A Comprehensive Review of Thermal Performance Enhancement Strategies in Solar Air Collectors
DOI:
https://doi.org/10.52262/3x6q2656Keywords:
Solar air collectors, Thermal performance enhancement, Flat-plate collectors, Evacuated tube systems, Concentrated solar collectorsAbstract
A Solar Air Collector (SAC) constitutes a fundamental component of solar-thermal air systems, functioning by absorbing solar radiation and converting it into thermal energy to heat air as the working fluid. This study provides a comprehensive and structured review of the three primary configurations of SACs: flat-plate SACs (FPSAC), evacuated tube SACs (EVTSAC), and concentrated SACs. The development of SACs has consistently prioritized high thermal efficiency, minimal heat losses, and structural simplicity. This paper synthesizes various enhancement strategies employed to improve SAC performance, including advanced surface modification techniques, novel absorber materials, optimized airflow configurations, embedded heat transfer elements, and hybrid systems incorporating energy storage or photovoltaic/thermal (PV/T) integration. Comparative performance assessments among SAC variants reveal that FPSACs employing grooved or half-conical absorbers achieve a performance evaluation factor of approximately 2. EVTSACs integrated with micro-heat pipe arrays can reach thermal efficiencies up to 73%. Meanwhile, concentrated SACs—particularly those employing linear concentration and open Brayton cycles—can attain outlet air temperatures up to 350 °C, with corresponding thermal efficiencies of around 75%. The findings underscore the importance of integrating high-performance heat transfer components in future SAC design optimizations. The study concludes with research directions to address current limitations and explore emerging technologies.
References
Sarıdemir S, Etem Gürel A, A˘ gbulut Ü, Bakan F. Investigating the role of fuel injection pressure change on performance characteristics of a DI-CI engine fuelled with methyl ester. Fuel 2020;271:117634. https://doi.org/10.1016/j. fuel.2020.117634.
Zeng K, Gauthier D, Minh DP, Weiss-Hortala E, Nzihou A, Flamant G. Characterization of solar fuels obtained from beech wood solar pyrolysis. Fuel 2017;188:285–93. https://doi.org/10.1016/j.fuel.2016.10.036.
BP p.l.c.. Statistical review of world energy. 2021.
International Energy Agency. World energy outlook 2021. 2021.
BP Outlook. BP energy outlook 2019 edition. The energy outlook explores the forces shaping the global energy transition out to 2040 and the key uncertainties surrounding that. BP Energy Outlook 2019 2019.
Hannah Ritchie. Energy mix – our world in data. Our world in data 2020. https:// ourworldindata.org/energy-mix [accessed December 16, 2020].
Zhu T, Diao Y, Zhao Y, Deng Y. Experimental study on the thermal performance and pressure drop of a solar air collector based on flat micro-heat pipe arrays. Energy Convers Manage 2015;94:447–57. https://doi.org/10.1016/j. enconman.2015.01.052.
Razak AA, Majid ZAA, Azmi WH, Ruslan MH, Choobchian S, Najafi G, et al. Review on matrix thermal absorber designs for solar air collector. Renew Sustain Energy Rev 2016;64:682–93. https://doi.org/10.1016/j.rser.2016.06.015. [15] Rajarajeswari K, Sreekumar A. Matrix solar air heaters – a review. Renew Sustain Energy Rev 2016;57:704–12. https://doi.org/10.1016/j.rser.2015.12.127. [16] Chamoli S, Chauhan R, Thakur NS, Saini JS. A review of the performance of double pass solar air heater. Renew Sustain Energy Rev 2012;16:481–92. https:// doi.org/10.1016/j.rser.2011.08.012.
Hu J, Zhang G. Performance improvement of solar air collector based on airflow reorganization: a review. Appl Therm Eng 2019;155:592–611. https://doi.org/ 10.1016/j.applthermaleng.2019.04.021.
Ravi RK, Saini RP. A review on different techniques used for performance enhancement of double pass solar air heaters. Renew Sustain Energy Rev 2016; 56:941–52. https://doi.org/10.1016/j.rser.2015.12.004.
