatures are produced in the range between −12 °C and 0 °C. Collector capacities reached up to 70 kW at peak times and the total cooling capacity of both chillers showed peak values up to 25 kW. For good operating conditions, the thermal system EER was 0.8 and an electrical system EER of 12 was easily achieved. The system showed a sound operating behaviour. The performance of different operation and control strategies was analysed, evaluated and enhanced within the two year operation phase.