Journal articles: 'Solar conical collector'

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Schneider, F. P., C. E. C. Nogueira, Fernando Toniazzo, S. N. M. Souza, J. A. C. Siqueira, I. L. Nogueira, and D. R. Santos. "Characterization of a Water Heating System Using Solar Collector With Conical Concentrator." Journal of Agricultural Science 10, no. 12 (November 15, 2018): 405. http://dx.doi.org/10.5539/jas.v10n12p405.

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This study aimed to evaluate a solar water heating system for using on residences, using a solar collector with conical concentrator. The principle of light concentration in a solar collector with conical concentrator is the capture and reflection of solar radiation in the center of a tapered concentrator with internal reflective faces. The area of concentration of solar energy is occupied by a receiver with material of high thermal conductivity, properly isolated by transparent surfaces, to form the greenhouse effect, where the thermal energy is transferred to a working fluid. The characterization of the system was done through field tests to determine the efficiency in the water heating. The tests were performed considering different scenarios, which varied according to the heating system (passive and active with different water flow) and solar tracking (manual adjustment and stationary). The results showed that the scenarios with solar tracking presented an average efficiency of 12.63%, which was more efficient than those presented by the fixed orientation, which was 11.44%. Besides that, it was verified that the active solar heating systems were more efficient than the passive ones.

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Vijayan, G., S. Giridharan, and R. Karunakaran. "Investigation of Heat Transfer Performance of Nanofluids on Conical Solar Collector under Dynamic Condition." Advanced Materials Research 984-985 (July 2014): 1125–31. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.1125.

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Heat transfer improvement in solar operated devices is one of the key issues of energy saving and compact designs. Researches in heat transfer have been carried out over the past several decades, culminating in the development of the heat transfer techniques used at present. The use of additives is a technique employed to enhance the heat transfer performance of base fluids. Recently, an innovative material, nanosized particle has been used in suspension in conventional heat transfer fluids that changes the heat transfer characteristic. In this project, an attempt has been made to verify change in heat transfer behavior while using nanofluids. For this purpose, a conical solar collector has been designed, constructed using locally available sheet steel. Polyurethane foam material is used as a insulating liner inside the cone. Thin reflective aluminum sheet is used to focus the solar radiation onto the absorbing surface. The main objective of this paper is to study the heat transfer behavior of Al2O3, Cu2O and ZnO nanofluid and especially Al2O3nanofluid of various concentrations in absorber space of conical solar collector. Experimental study was conducted on different days and the data were recorded. The results obtained show that addition of nanoparticles in the base fluid, improve the heat transfer rate.

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Khalil, Imane, Quinn Pratt, Christopher Spitler, and Daniel Codd. "Modeling a thermoplate conical heat exchanger in a point focus solar thermal collector." International Journal of Heat and Mass Transfer 130 (March 2019): 1–8. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2018.10.041.

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Pavlovic, Sasa, Reyhaneh Loni, Evangelos Bellos, Darko Vasiljević, Gholamhassan Najafi, and Alibakhsh Kasaeian. "Comparative study of spiral and conical cavity receivers for a solar dish collector." Energy Conversion and Management 178 (December 2018): 111–22. http://dx.doi.org/10.1016/j.enconman.2018.10.030.

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Mohammed, Hussein A., Hari B. Vuthaluru, and Shaomin Liu. "Heat transfer augmentation of parabolic trough solar collector receiver's tube using hybrid nanofluids and conical turbulators." Journal of the Taiwan Institute of Chemical Engineers 125 (August 2021): 215–42. http://dx.doi.org/10.1016/j.jtice.2021.06.032.

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Abuşka, Mesut, and Mehmet Bahattin Akgül. "Experimental Study on Thermal Performance of a Novel Solar Air Collector Having Conical Springs on Absorber Plate." Arabian Journal for Science and Engineering 41, no. 11 (May 10, 2016): 4509–16. http://dx.doi.org/10.1007/s13369-016-2177-4.