Singh S, Dhiman P. Thermal performance of double pass packed bed solar air heaters – a comprehensive review. Renew Sustain Energy Rev 2016;53:1010–31. https://doi.org/10.1016/j.rser.2015.09.058.
Chauhan R, Singh T, Thakur NS, Kumar N, Kumar R, Kumar A. Heat transfer augmentation in solar thermal collectors using impinging air jets: a comprehensive review. Renew Sustain Energy Rev 2018;82:3179–90. https://doi. org/10.1016/j.rser.2017.10.025.
Alkilani MM, Sopian K, Alghoul MA, Sohif M, Ruslan MH. Review of solar air collectors with thermal storage units. Renew Sustain Energy Rev 2011;15: 1476–90. https://doi.org/10.1016/j.rser.2010.10.019.
Vengadesan E, Senthil R. A review on recent developments in thermal performance enhancement methods of flat plate solar air collector. Renew Sustain Energy Rev 2020;134:110315. https://doi.org/10.1016/j.rser.2020.110315.
Sharma SK, Kalamkar VR. Thermo-hydraulic performance analysis of solar air heaters having artificial roughness – a review. Renew Sustain Energy Rev 2015; 41:413–35. https://doi.org/10.1016/j.rser.2014.08.051.
Singh Bisht V, Kumar Patil A, Gupta A. Review and performance evaluation of roughened solar air heaters. Renew Sustain Energy Rev 2018;81:954–77. https:// doi.org/10.1016/j.rser.2017.08.036.
Alam T, Saini RP, Saini JS. Heat and flow characteristics of air heater ducts provided with turbulators – a review. Renew Sustain Energy Rev 2014;31: 289–304. https://doi.org/10.1016/j.rser.2013.11.050.
Gawande VB, Dhoble AS, Zodpe DB, Chamoli S. A review of CFD methodology used in literature for predicting thermo-hydraulic performance of a roughened solar air heater. Renew Sustain Energy Rev 2016;54:550–605. https://doi.org/ 10.1016/j.rser.2015.10.025.
Saxena A, Varun E-S. A thermodynamic review of solar air heaters. Renew Sustain Energy Rev 2015;43:863–90. https://doi.org/10.1016/j.rser.2014.11.059. [28] Kabeel AE, Hamed MH, Omara ZM, Kandeal AW. Solar air heaters: design configurations, improvement methods and applications – a detailed review. Renew Sustain Energy Rev 2017;70:1189–206. https://doi.org/10.1016/j. rser.2016.12.021.
Suman S, Khan MK, Pathak M. Performance enhancement of solar collectors – a review. Renew Sustain Energy Rev 2015;49:192–210. https://doi.org/10.1016/j. rser.2015.04.087.
Fudholi A, Sopian K. A review of solar air flat plate collector for drying application. Renewable and Sustainable Energy Reviews 2019. https://doi.org/ 10.1016/j.rser.2018.12.032.
Arunkumar HS, Vasudeva Karanth K, Kumar S. Review on the design modifications of a solar air heater for improvement in the thermal performance. Sustain Energy Technol Assess 2020;39:100685. https://doi.org/10.1016/j. seta.2020.100685.
Nees Jan van Eck LW. VOSviewer 2020.
American Society of Heating. Refrigerating and Air-conditioning engineers Inc [ASHRAE]. ASHRAE, Standard 93-2010. 2010.
Cort´ es A, Piacentini R. Improvement of the efficiency of a bare solar collector by means of turbulence promoters. Appl Energy 1990;36:253–61. https://doi.org/ 10.1016/0306-2619(90)90001-T.
Altfeld K, Leiner W, Fiebig M. Second law optimization of flat-plate solar air heaters Part I: the concept of net exergy flow and the modeling of solar air heaters. Sol Energy 1988;41:127–32. https://doi.org/10.1016/0038-092X(88) 90128-4.
