تأثیر فاصلۀ هوایی بین دو پوشش شیشه‌ای بر عملکرد هواگرم‌کن‌های صفحه‌ای خورشیدی

نوع مقاله : مقاله پژوهشی

نویسندگان

بخش مهندسی مکانیک، دانشکده فنی و مهندسی، دانشگاه شهید باهنر کرمان، ایران.

چکیده

با توجه به اهمیت روزافزونِ استفاده از انرژی‌های پاک و تجدیدپذیر، یکی از ساده‌ترین مکانیزم‌های تبدیل انرژی تابشی خورشید به انرژی حرارتی، در مقیاس غیرنیروگاهی، استفاده از هوا‌گرم‌کن‌های خورشیدی است که همواره به عنوان ایده‌ای جذاب برای پژوهشگران مطرح بوده است. از این رو، پژوهش حاضر، به مطالعۀ تأثیر فاصلۀ هوایی بر عملکرد هواگرم‌کن‌های صفحه‌ای خورشیدی با دو پوشش شیشه‌ای، از طریق شبیه‌سازی‌های عددی، می‌پردازد. مطالعه‌ای که مشابه آن در مراجع تحقیقاتی مختلف تاکنون گزارش نشده است. بدین منظور، معادلات حاکم بر جریان جابجایی اجباریِ هوای عبوری از داخل کانال هواگرم‌کن و همچنین جریان جابجایی طبیعی در فاصلۀ هوایی بین دو پوشش شیشه‌ای به دلیل وجود نیروی شناوری، با بکارگیری روش المان محدود و استفاده از نرم‌افزار کامسول، حلّ عددی شده‌اند. به‌علاوه، به منظور تعیین میدان دما در اجزای جامدِ هواگرم‌کن، شامل شیشه، صفحۀ جاذب و لایۀ عایق، حل معادلات هدایت حرارتی هم‌زمان با معادلات جریان صورت گرفته است. صحت شبیه‌سازی‌های عددیِ انجام‌شده در این پژوهش، از طریق مقایسه با یافته‌های عددی و تجربیِ پژوهش‌های پیشین مورد ارزیابی قرار گرفته، که سازگاری قابل قبولی در این خصوص به دست آمده است. نتایج حاصل بیانگر تأثیر مثبت حضور لایه هوای بین دو شیشه بر عملکرد هواگرم‌کن‌های صفحه‌ای خورشیدی بوده، به‌طوری‌که با تغییر دبی جریان هوا از 2 تا 14 گرم بر ثانیه عملکرد این نوع از هواگرم‌کن‌ها در شار تابشی 1000 وات بر مترمربع در مقایسه با مدل ساده و بدون فاصلۀ هوایی افزایش راندمانی در حدود 4 تا 6 درصد را نشان داده است. همچنین، در شرایط دبی جریان ...

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Air Gap between two Glass Covers on the Performance of Plane Solar Air Heaters

نویسندگان [English]

  • Omid Deymi
  • Seyyed Abdolreza Gandjalikhan-nassab
Department of Mechanical Engineering, School of Engineering, Shahid Bahonar University of Kerman, Iran.
چکیده [English]

Due to the increasing importance of using clean and renewable energies, one of the simplest mechanisms for converting solar radiant energy into thermal energy, on non-industrial applications, is the use of solar air heaters, which has always been an attractive idea for researchers. Therefore, the present study investigates the effect of air gap on the performance of plane solar air heaters with two glass covers by means of numerical simulations. A similar study has not been yet reported in various research resources. For this purpose, the equations governing the forced convection flow of air passing through the heater duct and also the natural convection flow caused by the buoyancy force in the air gap between two glass covers are numerically solved by applying the finite element method and using COMSOL Multiphysics software. In addition, in order to determine the temperature field in the solid elements of the air heater (including glass cover, absorber plate and insulation layer), conduction heat transfer equations are simultaneously solved with the flow equations. The accuracy of the numerical simulations performed in this research has been evaluated by comparing those with the theoretical and experimental findings of previous researches, and an acceptable consistency and agreement has been obtained in this regard. The results demonstrate the desired effect of the presence of air gap between the two covers on the performance of plane solar air heaters, such that changing the air flow rate from 2 to 14 g/s, the performance of this type of air heaters ...