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Senthil, Ramalingam, Inbaraj Infanta Mary Priya, Mukund Gupta, Chinmaya Rath, and Nilanshu Ghosh. "Experimental Study on Solar Heat Battery using Phase Change Materials for Parabolic Dish Collectors." International Journal of Renewable Energy Development 10, no. 4 (June 26, 2021): 819–25. http://dx.doi.org/10.14710/ijred.2021.38376.

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Energy consumption has increased withthe population increase, and fossil fuel dependency has risen and causing pollutions. Solar energy is suitableto provide society's thermo-electric needs. Thermal energy storage-based concentrated solar receivers are aimed at store heat energy and transportable to the applications. Acavity receiver with two-phase change materials (PCM) is experimentally investigated using a parabolic dish collector to act as the solar heat battery. The selected PCMs are MgCl2.6H2O and KNO3-NaNO3. PCMs are chosen and placed as perthe temperature zones of the receiver. The outdoor test wasconductedto determine the conical receiver's storage performance using cascaded PCMs. The complete melting of PCM attainsat an average receiver surface temperature of 230°C. The complete melting of the PCM in the receiver took around 30 minutes at average radiation around 700 W/m2, and heat stored is approximately 5000 kJ. The estimated number of cavity receivers to be charged on a sunny day is about 10-15 according to the present design and selected PCMs, for later use

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A'laa Taghi Al-Azawi and Ali A. F. Al Hamadani. "The Effect of Different Absorber Configurations On The Exergy and The Energy of Parabolic Solar Dish." Wasit Journal of Engineering Sciences 7, no. 3 (April 11, 2020): 1–13. http://dx.doi.org/10.31185/ejuow.vol7.iss3.133.