Gupta MK, Kaushik SC. Performance evaluation of solar air heater for various artificial roughness geometries based on energy, effective and exergy efficiencies. Renew Energy 2009;34:465–76. https://doi.org/10.1016/j.renene.2008.06.001.
Tiwari GN, Tiwari A, Shyam. In: Solar flat-plate air collectors. Singapore: Springer; 2016. p. 369–416. https://doi.org/10.1007/978-981-10-0807-8_9.
Choudhury C, Chauhan PM, Garg HP. Design curves for conventional solar air heaters. Renew Energy 1995;6:739–49. https://doi.org/10.1016/0960-1481(95) 00007-7.
Kumar R, Rosen MA. A critical review of photovoltaic – thermal solar collectors for air heating. Appl Energy 2011;88:3603–14. https://doi.org/10.1016/j. apenergy.2011.04.044.
Ong KS. Thermal performance of solar air heaters – experimental correlation. Sol Energy 1995;55:209–20. https://doi.org/10.1016/0038-092X(95)00027-O.
Gao W, Lin W, Lu E. Review on research progress of solar air heaters. New Energy 1995;17:1–8.
Naphon P. On the performance and entropy generation of the double-pass solar air heater with longitudinal fins. Renew Energy 2005;30:1345–57. https://doi. org/10.1016/j.renene.2004.10.014.
Yeh HM, Ho CD. Effect of external recycle on the performances of flat-plate solar air heaters with internal fins attached. Renew Energy 2009;34:1340–7. https:// doi.org/10.1016/j.renene.2008.09.005.
Ramadan MRI, El-Sebaii AA, Aboul-Enein S, El-Bialy E. Thermal performance of a packed bed double-pass solar air heater. Energy 2007;32:1524–35. https://doi. org/10.1016/j.energy.2006.09.019.
El-Sebaii AA, Aboul-Enein S, Ramadan MRI, El-Bialy E. Year round performance of double pass solar air heater with packed bed. Energy Convers Manage 2007;48: 990–1003. https://doi.org/10.1016/j.enconman.2006.08.010.
Sopian K, Supranto Daud WRW, Othman MY, Yatim B. Thermal performance of the double-pass solar collector with and without porous media. Renew. Energy 1999;18:557–64. https://doi.org/10.1016/S0960-1481(99)00007-5.
Ho CD, Yeh HM, Wang RC. Heat-transfer enhancement in double-pass flat-plate solar air heaters with recycle. Energy 2005;30:2796–817. https://doi.org/ 10.1016/j.energy.2005.01.006.
Naphon P. Effect of porous media on the performance of the double-pass flat plate solar air heater. Int Commun Heat Mass Transfer 2005;32:140–50. https://doi. org/10.1016/j.icheatmasstransfer.2004.11.001.
Yassien HNS, Alomar OR, Salih MMM. Performance analysis of triple-pass solar air heater system: effects of adding a net of tubes below absorber surface. Sol Energy 2020;207:813–24. https://doi.org/10.1016/j.solener.2020.07.041.
Khanlari A, S¨ ozen A, Afshari F, S ¸irin C, Tuncer AD, Gungor A. Drying municipal sewage sludge with v-groove triple-pass and quadruple-pass solar air heaters along with testing of a solar absorber drying chamber. Sci Total Environ 2020; 709:136198. https://doi.org/10.1016/j.scitotenv.2019.136198.
Kareem MW, Habib K, Ruslan MH, Baran B. Thermal performance study of a multi-pass solar air heating collector system for drying of Roselle (Hibiscus sabdariffa). Renew Energy 2017;113:281–92. https://doi.org/10.1016/j.
Kareem MW, Habib K, Pasha AA, Irshad K, Afolabi LO, Saha BB. Experimental study of multi-pass solar air thermal collector system assisted with sensible energy-storing matrix. Energy 2022;245:123153. https://doi.org/10.1016/J. ENERGY.2022.123153.
Hollick JC PR. Method and apparatus for heating ventilation air for a building. 4,934,338, 1990.