کلیدواژه‌ها [English]

  • Solar radiation
  • Plane Air Heater
  • Natural convection
  • Forced convection
  • Thermal performance
  1. Waqas, A., and Kumar, S. "Phase Change Material (PCM)-based Solar Air Heating System for Residential Space Heating in Winter", International Journal of Green Energy, Vol. 10, No. 4, Pp. 402-426, (2013).
  2. Al-damook, A., and Khalil, W.H. "Experimental Evaluation of an Unglazed Solar Air Collector for Building Space Heating in Iraq", Renewable Energy, Vol. 112, Pp. 498-509, (2017).
  3. Gandjalikhan-nassab, S. A., and Moeinaddini, M., "Performance Augmentation of Solar Air Heater for Space Heating Using a Flexible Flapping Guide Winglet", Iranian (Iranica) Journal of Energy & Environment, Vol. 12, No. 2, Pp. 161-172, (2021).
  4. Sharma, A., and Sharma, N., "Construction and Performance Analysis of an Indirect Solar Dryer Integrated with Solar Air Heater", Procedia Engineering, Vol. 38, Pp. 3260-3269, (2012).
  5. Khama, R., Aissani, F., and Alkama, R., "Design and Performance Testing of an Industrial-Scale Indirect Solar Dryer", Journal of Engineering Science and Technology, Vol. 11, No. 9, Pp. 1263-1281, (2016).
  6. Baniasadi, E., Ranjbar, S., and Boostani-pour, O., "Experimental Investigation of the Performance of a Mixed-Mode Solar Dryer with Thermal Energy Storage", Renewable Energy, Vol. 112, Pp. 143-150, (2017).
  7. Rezaei, M., Sefid, M., Almutairi, K., Mostafaei-pour, A., Ao, H.X., Hosseini Dehshiri, S.J., Chowdhury, S., and Techato, K., "Investigating Performance of a New Design of Forced Convection Solar Dryer", Sustainable Energy Technologies and Assessments, Vol. 50, P. 101863, (2022).
  8. Mei, L., Infield, D., Eicker, U., Loveday, D., and Fux, V., "Cooling Potential of Ventilated PV Façade and Solar Air Heaters Combined with a Desiccant Cooling Machine", Renewable Energy, Vol. 31, No. 8, Pp. 1265-1278, (2006).
  9. Hatami, Z., Saidi, M.H., Mohammadian, M., and Aghanajafi, C., "Optimization of Solar Collector Surface in Solar Desiccant Wheel Cycle", Energy and Buildings, Vol. 45, Pp. 197-201, (2012).
  10. Fan, W., Kokogiannakis, G., and Ma, Z., "Integrative Modelling and Optimisation of a Desiccant Cooling System Coupled with a Photovoltaic Thermal-Solar Air Heater", Solar Energy, Vol. 193, Pp. 929-947, (2019).
  11. Alta, D., Bilgili, E., Ertekin, C., and Yaldiz, O., "Experimental Investigation of Three Different Solar Air Heaters: Energy and Exergy Analyses", Applied Energy, Vol. 87, No. 10, Pp. 2953-2973, (2010).
  12. Mzad, H., Otmani, A., Haouam, A., Łopata, S., and Ocłoń, P., "Tilt Optimization of a Double-Glazed Air Solar Collector Prototype", XI International Conference on Computational Heat, Mass and Momentum Transfer, In MATEC Web of Conferences, Vol. 240, No. 04006, (2018).
  13. Chabane, F., Noureddine, M., and Brima, A., "Experimental Study of Thermal Efficiency of a Solar Air Heater with an Irregularity Element on Absorber Plate", International Journal of Heat and Technology, Vol. 36, No. 3, Pp. 855-860, (2018).
  14. Zukowski, M., "Experimental Investigations of Thermal and Flow Characteristics of a Novel Microjet Air Solar Heater", Applied Energy, Vol. 142, Pp. 10-20, (2015).
  15. Gao, W., Lin, W., and Lu, E., "Numerical Study on Natural Convection inside the Channel between the Flat-Plate Cover and Sine-Wave Absorber of a Cross-Corrugated Solar Air Heater", Energy Conversion and Management, Vol. 41, No. 2, Pp. 145-151, (2000).
  16. Gao, W., Lin, W., Liu, T., and Xia, C., "Analytical and Experimental Studies on the Thermal Performance of Cross-Corrugated and Flat-Plate Solar Air Heaters", Applied Energy, Vol. 84, No. 4, Pp. 425-441, (2007).
  17. Siddique, W., Raheem, A., Aqeel, M., Qayyum, S., Salamen, T., Waheed, K., and Qureshi, K., "Evaluation of Thermal Performance Factor for Solar Air Heaters with Artificially Roughened Channels", Archive of Mechanical Engineering, Vol. 68, No. 2, Pp. 195-225, (2021).
  18. Kulkarni, K., Afzal, A., and Kim, K.Y., "Multi-Objective Optimization of Solar Air Heater with Obstacles on Absorber Plate", Solar Energy, Vol. 114, Pp. 364-377, (2015).
  19. Hosseini, S.S., Ramiar, A., and Ranjbar, A. A., "Numerical Investigation of Natural Convection Solar Air Heater with Different Fins Shape", Renewable Energy, Vol. 117, Pp. 488-500, (2017).
