بهبود مشخصه‌های احتراقی مخلوط هیدروژن – هوا با استفاده از ساختار ماژولار در محفظه های احتراقی در مقیاس میکرو

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار، دانشکده مهندسی مکانیک، دانشگاه شیراز

2 استاد، دانشگده مهندسی مکانیک، دانشگاه صنعتی شریف

چکیده

د
در کار حاضر، تاثیر استفاده از ساختار ترکیبی بر مشخصه‌های احتراقی مخلوط هیدروژن-هوا، با استفاده از شبیه‌سازی عددی سه­ بعدی و درنظر گرفتن سینتیک شیمیایی جزئی و ضرایب نفوذ مولکولی، بررسی می ­شود. تاثیر پارامترهای سرعت جریان ورودی، رسانش حرارتی دیوار و انحنای دیوار بر روی مشخصه­های احتراق هیدروژن-هوا برای دو ساختار ساده و ترکیبی بررسی شد. نتایج نشان می­دهد که استفاده از ساختار ترکیبی تاثیر بسزایی بر روی  مشخصه­ های احتراقی و مکان شعله می­گذارد. در ساختار ترکیبی، نقش انتقال حرارت، به­واسطه سیال ثانویه، در مقایسه با ساختار ساده افزایش می­یابد که منجربه بهبود مشخصه­های حرارتی محفظه احتراق و کاهش نقش رسانش حرارتی دیوار در ساختار ترکیبی می­ شود. استفاده از آرایش ترکیبی در مقایسه با ساختار ساده باعث می­شود که در سرعت ورودی یکسان، شعله به­صورت مشخصی در فاصله نزدیک­تر از ورودی محفظه احتراق تشکیل شود. تاثیر نسبت انحنای لوله به شعاع لوله با درنظرگرفتن دو مقدار 1 و 2 بررسی و مشاهده شد که در نسبت انحنای کمتر، به­علت نقش پیش ­گرم­ کردن جریان ورودی توسط محصولات، مکان جبهه شعله به ورودی نزدیک­تر و توزیع دما درون محفظه احتراق بهتر خواهد بود.

کلیدواژه‌ها


عنوان مقاله [English]

Improvement of combustion characteristics for hydrogen-air mixture using modular structure in a novel micro combustor

نویسندگان [English]

  • Alireza Alipoor 1
  • Mohammad Hassan Saidi 2
1 Mechanical Engineering School, Shiraz University
2 Sharif University of Technology
چکیده [English]

In the present work, the effect of using modular structure on combustion characteristics of the premixed lean hydrogen-air mixture is investigated by utilizing the three-dimensional CFD model, detailed chemistry and transport taking into account heat transfer through the wall combustor. Combustion characteristics are studied for different parameters, namely inlet velocity, wall thermal conductivity and tube curvature for modular structure and it compares with results of simple structure. The results show that using modular structure can significantly move flame front toward inlet section. In modular structure, the role of heat transfer due to secondary fluid increases in comparison with heat transfer in combustor walls. It improves thermal stability in the micro combustor and therefore, the role of wall thermal conductivity and heat transfer in wall combustor will be decreased for modular structure. Using modular structure for lower tube curvature is more effective which it has been shown for tube curvature of one and two.

کلیدواژه‌ها [English]