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Abstract— The solar energy is the most important type of energy. The parabolic dish solar collector (PDSC) is the best type among other solar collectors because it is always tracking the sun movement. The exergy and the energy performances of a PDS were analyzed experimentally and numerically. The effect of different coil geometries and different mass flow rates of heat transfer fluid (HTF) were investigated. The PDS has parabolic dish and receiver with diameter (1.5) m and (0.2) m respectively. Concentration ratio is 56.25. The parabolic polar dish was supported by a tracking system with two axes. The types of the copper absorber were used which are: (spiral –helical) coil (SHC) and spiral-conical coil (SCC). The results showed that the useful energy and thermal efficiency are varying with solar radiation variation. The useful energy varying between (480-765) W for (SHC), the thermal efficiency varying between (35.2-39.8) % for (SHC). Exergy efficiency varying between (6.9 –8.6) %. It was shown that the higher values of useful energy for (spiral – helical) absorber was 0.1L/min flow rate. REFERENCES 1. T. Taumoefolau , K. Lovegrove ," An Experimental Study of Natural Convection Heat Loss from a Solar Concentrator Cavity Receiver at Varying Orientation. ", Australian National University,, Canberra ACT 0200 AUSTRALIA.2002 2. S. PAITOONSURIKARN and K. LOVEGROVE," On the Study of Convection Loss from Open Cavity Receivers in Solar Paraboloidal Dish Applications ", Australian National University Canberra ACT 0200, AUSTRALIA, pp 154,155,2003 3. Soteris A. Kalogirou*,"Solar thermal collectors and applications", Higher Technical Institute, Progress in Energy and Combustion Science 30 (2004) 231–295, pp237, 240, 241, 2004 4. M. Prakash, S.B. Kedare, J.K. Nayak," Investigations on heat losses from a solar cavity receiver", Department of Energy Science and Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India,2008. 5. Shiva Gorjian1, Barat Ghobadian1, Teymour Tavakkoli Hashjin1, and Ahmad Banak ,"Thermal performance of a Point-focus Solar Steam Generating System ", 21st Annual International Conference on Mechanical Engineering-ISME201 7-9 May, 2013, School of Mechanical Eng., K.N.Toosi University, Tehran, Iran ,1ISME2013-1195,2013 6. Kailash Karunakaran1 Hyacinth J Kennady2 ,"Thermal Analysis of Parabolic Dish Snow Melting Device " ,International Journal for Research in Technological Studies| Vol. 1, Issue 3, February 2014 | ISSN (online): 2348-1439,2014 7. Charles-Alexis Asselineau, Ehsan Abbasi, John Pye "Open cavity receiver geometry influence on radiative losses" Australian National University (ANU), Canberra, ACT 0200 Australia. Solar2014: The 52nd Annual Conference of the Australian Solar Council 2014 8. Vahid Madadi, Touraj Tavakoli and Amir Rahimi First and second thermodynamic law analyses applied to a solar dish collector" DOI 10.1515/jnet-2014-0023 | J. Non-Equilib. Thermodyn. 2014; 39 (4):183–197 9. Yaseen. H. Mahmood , Mayadah K h. Ghaffar " Design of Solar dish concentration by using MATLAB program and Calculation of geometrical concentration parameters and heat transfer" , University of Tikrit , Tikrit , Iraq, Tikrit Journal of Pure Science 20 (4) ISSN: 1813 – 1662, 2015. 10. Vanita Thakkar, Ankush Doshi, Akshaykumar Rana "Performance Analysis Methodology for Parabolic Dish Solar Concentrators for Process Heating Using Thermic Fluid IOSR", Journal of Mechanical and Civil Engineering (IOSR-JMCE) eISSN: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 1 Ver. II (Jan- Feb. 2015), PP 101-114 11. Saša R. pavlovi, Evangelos A. bellos, Velimir P. Stefanovi, Christos Tzivanidis and Zoran M. Stamenkovi "Design, Simulation ,and Optimiztion Of A Solar Dish Collector with spiral coil absorber ", , Nis, Serbia, thermal SCIENCE, Vol. 20, No. 4, pp. 1387-1397 1387,2016 12. Flávia V. Barbosa, João L. Afonso, Filipe B. Rodrigues, and José C. F. Teixeir," Development of a solar concentrator with tracking system", University of Minho,Guimarães, 4800-058, Portugal2016 13. O. López, A. Arenas, and A. Baños"Convective Heat Loss Analysis of a Cavity Receiver for a Solar Concentrator" International Conference on Renewable Energies and Power Quality (ICREPQ’17)Malaga (Spain), 4th to 6th April, 2017 ,ISSN 2172-038 X, No.15 April 2017 RE&PQJ, Vol.1, No.15, April 2017 14. D.R.Rajendran,E.GanapathySundaram,P.Jawahar "Experimental Studies on the Thermal Performance of a Parabolic Dish Solar Receiver with the Heat Transfer Fluids Sic water Nano Fluid and Water", Journal of Thermal Science Vol.26, 15. Muhammad Shoaib, Muhammad , Jameel Kabbir Ali ,Muhammad Usman1, Abdul Hannan " Analysis of thermal performance of parabolic dish collectors having different reflective" ,NFC institute of engineering &fertilizer research ,2018 . 16. Sasa PAVLOVIC, Evangelos BELLOS, Velimir STEFANOVIC ,Christos TZIVANIDIS " EXPERIMENTAL AND NUMERICAL INVESTIGATION OF A SOLAR DISH COLLECTOR WITH SPIRAL ABSORBER" A CTA TECHNICA CORVINIENSIS – Bulletin of Engineering Tome XI [2018] .

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Thirunavukkarasu, V., and M. Cheralathan. "Thermal Performance of Solar Parabolic Dish Concentrator with Hetero-Conical Cavity Receiver." Applied Mechanics and Materials 787 (August 2015): 197–201. http://dx.doi.org/10.4028/www.scientific.net/amm.787.197.

