Solar Dish Collector Research Papers (original) (raw)

Abstract Modeling and simulation for different parabolic dish Stirling engine designs have been carried out using Matlab®. The effect of solar dish design features and factors such as material of the reflector concentrators, the shape of the reflector concentrators and the receiver, solar radiation at the concentrator, diameter of the parabolic dish concentrator, sizing the aperture area of concentrator, focal Length of the parabolic dish, the focal point diameter, sizing the aperture area of receiver, geometric concentration ratio, and rim angle have been studied. The study provides a theoretical guidance for designing and operating solar parabolic dish Stirling engines system. At Zewail city of Science and Technology, Egypt, for a 10 kW Stirling engine; The maximum solar dish Stirling engine output power estimation is 9707 W at 12:00 PM where the maximum beam solar radiation applied in solar dish concentrator is 990 W/m 2 at 12:00 PM. The performance of engine can be improved by increasing the precision of the engine parts and the heat source efficiency. The engine performance could be further increased if a better receiver working fluid is used. We can conclude that where the best time for heating the fluid and fasting the processing, the time required to heat the receiver to reach the minimum temperature for operating the Solar-powered Stirling engine for different heat transfer fluids; this will lead to more economic solar dish systems. Power output of the solar dish system is one of the most important targets in the design that show effectiveness of the system, and this has achieved when we take into account many factors in the design of the solar dish system. One of these factors is the reflector material of the concentrator and using the results from the Matlab simulation program; where the Polymeric Film, Non Metal reflectors, with a net conversion power of more than 97.07%, still holds the conversion record than the Anod Aluminum reflectors, which has a net conversion power 85.97% with respect to the polished stainless reflectors with a net conversion power 49.52% from the 10 kW Stirling engine. Where the power output differ as 9707, 4952, 8597 W, respectively from the 10 kW Stirling engine. It is shown that there are changes in Stirling power output for different materials, which guide us to select the optimum material, based on the targeted power output and cost. Our target to reach the optimum power that we need it in the design 10 kW power output design as an example from the solar dish Stirling engine.

- by
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- Matlab, Solar Energy, Stirling engine, Solar Dish Collector

Dans une période où l’énergie est une problématique majeure, de nouvelles pistes sont explorées permettant sa production. Dans cette optique, et afin d’y associer une notion de production autonome et renouvelable, la centrale solaire à... more

- by Alexis Chatenet
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- Science Education, Renewable Energy, Solar Energy, Solar Dish Collector

In this paper, a feasibility study is carried out in order to investigate the description, working principles of the solar parabolic dish systems worldwide, and their potential use in some countries are given. A study of the system is presented, which able to show the performance of the system and accounting for the main technical aspects of the concentrator, receiver and Stirling engine. The study reviews the parabolic solar dish technologies and the design factors adapted in different applications such as material of the reflector concentrators, shape of the reflector concentrators and the receiver, solar radiation at the concentrator, diameter of the parabolic dish concentrator, sizing the aperture area of concentrator, focal length of the parabolic dish, the focal point diameter, sizing the aperture area of receiver, geometric concentration ratio, and rim angle. In order to identify the optimum design feasible option for installation of the solar dish plants, the technical characteristics of some implemented solar dishes worldwide are presented. The study take into consideration available solar potential and the different designs of solar dishes.

- by A. Z. Hafez
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- Renewable Energy, Energy, Solar Energy, Stirling engine