  • Combustion in Micro Scale
  • Modular structure
  • U-shaped micro combustor
  • numerical simulation
  1. G. Pizza, J. Mantzaras and C. E. Frouzakis, “Flame dynamics in catalytic and non-catalytic mesoscale microreactors,” Catalysis Today, 155, NO. 1–2, 2010, pp. 123–130.
  2. J. Zhou, Y. Wang, W. Yang, J. Liu, Z. Wang and K. Cen, “Combustion of hydrogen–air in catalytic micro-combustors made of different material,” International Journal of Hydrogen Energy, 34, NO. 8, 2009, pp. 3535–3545.
  3. F. Lucci, C. E. Frouzakis and J. Mantzaras, “Three-dimensional direct numerical simulation of turbulent channel flow catalytic combustion of hydrogen over platinum,” Proceedings of the Combustion Institute, 34, NO. 2, 2013, pp. 2295–2302.
  4. Y. Yan et al., “Numerical simulation of the effect of hydrogen addition fraction on catalytic micro-combustion characteristics of methane-air,” International Journal of Hydrogen Energy, 39, NO. 4, 2014, pp. 1864–1873.
  5. A. Brambilla, C. E. Frouzakis, J. Mantzaras, A. Tomboulides, S. Kerkemeier and K. Boulouchos, “Detailed transient numerical simulation of H2/air hetero-/homogeneous combustion in platinum-coated channels with conjugate heat transfer,” Combustion and Flame, 161, NO. 10, 2014, pp. 2692–2707.
  6. E. Jiaqiang, W. Zuo, X. Liu, Q. Peng, Y. Deng and H. Zhu, “Effects of inlet pressure on wall temperature and exergy efficiency of the micro-cylindrical combustor with a step,” Applied Energy, 175, 2016, pp. 337–345.
  7. M. Chen and J. Buckmaster, “Modelling of combustion and heat transfer in ‘Swiss roll’ micro-scale combustors,” Combustion Theory and Modelling, 8, NO. 4, 2004, pp. 701–720.
  8. N. I. Kim et al., “Flame stabilization and emission of small Swiss-roll combustors as heaters,” Combustion and Flame, 141, NO. 3, 2005, pp. 229–240.
  9. N. I. Kim et al., “Development and scale effects of small Swiss-roll combustors,” Proceedings of the Combustion Institute, 31, NO. 2, 2007, pp. 3243–3250.
  10. J. Wan, A. Fan, H. Yao and W. Liu, “Effect of pressure on the blow-off limits of premixed CH4/air flames in a mesoscale cavity-combustor,” Energy, 91, 2015, pp. 102–109.
  11. W. Zuo, E. Jiaqiang, H. Liu, Q. Peng, X. Zhao and Z. Zhang, “Numerical investigations on an improved micro-cylindrical combustor with rectangular rib for enhancing heat transfer,” Applied Energy, 184, 2016, pp. 77–87.
  12. J. Wan, A. Fan, K. Maruta, H. Yao and W. Liu, “Experimental and numerical investigation on combustion characteristics of premixed hydrogen/air flame in a micro-combustor with a bluff body,” International Journal of Hydrogen Energy, 37, NO. 24, 2012, pp. 19190–19197.
  13. Y. Yan et al., “Numerical study on catalytic combustion and extinction characteristics of pre-mixed methane–air in micro flatbed channel under different parameters of operation and wall,” Fuel, 180, 2016, pp. 659–667.
  14. A. Fan, J. Wan, K. Maruta, H. Yao and W. Liu, “Interactions between heat transfer, flow field and flame stabilization in a micro-combustor with a bluff body,” International Journal of Heat and Mass Transfer, 66, 2013, pp. 72–79.
  15. L. Zhang, J. Zhu, Y. Yan, H. Guo and Z. Yang, “Numerical investigation on the combustion characteristics of methane / air in a micro-combustor with a hollow hemispherical bluff body,” Energy Conversion and Management, 94, 2015, pp. 293–299.
  16. A. Fan, J. Wan, Y. Liu, B. Pi, H. Yao and W. Liu, “Effect of bluff body shape on the blow-off limit of hydrogen/air flame in a planar micro-combustor,” Applied Thermal Engineering, 62, NO. 1, 2014, pp. 13–19.