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Concentrated solar collectors have high efficiency as compared to flat plate and evacuated tube solar collectors. Cavity receivers are mainly used on the parabolic dish concentrators and tower type concentrator systems. The heat transfer surfaces of cavity receiver are composed by coiled metal tube. Heat transfer fluid flows in the internal spaces of coiled metal tube, and the external surfaces would absorb the highly concentrated solar energy. This paper explains the thermal performance of parabolic dish concentrator system with hetero-conical cavity receiver. The experimental analysis was done during the month of April 2014 on clear sunny days at Chennai [Latitude: 13.08oN, Longitude: 80.27oE] to study its thermal performance.

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Kribus, A. "Optical Performance of Conical Windows for Concentrated Solar Radiation." Journal of Solar Energy Engineering 116, no. 1 (February 1, 1994): 47–52. http://dx.doi.org/10.1115/1.2930065.

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Radiative energy transfer through a truncated cone window with a back-plane reflector is considered. This geometry is proposed for a high-pressure direct-radiation (volumetric) central solar receiver for use in combined-cycle electricity generation. The transmission and loss characteristics, computed by ray-tracing, are parameterized by the angle of incident radiation relative to the cone axis. The overall performance of the window is an integral of the angle-dependent transmission data, weighted by the actual distribution of input radiation, over all incidence angles. This parameterization provides insight and assists in tailoring of the window geometry to different solar collection methods. Results are presented for several window geometries. Overall window performance is presented for a dish-type distribution of input radiation.

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Imtiaz Hussain, M., Gwi Hyun Lee, and Jun-Tae Kim. "Experimental validation of mathematical models of identical aluminum and stainless steel engineered conical solar collectors." Renewable Energy 112 (November 2017): 44–52. http://dx.doi.org/10.1016/j.renene.2017.05.035.

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Zhang, Zhang, Li, Wu, and Zhang. "Comparison of Bi-Hemispherical and Hemispherical-Conical Configurations for In Situ Measurements of Solar-Induced Chlorophyll Fluorescence." Remote Sensing 11, no. 22 (November 12, 2019): 2642. http://dx.doi.org/10.3390/rs11222642.

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During recent decades, solar-induced chlorophyll fluorescence (SIF) has shown to be a good proxy for gross primary production (GPP), promoting the development of ground-based SIF observation systems and supporting a greater understanding of the relationship between SIF and GPP. However, it is unclear whether such SIF-oriented observation systems built from different materials and of different configurations are able to acquire consistent SIF signals from the same target. In this study, we used four different observation systems to measure the same targets together in order to investigate whether SIF from different systems is comparable. Integration time (IT), reflectance, and SIF retrieved from different systems with hemispherical-conical (hemi-con) and bi-hemispherical (bi-hemi) configurations were also evaluated. A newly built prism system (SIFprism, using prism to collect both solar and target radiation) has the shortest IT and highest signal to noise ratio (SNR). Reflectance collected from the different systems showed small differences, and the diurnal patterns of both red and far-red SIF derived from different systems showed a marginal difference when measuring the homogeneous vegetation canopy (grassland). However, when the target is heterogeneous, e.g., the Epipremnum aureum canopy, the values and diurnal pattern of far-red SIF derived from systems with a bi-hemi configuration were obviously different with those derived from the system with hemi-con configuration. These results demonstrate that different SIF systems are able to acquire consistent SIF for landscapes with a homogeneous canopy. However, SIF retrieved from bi-hemi and hemi-con configurations may be distinctive when the target is a heterogeneous (or discontinuous) canopy due to the different fields of view and viewing geometries. Our findings suggest that the bi-hemi configuration has an advantage to measure heterogeneous canopies due to the large field of view for upwelling sensors being representative for the footprint of the eddy covariance flux measurements.

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Woolf, Nick, and Roger Angel. "Pantheon habitat made from regolith, with a focusing solar reflector." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2188 (November 23, 2020): 20200142. http://dx.doi.org/10.1098/rsta.2020.0142.