Kumar A, Kumar S, Nagar U, Yadav A. Experimental study of thermal performance of one-ended evacuated tubes for producing hot air. J Sol Energy 2013;2013:1–6. https://doi.org/10.1155/2013/524715.
Lamnatou C, Papanicolaou E, Belessiotis V, Kyriakis N. Experimental investigation and thermodynamic performance analysis of a solar dryer using an evacuated-tube air collector. Appl Energy 2012;94:232–43. https://doi.org/ 10.1016/j.apenergy.2012.01.025.
Papanicolaou E, Belessiotis V, Li X, Wang Z. Study of the thermal performance and air-flow features of a solar air heater with evacuated tubes. In: Proceedings of ISES world congress 2007 (Vol. I–Vol. V). Berlin, Heidelberg: Springer Berlin Heidelberg; 2008. p. 627–33. https://doi.org/10.1007/978-3-540-75997-3_116.
Xu L, Wang Z, Yuan G, Li X, Ruan Y. A new dynamic test method for thermal performance of all-glass evacuated solar air collectors 2012;86:1222–31. 10.1016/j.solener.2012.01.015.
Li H, Dai YJ, Li Y, La D, Wang RZ. Case study of a two-stage rotary desiccant cooling/heating system driven by evacuated glass tube solar air collectors. Energy Build 2012;47:107–12. https://doi.org/10.1016/j.enbuild.2011.11.035.
Paradis PL, Rousse DR, Hall´ e S, Lamarche L, Quesada G. Thermal modeling of evacuated tube solar air collectors. Sol Energy 2015;115:708–21. https://doi.org/ 10.1016/j.solener.2015.03.040.
Afshari F, S¨ ozen A, Khanlari A, Tuncer AD, S ¸irin C. Effect of turbulator modifications on the thermal performance of cost-effective alternative solar air heater. Renew Energy 2020;158:297–310. https://doi.org/10.1016/j. renene.2020.05.148.
Singh I, Vardhan S. Energy, exergy, environmental and economic (4E) analysis of evacuated tube solar collector with helical coils. Journal of Mechanical Science and Technology 36 2022. https://doi.org/10.1007/s12206-022-1041-6.
Singh I, Vardhan S. Experimental investigation of an evacuated tube collector solar air heater with helical inserts. Renew Energy 2021;163:1963–72. https:// doi.org/10.1016/j.renene.2020.10.114.
Yuan Y, Li Y, Dai Y, Wang R. Experimental study on thermal performance of evacuated tubular solar air collector with inserted tubes. Taiyangneng Xuebao/ Acta Energiae Solaris Sinica 2010;31:1429–33.
Wahlquist S, Hansel J, Sabharwall P, Ali A. A critical review of heat pipe experiments in nuclear energy applications 2022. 10.1080/ 00295639.2022.2082230.
He W, Zhang J, Li H, Liu S, Wang Y, Lv B, et al. Optimal thermal management of server cooling system based cooling tower under different ambient temperatures. Appl Therm Eng 2022:207. https://doi.org/10.1016/j. applthermaleng.2022.118176.
Kabeel AE, Khairat Dawood MM, Shehata AI. Augmentation of thermal efficiency of the glass evacuated solar tube collector with coaxial heat pipe with different refrigerants and filling ratio. Energy Convers Manage 2017;138:286–98. https:// doi.org/10.1016/j.enconman.2017.01.048.
Zhu T-T, Zhao Y-H, Diao Y-H, Li F-F, Quan Z-H. Experimental investigation and performance evaluation of a vacuum tube solar air collector based on micro heat pipe arrays. J Clean Prod 2017:142. https://doi.org/10.1016/j. jclepro.2016.10.116.
Wang T, Diao Y, Zhao Y, Liang L, Wang Z, Chen C. A comparative experimental investigation on thermal performance for two types of vacuum tube solar air collectors based on flat micro-heat pipe arrays. Sol Energy 2020;201:508–22.