Modeling and simulation for different parabolic dish Stirling engine designs have been carried out using Matlab. The effect of solar dish design features and factors such as material of the reflector concentrators, the shape of the reflector concentrators and the receiver, solar radiation at the concentrator, diameter of the parabolic dish concentrator, sizing the aperture area of concentrator, focal Length of the parabolic dish, the focal point diameter, sizing the aperture area of receiver, geometric concentration ratio, and rim angle have been studied. The study provides a theoretical guidance for designing and operating solar parabolic dish Stirling engines system. At Zewail city of Science and Technology, Egypt, for a 10 kW Stirling engine; The maximum solar dish Stirling engine output power estimation is 9707W at 12:00 PM where the maximum beam solar radiation applied in solar dish concentrator is 990 W/m2 at 12:00 PM. The performance of engine can be improved by increasing the precision of the engine parts and the heat source efficiency. The engine performance could be further increased if a better receiver working fluid is used. We can conclude that where the best time for heating the fluid and fasting the processing, the time required to heat the receiver to reach the minimum temperature for operating the Solar-powered Stirling engine for different heat transfer fluids; this will lead to more economic solar dish systems.
Power output of the solar dish system is one of the most important targets in the design that show effectiveness of the system, and this has achieved when we take into account many factors in the design of the solar dish system. One of these factors is the reflector material of the concentrator and using the results from the Matlab simulation program; where the Polymeric Film, Non Metal reflectors, with a net conversion power of more than 97.07%, still holds the conversion record than the Anod Aluminum reflectors, which has a net conversion power 85.97% with respect to the polished stainless reflectors with a net conversion power 49.52% from the 10 kW Stirling engine. Where the power output differ as 9707, 4952, 8597 W, respectively from the 10 kW Stirling engine. It is shown that there are changes in Stirling power output for different materials, which guide us to select the optimum material, based on the targeted power output and cost. Our target to reach the optimum power that we need it in the design 10 kW power output design as an example from the solar dish Stirling engine.

- by A. Z. Hafez
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- Matlab, Solar Energy, Stirling engine, Solar Dish Collector

1. Introduzione Gli ambiziosi obiettivi nazionali, fissati dalla Commissione Europea per l'anno 2020, pari ad una copertura con le energie rinnovabili al 17% degli usi finali di energia, non-ché le indicazioni verso l'autoproduzione e la distribuzione locale di energia da fonti rinnovabili indicate nella nuova proposta della Commissione Europea sulle rinnovabili, di-rettiva (UE) 2018/2001 del Parlamento Europeo e del Consiglio, risultano fondamentali da perseguire, ma non semplici da conseguire. Senza dubbio, un ruolo fondamentale per il loro raggiun-gimento, è affidato a nuove soluzioni tecnologiche per la green energy, che sta acquisendo sempre più rilevanza in tutti i comparti produttivi e di consumo. In Calabria, in particolare, le tecniche innovative di energie rinnovabili applicabili, per esempio, nei processi agroindustriali, fa-voriscono l'efficienza energetica e il risparmio di risorse naturali del territorio. Da questa esigenza locale, che ri-sponde ad una domanda ben più estesa, è partita l'idea di sviluppare nuove soluzioni di produzione energetica di piccola taglia. Il sistema di micro-cogenerazione presen-tato si inserisce nel filone di ricerca per lo sviluppo di im-pianti alimentati dal Sole basati sulla concentrazione della radiazione solare e sulla simultanea produzione di ener-gia elettrica e di energia termica, per massimizzare il ren-dimento complessivo di generazione solare a parità di superficie occupata. 2. Obiettivi Fuori dell'atmosfera il Sole illumina in media la Terra con circa 1367 W/m 2 di radiazione su un piano perpendi-colare ai raggi solari [1]. Tale valore è conosciuto come costante solare. Non tutta questa energia raggiunge la superficie della Terra a causa dell'atmosfera e dei feno-meni ad essa collegati: riflessione, rifrazione, assorbi-mento e diffusione. La radiazione solare complessiva che giunge al suolo è la somma di tre contributi principali: la radiazione diretta, che è quella che non è assorbita • Abstract This experimental work is focused on a small solar cogeneration system of about 1 kW of electric power and up to 3 kW of thermal power, designed for the decentralised and diffuse production of heat and power with high conversion efficiencies at low power scale. The presented solar system makes use as microcogenerator of an industrial Stirling engine of small size, with an electrical efficiency up to 32%, originally designed for domestic combined heat-power applications in gas boilers. The heat acceptor of the Stirling head has been completely re-engineered for the solar application, together with a solar dish concentrator moved by a suitable two axis tracking system. In one year the average electricity produced is about 185 kWh/m2 and the average thermal energy is around 858 kWh/m2. The resulting annual electrical efficiency is about 9%, but can be improved, and the annual thermal efficiency is about 46%. The collecting surface of the solar dish measures approximately 9.6 m2, about the 50% of the collecting surface for an equivalent non-coge-nerative system.