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We describe a polar Moon base habitat using direct solar energy for construction, food production and atmospheric revitalization. With a growing area as large as 2000 m 2 , it could provide for 40 or more people. The habitat is built like the ancient Roman Pantheon, a stone structure with a top circular oculus, bringing in focused sunlight that is spread out to crops below. The conical, corbelled structure is built from cast regolith blocks, held in compression despite the large internal atmospheric pressure by a regolith overlayer 20–30 m thick. It is sealed on the inside against leaks with thin plastic. A solar mirror concentrator used initially to cast the building blocks is later used to illuminate the habitat through a small pressure window at the oculus. Three years of robotic preparation of the building blocks does not seem excessive for a habitat which can be expected to last for millennia, as has the Treasury of Atreus made by similar dry-stone construction. One goal of returning to the Moon is to demonstrate the practicality of long-term human habitation off the Earth. The off-axis, paraboloidal reflecting mirror is rotated about the vertical polar axis in order to direct horizontal sunlight downward to a focus. In this way, the heavy materials needed from Earth to build and power the habitat are largely limited to the solar concentrator and regolith moving and moulding equipment. By illuminating with a reflector rather than with electricity, the solar collection area is 20 times smaller than would be needed for PV cells. This article is part of a discussion meeting issue ‘Astronomy from the Moon: the next decades’.

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Alsouyid, Hajer Mohammed, Nuria Ali Elamri, Haifa Mohamed Duzan, Abdunabi Mohamed Abughania, and Ammar Khalifa Aslougi. "Molecular characterization of lternaria solani isolates on tomato plant Lycopersicum esculentum Mill." Journal of Misurata University for Agricultural Sciences, no. 01 (October 6, 2019): 379–400. http://dx.doi.org/10.36602/jmuas.2019.v01.01.29.

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Early blight disease causes severe damage to the foliar part of solanaceous crops including tomato. Fifteen isolates (12 from tomato, 2 from potato, 1 from pepper) were collected from different sources in Tripoli. Field and laboratory studies were conducted to determine cultural behaviour on PDA medium, morphological, pathogenic and molecular variation between isolates tested. Colonies of isolates revealed variation in their cultural behaviour on PDA medium ranging from cottony to appressed growth, with colour ranging between light to dark olivaceous. The pigments released by the isolates changed the medium colour to grey or brown. Morphological studies of the fungal isolates exhibited short conidiophores bearing a single or chains of paired conidia. This study revealed a significant variation in conidial size for the isolates tested ranging from 23.45 to 46.90 x 7.70 to 14.00 µm. Pathogenicity testes on fruits, plants, and detached leaves of tomato indicated a high significant variation between isolates tested ranging from highly to moderate or weak pathogenic. Genetic diversity of A. solani isolates using RAPD-PCR with oligonuclotide primers revealed significant differences in the appearance of polymorphic and monomorphic banding patterns. Three primers (OPA-07, OPA-09, OPJ-09) out of ten were able to determine the genetic fingerprints of tested isolates. Cluster analysis of RAPD-PCR products showed that primer OPA-07 was able to classify the isolates into five groups: group A (TF4,TF7, TL1, TL3), group B (TF1,TF3, TF8, PEF), group C (TF5, TF6, TF9, POL1, POL2), whereas the remaining two isolates TL2 and TF2 were unique in their patterns and were designated as group U1 and U2 respectively. Primer OPA-09 revealed four distinct genetic groups designated as: group A (TF4, TF6, TF7, TF8, TL2), group B (POL1, TL3, TF3), group C (TF5, POL2) and group D (TL1, TF1, TF2, TF9, PEF). However primer OPJ-09 was able to split the isolates tested into four distinct clusters: group A (TF1, TF7, TL3, PEF), group B (TF3, TF8, POL2), group C (TF2, TF6, TF9, TL2) and group D (TF4, TF5). The results of RAPD-PCR demonstrate existence of considerable variation in molecular characteristics of A. solan iisolates. Accordingly these isolates were classified into different groups and unique patterns with no obvious association between the pattern of clustering of the isolates and their host of origin, morphological characteristics and pathogenicity.