  17. G. Bagheri, S. E. Hosseini and M. A. Wahid, “Effects of bluff body shape on the flame stability in premixed micro-combustion of hydrogen–air mixture,” Applied Thermal Engineering, 67, NO. 1–2, 2014, pp. 266–272.
  18. M. Hossein, S. Moghaddam, K. Mazaheri and A. Alipoor, “Numerical study of bluff body effect in lean premix hydrogen/air combustion in a micro- scale combustor,” Modares Mechanical Engineering, 14, NO. 13, 2015, pp. 86–94.
  19. S. K. Chou, W. M. Yang, J. Li and Z. W. Li, “Porous media combustion for micro thermophotovoltaic system applications,” Applied Energy, 87, NO. 9, 2010, pp. 2862–2867.
  20. J. F. Pan, D. Wu, Y. X. Liu, H. F. Zhang, A. K. Tang and H. Xue, “Hydrogen / oxygen premixed combustion characteristics in micro porous media combustor,” Applied Energy, 160, 2015, pp. 802–807.
  21. J. Li, Y. Wang, J. Shi and X. Liu, “Dynamic behaviors of premixed hydrogen – air flames in a planar micro-combustor filled with porous medium,” Fuel, 145, 2015, pp. 70–78.
  22. K. Maruta, J. K. Parc, K. C. Oh, T. Fujimori, S. S. Minaev and R. V. Fursenko, “Characteristics of Microscale Combustion in a Narrow Heated Channel,” Combustion, Explosion, and Shock Waves, 40, NO. 5, 2004, pp. 516–523.
  23. F. Richecoeur and D. C. Kyritsis, “Experimental study of flame stabilization in low Reynolds and Dean number flows in curved mesoscale ducts,” Proceedings of the Combustion Institute, 30, NO. 2, 2005, pp. 2419–2427.
  24. M. Baigmohammadi, S. Tabejamaat and J. Zarvandi, “Numerical study of the behavior of methane-hydrogen/air pre-mixed flame in a micro reactor equipped with catalytic segmented bluff body,” Energy, 85, 2015, pp. 117–144.
  25. J. Zarvandi, S. Tabejamaat and M. Baigmohammadi, “Numerical study of the effects of heat transfer methods on CH4/(CH4 + H2)-AIR pre-mixed flames in a micro-stepped tube,” Energy, 44, NO. 1, 2012, pp. 396–409.
  26. M. Baigmohammadi, S. Sarrafan Sadeghi, S. Tabejamaat and J. Zarvandi, “Numerical study of the effects of wire insertion on CH4(methane)/AIR pre-mixed flame in a micro combustor,” Energy, 54, 2013, pp. 271–284.
  27. A. Alipoor and M. H. Saidi, “Numerical study of hydrogen-air combustion characteristics in a novel micro-thermophotovoltaic power generator,” Applied Energy, 199, 2017, pp. 382–399.
  28. R. A. Yetter, F. L. Dryer and H. Rabitz, “A Comprehensive Reaction Mechanism For Carbon Monoxide/Hydrogen/Oxygen Kinetics,” Combustion Science and Technology, 79, 1991, pp. 97–128.
  29.  “Transport: A Software package for the evaluation of gas-phase, multi component transport properties,” CHEMKIN Collection Release 3.6 (TRA-036-1), 2000.
  30. A. Alipoor and K. Mazaheri, “Combustion characteristics and flame bifurcation in repetitive extinction-ignition dynamics for premixed hydrogen-air combustion in a heated micro channel,” Energy, 109, 2016, pp. 650–663.
  31. A. Alipoor, K. Mazaheri and A. Shamooni, “Asymmetric hydrogen flame in a heated micro-channel : Role of Darrieus e Landau and thermal-diffusive instabilities,” International Journal of Hydrogen Energy, 41, NO. 44, 2016, pp. 20407–20417.
  32. A. Alipoor, K. Mazaheri, A. Shamooni Pour, Y. Mahmoudi and A. Shamooni, “Asymmetric hydrogen flame in a heated micro-channel : Role of Darrieus e Landau and thermal-diffusive instabilities,” International Journal of Hydrogen Energy, 41, NO. 44, 2016, pp. 1–11.