- by Giulia Fresca
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- Renewable Energy, Energy, Power System, Energy efficiency

A parabolic solar dish concentrator, as the heat source of an organic Rankine cycle (ORC), can be used for power generation. Different types of tubular cavity receivers with different nanofluids can be considered for use in the solar dish collector to improve its efficiency. In the current research, an ORC with three different cavity receivers including hemispherical, cubical, and cylindrical are investigated using three nanofluids: Al 2 O 3 /oil, CuO/oil, and SiO 2 /oil. A numerical model is validated using experimental data. The ORC analysis is done for a constant evaporator pressure of 2.5 MPa, and condenser temperature of 38 • C. Methanol is employed as the ORC's working fluid and a non-regenerative, ideal ORC system with different turbine inlet temperatures is considered. Furthermore, a fixed solar heat transfer fluid flow rate of 60 mL/s and dish diameter of 1.9 m is investigated. Results show that, compared to pure oil, the thermal efficiency of the cavity receivers increases slightly, and the pressure drop increases with the application of nanofluids. Furthermore, results show that the cubical cavity receiver, using oil/Al 2 O 3 nanofluid, is the most efficient choice for application as the investigated solar ORC's heat source.

- by Willem Le Roux
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- Nanofluids, Solar Dish Collector

Concentrated Solar Power (CSP) is quickly becoming a necessity as a result of it being a renewable energy power source, as well as showing potential for high efficiencies. A parabolic dish is an attractive form of CSP, since it can be scaled down and used for off-grid power supply to rural areas. The accuracy of a parabolic dish depends mainly on the parabolic function, specularity and slope error, shadowing and reflectivity. These factors affect the heat flux distribution at the receiver. By decreasing these errors, the collector will experience less energy spillage. A lunar test was done in order to analyse the spillage and flux map of a parabolic dish in its construction phase, using the full moon. The lunar flux map was analysed and compared to a flux map modelled with SolTrace, so that the cause of spillage could be determined. The lunar flux mapping method is cost effective and a simple technique for pinpointing areas in a collector that need improvement.

- by Willem Le Roux
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- Solar Dish Collector

The depletion of fossil fuels is an inevitability which has led to an increased interest into renewable energies. One of the plausible energy replacement fields is alcohol distillation utilising solar collection for the production of fuel. The challenge faced during alcohol distillation using solar collection is predominantly system efficiency and cost. This paper presents the testing and development of a low-cost small-scale dish-mounted solar still. A numerical model was developed and compared with experimental results. Different receiver types as well as direct and indirect heating methods were compared. The temperature of the boiling fluid was measured along with the rate of distillation. It is recommended that a direct heating system with periodic flushing be designed and tested, where the post-distillation boiling fluid is flushed out periodically and replaced with pre-distillation boiling fluid. Assuming 4 hours of sunlight with a DNI above 800 W/m 2 and a system flushing and reinitialising time of 10 minutes, it is predicted that the direct heating system with 1.5 m solar dish diameter can produce 2.6 kg of distilled alcohol.

- by Willem Le Roux and +1
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- Solar Dish Collector

Concentrated solar power presents immense scope for the deployment of small-scale units focusing on diverse applications, including process heat and rural on/off-grid applications. This paper presents the analysis of solar irradiance variation on heat flux and temperature distribution at the dish concentrator receiver. A solar dish concentrator with a 2.8-m aperture diameter and a 0.4-m depth was used for this analysis. The solar ray intersection between a dish concentrator and its receiver, along with the heat flux distribution prediction, was carried out using SolTrace. The effect of flux intensity variation on temperature distribution at the receiver was investigated using COMSOL MULTIPHYSICS. The optical analysis considered 10,000 rays, and 91.65% of them were observed to reach the surface of the receiver. For 1000 W/m 2 of beam solar radiation, a peak heat flux and maximum temperature at the concentrator's focal plane are found to be 32.4 MW/m 2 and 923 K, respectively. The validation had been done using previously reported results in the literature to verify the correctness of the present simulation results. The effect of beam solar radiation variation on heat flux intensity and the temperature distribution revealed that both heat flux and temperature increase with increasing solar radiation, which points out the influence of design and operating conditions. Apart from PillBox and Gaussian distributions, the effect of slope and specularity errors was characterized, suggesting a greater sensitivity to the former than the latter.