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Madadi, Vahid, Touraj Tavakoli, and Amir Rahimi. "First and second thermodynamic law analyses applied to a solar dish collector." Journal of Non-Equilibrium Thermodynamics 39, no. 4 (January 1, 2014). http://dx.doi.org/10.1515/jnet-2014-0023.

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AbstractThe energy and exergy performance of a parabolic dish collector is investigated experimentally and theoretically. The effect of receiver type, inlet temperature and mass flow rate of heat transfer fluid (HTF), receiver temperature, receiver aspect ratio and solar radiation are investigated. To evaluate the effect of the receiver aperture area on the system performance, three aperture diameters are considered. It is deduced that the fully opened receivers have the greatest exergy and thermal efficiency. The cylindrical receiver has greater energy and exergy efficiency than the conical one due to less exergy destruction. It is found that the highest exergy destruction is due to heat transfer between the sun and the receivers and counts for 35 % to 60 % of the total wasted exergy. For three selected receiver aperture diameters, the exergy efficiency is minimum for a specified HTF mass flow rate. High solar radiation allows the system to work at higher HTF inlet temperatures. To use this system in applications that need high temperatures, in cylindrical and conical receivers, the HTF mass flow rates lower than 0.05 and 0.09 kg/s are suggested, respectively. For applications that need higher amounts of energy content, higher HTF mass flow rates than the above mentioned values are recommended.

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Jafar, K. Syed, M. Arulprakasajothi, N. Beemkumar, and K. Elangovan. "Effect of conical strip inserts in a parabolic trough solar collector under turbulent flow." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, August 13, 2019, 1–13. http://dx.doi.org/10.1080/15567036.2019.1650850.

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Subramani, J., P. K. Nagarajan, C. Subramaniyan, and N. Anbuselvan. "Performance studies on solar parabolic dish collector using conical cavity receiver for community heating applications." Materials Today: Proceedings, October 2020. http://dx.doi.org/10.1016/j.matpr.2020.09.062.

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Kopalakrishnaswami, Arjun Singh, and Sendhil Kumar Natarajan. "Comparative study of modified conical cavity receiver with other receivers for solar paraboloidal dish collector system." Environmental Science and Pollution Research, September 3, 2021. http://dx.doi.org/10.1007/s11356-021-16127-z.

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Imtiaz Hussain, M., and Gwi Hyun Lee. "Performance Comparison and Model Validation of a Conical Solar Reflector and a Linear Fresnel Concentrator." Journal of Solar Energy Engineering 138, no. 6 (November 2, 2016). http://dx.doi.org/10.1115/1.4034958.

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Comparative performance assessment and model validation of the linear Fresnel concentrator (LFC) and the conical solar reflector (CSR) systems were performed under identical operating and climatic conditions. This paper analyzes the amount of heat loss by convective heat transfer (natural or forced) from the receiver to ambient air with and without a glass-reinforced plastic sheet enclosure around the collector assembly. The matlab ordinary differential equation (ode) solvers were used for simulation of the transient states. Mathematical models were generated from energy balance equations of the glass cover, absorber pipe, heat transfer fluid, and storage tank for each system. Thermal and optical analyses of the LFC (with and without an enclosure) and CSR systems were carried out by using the measured and calculated results. Satisfactory agreement was found between the experimental data and predicted results. The given models are suitable to simulate the dynamic energy flow across the different components of the LFC and CSR systems.

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Karimov, Kh S., and Zubair Ahmad. "A two-stage solar collector using a non-tracking conical concentrator and a glass lens for PV-TEG hybrid system." Applied Physics A 124, no. 12 (November 30, 2018). http://dx.doi.org/10.1007/s00339-018-2296-8.