  20. Singh, S., and Negi, B. S., "Numerical Thermal Performance Investigation of Phase Change Material Integrated Wavy Finned Single Pass Solar Air Heater", Journal of Energy Storage, Vol. 32, (2020).
  21. Madadi Avargani, V., Zendehboudi, S., Rahimi, A., and Soltani, S., "Comprehensive Energy, Exergy, Enviro-Exergy, and Thermo-Hydraulic Performance Assessment of a Flat Plate Solar Air Heater with Different Obstacles", Applied Thermal Engineering, Vol. 203, P. 117907, (2022).
  22. Layek, A., Saini, J. S., and Solanki, S. C., "Second Law Optimization of a Solar Air Heater Having Chamfered Rib-Groove Roughness on Absorber Plate", Renewable Energy, Vol. 32, No. 12, Pp. 1967-1980, (2007).
  23. Alam, T., Meena, C.S., Balam, N. B., Kumar, A., and Cozzolino, R., "Thermo-Hydraulic Performance Characteristics and Optimization of Protrusion Rib Roughness in Solar Air Heater", Energies, Vol. 14, No. 11, p. 3159, (2021).
  24. Foruzan-nia, M., Gandjalikhan-Nassab, S.A., and Ansari, A.B., "Numerical Simulation of Flow and Thermal Behavior of Radiating Gas Flow in Plane Solar Heaters", Journal of Thermal Science and Engineering Applications, Vol. 12, No. 3, Pp. 1-16, (2019).
  25. Gandjalikhan-Nassab, S.A., and Sheikh-Nejad, Y., "Exploitation of Radiating Gas in Improving Solar Gas Heater Performance", Energy Sources - Part A: Recovery, Utilization, and Environmental Effects, Pp. 1-18, (2021).
  26. Alkilani, M. M., Sopian, K., Mat, S. B., and Alghoul, M. A., "Output Air Temperature Prediction in a Solar Air Heater Integrated with Phase Change Material", European Journal of Scientific Research, Vol. 27, No. 3, Pp. 334-341, (2009).
  27. Krishnananth, S. S., and Murugavel, K. K., "Experimental Study on Double-Pass Solar Air Heater with Thermal Energy Storage", Journal of King Saud University - Engineering Sciences, Vol. 25, No. 2, Pp. 135-140, (2013).
  28. Omojaro, A. P., and Aldabbagh, L. B. Y., "Experimental Performance of Single and Double Pass Solar Air Heater with Fins and Steel Wire Mesh as Absorber", Applied Energy, Vol. 87, No. 12, Pp. 3759-3765, (2010).
  29. Stanley, S.G., and Murugavel, K.K., "Experimental Investigation of Thermal Performance of a Single and Double Pass Solar Air Heater with Arc-Like Structures as the Absorber Plate", Journal of Computational and Theoretical Nanoscience, Vol. 14, No. 7, Pp. 3410-3415, (2017).
  30. Chen, W., and Liu, W., "Numerical Analysis of Heat Transfer in a Composite Wall Solar-Collector System with a Porous Absorber", Applied Energy, Vol. 78, No. 2, Pp. 137-149, (2004).
  31. Gupta, B., Waiker, J. K., Manikpuri, G. P., and Bhalavi, B. S., "Experimental Analysis of Single and Double Pass Smooth Plate Solar Air Collector with and without Porous Media", American Journal of Engineering Research, Vol. 2, No. 12, Pp. 144-149, (2013).
  32. Salih, M. M. M., Alomar, O. R., and Yassien, H. N. S., "Impacts of Adding Porous Media on Performance of Double-Pass Solar Air Heater under Natural and Forced Air Circulation Processes". International Journal of Mechanical Sciences, Vol. 210, P. 106738, (2021).
  33. Collins, M. R., and Abulkhair, H., "An Evaluation of Heat Transfer and Effectiveness for Unglazed Transpired Solar Air Heaters", Solar Energy, Vol. 99, Pp. 231-245, (2014).
  34. Mahboub, C., Moummi, N., Brima, A., and Moummi, A., "Experimental Study of New Solar Air Heater Design", International Journal of Green Energy, Vol. 13, No. 5, Pp. 521-529, (2016).
  35. Bakri, B., Eleuch, O., Ketata, A., Driss, S., Driss, Z., and Benguesmia, H., "Study of the Turbulent Flow in a Newly Solar Air Heater Test Bench with Natural and Forced Convection Modes", Energy, Vol. 161, Pp. 1028-1041, (2018).
  36. Dheyab, H.S., Al-Jethelah, M., Yassen, T., and Khalil, T., "Experimental Study of the Optimum Air Gap of a Rectangular Solar Air Heater", Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, Vol. 59, No. 2, Pp. 318-329, (2019).
  37. Sheikh-Nejad, Y., and Gandjalikhan-Nassab, S. A., "Enhancement of Solar Chimney Performance by Passive Vortex Generator", Renewable Energy, Vol. 169, Pp. 437-450, (2021).
  38. COMSOL Multiphysics Commercial Software User's Guide, Version 5.5, (2019).
  39. Pellew, A., and Southwell, R. V., "On Maintained Convective Motion in a Fluid Heated from Below", Royal Society, Vol. 176, No. 966, Pp. 312-343, (1940).
  40. Bejan, A., "Convection Heat Transfer", John Wiley & Sons, New York, 4th Edition, (2013).

 

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