Wang T, Zhao Y, Diao Y, Ren R, Wang Z. Performance of a new type of solar air collector with transparent-vacuum glass tube based on micro-heat pipe arrays. Energy 2019;177:16–28. https://doi.org/10.1016/j.energy.2019.04.059.
Wang Z, Diao Y, Zhao Y, Chen C, Liang L, Wang T. Thermal performance of integrated collector storage solar air heater with evacuated tube and lap joint- type flat micro-heat pipe arrays. Appl Energy 2020;261:114466. https://doi.org/ 10.1016/j.apenergy.2019.114466.
Türk Toǧrul I, Pehlivan D. The performance of a solar air heater with conical concentrator under forced convection. Int J Therm Sci 2003;42:571–81. https:// doi.org/10.1016/S1290-0729(03)00023-1.
Karimi R, Gheinani TT, Madadi AV. Coupling of a parabolic solar dish collector to f inned-tube heat exchangers for hot air production: an experimental and theoretical study. Sol Energy 2019;187:199–211. https://doi.org/10.1016/j. solener.2019.05.050.
Pramuang S, Exell RHB. Transient test of a solar air heater with a compound parabolic concentrator. Renew Energy 2005;30:715–28. https://doi.org/ 10.1016/j.renene.2004.01.013.
Zhu TT, Diao YH, Zhao YH, Li FF. Thermal performance of a new CPC solar air collector with flat micro-heat pipe arrays. Appl Therm Eng 2016;98:1201–13. https://doi.org/10.1016/j.applthermaleng.2016.01.033.
Li X, Dai YJ, Li Y, Wang RZ. Performance investigation on a novel single-pass evacuated tube with a symmetrical compound parabolic concentrator. Sol Energy 2013;98:275–89. https://doi.org/10.1016/j.solener.2013.10.015.
Wang PY, Li SF, Liu ZH. Collecting performance of an evacuated tubular solar high-temperature air heater with concentric tube heat exchanger. Energy Convers Manage 2015;106:1166–73. https://doi.org/10.1016/j.enconman.2015.10.058.
Liu Z, Hu R, Lu L, Zhao F, Xiao H. Thermal performance of an open thermosyphon using nanofluid for evacuated tubular high temperature air solar collector. Energy Convers Manage 2013;73:135–43. https://doi.org/10.1016/j. enconman.2013.04.010.
Zhao Z, Bai F, Zhang X, Wang Z. Experimental study of pin finned receiver tubes for a parabolic trough solar air collector. Sol Energy 2020;207:91–102. https:// doi.org/10.1016/j.solener.2020.06.070.
Famiglietti A, Lecuona-neumann A, Nogueira J, Rahjoo M. Direct solar production of medium temperature hot air for industrial applications in linear concentrating solar collectors using an open Brayton cycle. Viability analysis. Appl Therm Eng 2020;169:114914. https://doi.org/10.1016/j. applthermaleng.2020.114914.
Bakry AI, El-Samadouny YAF, El-Agouz SA, Alshrombably AM, Abdelfatah KS, Said MA. Performance of the one-ended evacuated tubes as medium temperature solar air heaters at low flow rates. Sustain Energy Technol Assess 2018;30: 174–82. https://doi.org/10.1016/j.seta.2018.10.002.
Chaurasiya PK, Rajak U, Singh SK, Nath Verma T, Sharma VK, Kumar A, et al. A review of techniques for increasing the productivity of passive solar stills. Sustain Energy Technol Assess 2022;52:102033. https://doi.org/10.1016/J. SETA.2022.102033.
Jin R, Zheng H, Ma X, Zhao Y. Performance investigation of integrated concentrating solar air heater with curved Fresnel lens as the cover. Energy 2020; 194:116808. https://doi.org/10.1016/j.energy.2019.116808.
Kasperski J, Nem´ s M. Investigation of thermo-hydraulic performance of concentrated solar air-heater with internal multiple-fin array. Appl Therm Eng 2013;58:411–9. https://doi.org/10.1016/j.applthermaleng.2013.04.018.