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Awasthi, Kuldeep, Desireddy Shashidhar Reddy, and Mohd Kaleem Khan. "A Novel High Concentration Fresnel Lens as a Solar Concentrator." Journal of Solar Energy Engineering 144, no. 1 (August 23, 2021). http://dx.doi.org/10.1115/1.4051975.

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Abstract This paper describes the design methodology for a novel Fresnel lens. The original Fresnel lens is obtained from a plano-convex lens, whose spherical surface is split into a number of divisions (called facets), collapsed onto the flat base. Thus, all the facets of the original Fresnel lens have the same radius as that of the plano-convex lens. The proposed design aims to achieve better ray concentration and reduced spherical aberration than the original Fresnel lens by constructing spherical facets with unequal radii. The centers and radii of facets are constrained so that the ray refracted from the bottom vertex of each facet on one side of the optical axis and the ray refracted from the outer vertex of the corresponding facet on the other side of the optical axis must intersect at the focal plane. The proposed lens design has resulted in a 275% gain in the concentration ratio and a 72.5% reduction in the spherical aberration compared to the original lens of the same aperture diameter and number of facets. The performance of both novel and original Fresnel lenses when used as solar concentrators with a conical coil receiver is evaluated. The novel Fresnel lens led to increased heat gain and resulted in a compact solar collector design.

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Liang, Dawei, Joana Almeida, Bruno D. Tibúrcio, Miguel Catela, Dário Garcia, Hugo Costa, and Cláudia R. Vistas. "Seven-Rod Pumping Approach for the Most Efficient Production of TEM00 Mode Solar Laser Power by a Fresnel Lens." Journal of Solar Energy Engineering 143, no. 6 (June 1, 2021). http://dx.doi.org/10.1115/1.4051223.

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Abstract A seven-rod/seven-TEM00 mode beam Fresnel lens solar laser pumping approach is here proposed. The Fresnel lens with 4.0 m2 collection area was used as the primary solar concentrator to pump seven 2.5 mm diameter, 15 mm length Nd:YAG rods within a conical pump cavity through a secondary fused silica aspheric concentrator. Within the pump cavity, solar pump rays not completely absorbed by one of the seven rods were furtherly absorbed by other rods, ensuring hence a high absorption efficiency and avoiding the serious thermal lensing and thermal stress issues associated with classical large rod solar lasers. Seven individual plane-concave large-mode resonators were adopted to enable a good overlap between solar pump mode and TEM00 laser oscillating mode. By using both zemax® and lascad® software, the maximum total TEM00 mode solar laser power of 54.65 W was numerically calculated by optimizing the radius parameter of the Fresnel lens, the diameter of the laser rod, and the radius of curvature of the laser resonator output mirror. TEM00 mode solar laser collection efficiency of 13.66 W/m2 and solar power-to-TEM00 mode laser power conversion efficiency of 1.44% were calculated, representing substantial enhancements of 4.66 times and 4.38 times, respectively, as compared with previous experimental records of the TEM00 mode solar laser pumped through a Fresnel lens with 0.785 m2 collection area. The feasibility of TEM00 mode solar laser power delivery by hollow-core photonic crystal fibers was finally studied.

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Fejfar, Antonín, Petr Klapetek, Jakub Zlámal, Aliaksei Vetushka, Martin Ledinský, and Jan Kočka. "Microscopic Characterizations of Nanostructured Silicon Thin Films for Solar Cells." MRS Proceedings 1321 (2011). http://dx.doi.org/10.1557/opl.2011.1097.

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ABSTRACTMicroscopic characterization of mixed phase silicon thin films by conductive atomic force microscopy (C-AFM) was used to study the structure composed of conical microcrystalline grains dispersed in amorphous matrix. C-AFM experiments were interpreted using simulations of electric field and current distributions. Density of absorbed optical power was calculated by numerically solving the Maxwell equations. The goal of this study is to combine both models in order to simulate local photoconductivity for understanding the charge photogeneration and collection in nanostructured solar cells.

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Journal articles on the topic 'Solar conical collector'

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