Water desalination is the method of saltwater separating into two parts by using various types of energy. This paper offers an experimental work for solar distillation system to the production of drinking water by single slope solar still integrated with a parabolic dish. The result was compared with different solar still designs in the literature. The proposed solar thermal performance of the suggested solar still has been investigated to show its applicability in Iraq, Najaf (32.1N o , 44.19E o) during winter session (Nov., Dec., Jan.) 2018-2019. The assessment based on the effects of operational parameters, including solar irradiance, ambient temperature, wind speed, absorption wall temperature. A copper helical conical coil was used to compare steam condensation generated from the evaporator. The productivity of this study was 11.45 L.day-1 , 8.2 L.day-1 freshwater with and without coil condenser respectively, and average direct solar irradiance was 753.6 W.m-2. Comparison different types of solar stills, especially those that have used as concentrators of solar irradiance, with comparable periods of work time, indicate excellent performance. Also, this system can be considered acceptable because it can provide distilled water from the use of materials available in local markets and low cost, enough to cover the daily needs of water for at least two adults.

- by Mohammed R . Al_qassab
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- Renewable Energy, Distillation columns, Solar Energy, Solar Dish Collector

A parabolic solar dish concentrator, as the heat source of an organic Rankine cycle (ORC), can be used for power generation. Different types of tubular cavity receivers with different nanofluids can be considered for use in the solar dish collector to improve its efficiency. In the current research, an ORC with three different cavity receivers including hemispherical, cubical, and cylindrical are investigated using three nanofluids: Al2O3/oil, CuO/oil, and SiO2/oil. A numerical model is validated using experimental data. The ORC analysis is done for a constant evaporator pressure of 2.5 MPa, and condenser temperature of 38 °C. Methanol is employed as the ORC’s working fluid and a non-regenerative, ideal ORC system with different turbine inlet temperatures is considered. Furthermore, a fixed solar heat transfer fluid flow rate of 60 mL/s and dish diameter of 1.9 m is investigated. Results show that, compared to pure oil, the thermal efficiency of the cavity receivers increases slight...

- by Talal Yusaf
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- Engineering, Nanofluids, Applied Sciences, Solar Dish Collector

Water desalination is the method of saltwater separating into two parts by using various types of energy. This paper offers an experimental work for solar distillation system to the production of drinking water by single slope solar still integrated with a parabolic dish. The result was compared with different solar still designs in the literature. The proposed solar thermal performance of the suggested solar still has been investigated to show its applicability in Iraq, Najaf (32.1N, 44.19E) during winter session (Nov., Dec., Jan.) 2018-2019. The assessment based on the effects of operational parameters, including solar irradiance, ambient temperature, wind speed, absorption wall temperature. A copper helical conical coil was used to compare steam condensation generated from the evaporator. The productivity of this study was 11.45 L.day, 8.2 L.day freshwater with and without coil condenser respectively, and average direct solar irradiance was 753.6 W.m. Comparison different types o...

A small-scale open solar-thermal Brayton cycle using a parabolic dish as the concentrated solar power system is a solution to the problem Southern Africa faces, which is that communities stay too far from the national grid and therefore do not have access to electricity and hot water. This small-scale system will be mobile and offer the ability to produce off-grid electricity and hot water by using concentrated solar power. An open-cavity tubular solar receiver, and the heat losses that occur due to conduction, convection and radiation is investigated. The solar receiver receives concentrated solar energy from a 4.8 m parabolic dish, which then heats compressed air to turn the turbine of a turbocharger, which would power a compressor and an electric generator. The insulated receiver was tested in a solar dish set-up by sending hot compressed air through it. By measuring surface temperatures at specific intervals from inlet to outlet, as well as the inlet and outlet air temperatures, as well as the temperatures on the exterior of the insulation, a thorough heat loss analysis can be done. Testing done without solar exposure in stow position (or an angle of 0°), taking weather conditions into account proved that most of the heat lost at this angle is due to radiation, and on very windy days the convection losses are greater than normal. The receiver analyzed in this paper had a total heat loss rate of 6.3 kW at an average surface temperature of about 950K, with the conduction, radiation and convection heat losses accounting for 17%, 45% and 38% respectively. Assuming the receiver receives about 13 kW of solar energy from the collector, the receiver efficiency is calculated to be approximately 50%.