Wang PY, Guan HY, Liu ZH, Wang GS, Zhao F, Xiao HS. High temperature collecting performance of a new all-glass evacuated tubular solar air heater with U-shaped tube heat exchanger. Energy Convers Manage 2014;77:315–23. https:// doi.org/10.1016/j.enconman.2013.08.019.
Hassan H, Abo-Elfadl S. Experimental study on the performance of double pass and two inlet ports solar air heater (SAH) at different configurations of the absorber plate. Renew Energy 2018;116:728–40. https://doi.org/10.1016/j. renene.2017.09.047.
MesgarPour M, Heydari A, Wongwises S. Geometry optimization of double pass solar air heater with helical flow path. Sol Energy 2021;213:67–80. https://doi. org/10.1016/j.solener.2020.11.015.
Abo-Elfadl S, Yousef MS, Hassan H. Energy, exergy, and enviroeconomic assessment of double and single pass solar air heaters having a new design absorber. Process Saf Environ Prot 2021;149:451–64. https://doi.org/10.1016/j. psep.2020.11.020.
Zhu T, Diao Y, Zhao Y, Ma C. Performance evaluation of a novel flat-plate solar air collector with micro-heat pipe arrays (MHPA). Appl Therm Eng 2017;118: 1–16. https://doi.org/10.1016/j.applthermaleng.2017.02.076.
Saini RP, Saini JS. Heat transfer and friction factor correlations for artificially roughened ducts with expanded metal mesh as roughness element. Int J Heat Mass Transf 1997;40:973–86. https://doi.org/10.1016/0017-9310(96)00019-1.
Verma SK, Prasad BN. Investigation for the optimal thermohydraulic performance of artificially roughened solar air heaters. Renew Energy 2000;20:19–36. https:// doi.org/10.1016/S0960-1481(99)00081-6.
Ebrahim Momin AM, Saini JS, Solanki SC. Heat transfer and friction in solar air heater duct with V-shaped rib roughness on absorber plate. Int J Heat Mass Transf 2002;45:3383–96. https://doi.org/10.1016/S0017-9310(02)00046-7.
Karim MA, Hawlader MNA. Performance investigation of flat plate, v-corrugated and finned air collectors. Energy 2006;31:452–70. https://doi.org/10.1016/j. energy.2005.03.007.
Bhagoria JL, Saini JS, Solanki SC. Heat transfer coefficient and friction factor correlations for rectangular solar air heater duct having transverse wedge shaped rib roughness on the absorber plate. Renew Energy 2002;25:341–69. https://doi. org/10.1016/S0960-1481(01)00057-X.
. Al-damook A. Experimental evaluation of an unglazed solar air collector for building space heating in Iraq. Renewable energy 2017. Vol112: 498-509.
Martinez RG, Goikolea BA, Paya IG, Bonnamy P, Raji S and Lopez J. Performance assessment of an unglazed solar thermal collector for envelope retrofitting. Energy procedia 2017. 115: 361-368.
Shahsavar A and Ameri M. Experimental investigation and modelling of a direct- coupled PV/T air collector. Solar energy 2010. 84: 1938-1958.
Kumar R and Rosen MA. Performance evaluation of a double pass PV/T solar air heater with and without fins. Applied thermal engineering 2011.31: 1402-1410.
Kim JH and Kim JT. Comparison of electrical and thermal performance of glazed and unglazed PVT collectors. International journal of photoenergy 2012. Article id- 957847.
Tamboli A, Dambhare S and Patil R. Thermal performance analysis of solar flat plate collector incorporated with latent thermal energy storage system (PCM). International engineering journal for research & development. Vol. 4. Issue 7.
. Arun KR, Srinivas M, Saleel CA and Jayaraj S. Influence of the location of discrete macro-encapsulated thermal energy storage on the performance of a double pass solar plate collector system. Renewable energy 2020, 146: 675-686.
. Vaziri R, Ikan M and Egelioglu F. Experimental performance of perforated glazed solar air heaters and unglazed transpired solar air heater. Solar energy 2015. 119: 251-260.
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