- by Tamryn Wolff
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- Renewable Energy, Energy efficiency, Solar Energy, Energy Efficiency

A parabolic solar dish concentrator, as the heat source of an organic Rankine cycle (ORC), can be used for power generation. Different types of tubular cavity receivers with different nanofluids can be considered for use in the solar dish collector to improve its efficiency. In the current research, an ORC with three different cavity receivers including hemispherical, cubical, and cylindrical are investigated using three nanofluids: Al2O3/oil, CuO/oil, and SiO2/oil. A numerical model is validated using experimental data. The ORC analysis is done for a constant evaporator pressure of 2.5 MPa, and condenser temperature of 38 °C. Methanol is employed as the ORC’s working fluid and a non-regenerative, ideal ORC system with different turbine inlet temperatures is considered. Furthermore, a fixed solar heat transfer fluid flow rate of 60 mL/s and dish diameter of 1.9 m is investigated. Results show that, compared to pure oil, the thermal efficiency of the cavity receivers increases slight...

- by Gholamhassan Najafi
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- Engineering, Nanofluids, Applied Sciences, Solar Dish Collector

A parabolic solar dish concentrator, as the heat source of an organic Rankine cycle (ORC), can be used for power generation. Different types of tubular cavity receivers with different nanofluids can be considered for use in the solar dish collector to improve its efficiency. In the current research, an ORC with three different cavity receivers including hemispherical, cubical, and cylindrical are investigated using three nanofluids: Al2O3/oil, CuO/oil, and SiO2/oil. A numerical model is validated using experimental data. The ORC analysis is done for a constant evaporator pressure of 2.5 MPa, and condenser temperature of 38 °C. Methanol is employed as the ORC’s working fluid and a non-regenerative, ideal ORC system with different turbine inlet temperatures is considered. Furthermore, a fixed solar heat transfer fluid flow rate of 60 mL/s and dish diameter of 1.9 m is investigated. Results show that, compared to pure oil, the thermal efficiency of the cavity receivers increases slight...

- by Ezzatollah Askari Asli Ardeh
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- Engineering, Nanofluids, Applied Sciences, Solar Dish Collector

Abstract Solar concentrating technologies can produce heat for applications such as solar heating, solar cooling, industrial processes, desalination and electric power generation. For a solar dish collector, various solar receivers and working fluids at different flow rates can be used in different applications. In this work, three different cavity receivers are investigated for application in a solar dish collector using either water or Behran oil. A numerical model is used in the analysis, which is validated with experimental results from a hemispherical cavity receiver using oil as working fluid. The model is applied to compare hemispherical, cylindrical and cubical receivers under the same operating conditions using either water or oil, at a volumetric flow rate of 100 ml/s and solar irradiance of 800 W/m2, in order to determine the most suitable cavity for a specific solar dish. The system is investigated for inlet temperatures ranging from 40 °C to 90 °C with water as working fluid, and from 40 °C to 300 °C with Behran oil as working fluid. Emphasis is placed on the calculation of useful heat production, as well as pressure drop which influences pumping power. The exergetic efficiency criterion and the overall efficiency criterion are used in order to evaluate the useful heat production and the pumping power simultaneously. The high exergetic efficiency of the hemispherical cavity with thermal oil at high temperatures makes this case a promising choice for high-temperature solar dish collector applications. Moreover, water is found to be the best candidate for low-temperature applications since it leads to the higher thermal efficiency with lower pumping power demand.

- by Willem Le Roux
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- Solar Dish Collector, Micro gas turbine, Brayton Cycle