نوع مقاله : مقالة‌ تحقیقی‌ (پژوهشی‌)

نویسنده

دانشکده مکانیک، دانشکده فنی، دانشگاه خوارزمی، تهران، ایران

چکیده

محفظة احتراق با گردابة به دام افتاده محفظه‌ای فشرده است که کارایی بالایی در پایداری شعله دارد. در این مطالعه، جریان واکنشی مغشوش در محفظة احتراق با گردابة به دام افتاده به صورت عددی شبیه‌سازی شده است. مدل‌های توربولانسی شبیه‌سازی مقیاس انطباقی و K-ω-SST، و رویکردهای احتراقی انتقال اجزاء و تابع چگالی احتمال برای مدل‌سازی توربولانس و احتراق مورد استفاده قرار گرفته‌اند. به منظور اعتبارسنجی مدل عددی، نتایج عددی با نتایج آزمایشگاهی موجود مقایسه شده است. انطباق مناسبی بین مقادیر متوسط و نوسانی دما، مقادیر صدور آلاینده‌ها (مونوکسید کربن، هیدروکربن نسوخته و اکسیدهای نیتروژن) و همچنین راندمان احتراق به‌دست آمده از حل عددی و نتایج آزمایشگاهی وجود دارد. ضمناً، شبیه‌سازی برای مقادیر مختلف نسبت هم ارزی و دمای ورودی جریان اصلی انجام شد و نتایج نشان می‌دهد که در یک مقدار ثابت نسبت هم ارزی، با افزایش دمای جریان اصلی، راندمان احتراق افزایش و شاخص‌های آلایندگی مونوکسیدکربن و هیدروکربن نسوخته کاهش می‌یابند.

کلیدواژه‌ها

عنوان مقاله [English]

Numerical Simulation of Turbulent Reacting flow in a Trapped Vortex Combustor

نویسنده [English]

  • Mostafa Esmaeili

Department of Mechanical Engineering, Faculty of Engineering, Kharazmi University, Tehran, Iran.

چکیده [English]

Trapped vortex combustor (TVC) is a compact combustor which represents the high efficiency in flame stabilization. In this study, turbulent reacting flow through trapped vortex combustor is numerically simulated. In order to model turbulence, the K-ω-SST and scale adaptive simulation (SAS) models, and to model combustion, the species transport and probability density function (PDF) approaches are used. To verify the numerical model, numerical results are compared with the available experimental data. There is a good agreement between the mean and RMS values of temperature and emission indices (CO, unbernt hydrocarbon (UHC) and NOx) obtained from numerical results and experimental data. Moreover, simulation is performed for different values of equivalence ratios and mainstream inlet temperatures and results show that with a constant value of equivalence ratio, by increasing the mainstream inlet temperature, combustion efficiency increases, while CO and UHC emission indices decrease.

کلیدواژه‌ها [English]

  • Trapped vortex combustor
  • Reacting turbulent flow
  • Emission indices
  • Combustion efficiency
[1]     Hsu, K., Goss, L., Trump, D. and Roquemore, W., "Performance of a Trapped-Vortex Combustor," AIAA Paper, Vol. 810, 1995.
[2]     Roquemore, W., Shouse, D., Burrus, D. and et.al., "Vortex Combustor Concept for Gas Turbine Engines," Proceeding 39th Aerospace Sciences Meeting and Exhibit, January 2001.
[3]     Hsu, K.-Y., Goss, L. and Roquemore, W., "Characteristics of a Trapped-Vortex Combustor," Journal of Propulsion and Power, Vol. 14, No. 1, 1998, pp. 57-65.
[4]     Esmaili, M., "
[5]     Katta, V.R. and Roquemore, W., Study on Trapped-Vortex Combustor-Effect of Injection on Flow Dynamics," Journal of Propulsion and Power, Vol. 14, No. 3, 1998, pp. 273-281.
[6]     Agarwal, K.K., Krishna, S. and Ravikrishna, R., "Mixing Enhancement in a Compact Trapped Vortex Combustor," Combustion Science and Technology, Vol. 185, No. 3, 2013, pp. 363-378.
[7]     Burguburu, J., Cabot, G., Renou, B., Boukhalfa, A., Cazalens, M.M., "Flame Stabilization by Hot Products Gases Recirculation in a Trapped Vortex Combustor," Proceeding of American Society of Mechanical Engineers, June 2012, pp. 319-328.
[8]     Jin, Y., Li, Y., He, X., Zhang, J., Jiang, B., Wu, Z. Song, Y., Experimental Investigations on Flow Field and Combustion Characteristics of a Model Trapped Vortex Combustor, Applied Energy, Vol. 134, 2014, pp. 257-269.
[9]     Kumar, P.E. and Mishra, D., Combustion Noise Characteristics of an Experimental 2D Trapped Vortex Combustor, Aerospace Science and Technology, Vol. 43, 2015, pp. 388-394.
[10]  Wu, Z., Jin, Y., He, X., Xue, C. and Hong, L., "Experimental and Numerical Studies on a Trapped Vortex Combustor with Different Struts Width, Applied Thermal Engineering, Vol. 91, 2015, pp. 91-104.
[11]  Kumar, P.E. and Mishra, D., "Combustion Characteristics of a 2D Twin Cavity Trapped Vortex Combustor," Journal of Engineering for Gas Turbines and Power, 2017.
[12]  Zbeeb, K., "Syngas Heating Value Effects on Performance and Emissions of a Trapped Vortex Combustor," Journal of Energy Resources Technology, Vol. 138, No. 5, 2016, pp. 052209.
[13]  Chen, S., Chue, R.S., Yu, S.C.,  Schlüter, J. U., "Spinning Effects on a Trapped Vortex Combustor," Journal of Propulsion and Power, 2016, pp. 1133-1145.
[14]  Ghenai, C., Zbeeb, K. and Janajreh, I., "Combustion of Alternative Fuels in Vortex Trapped Combustor," Energy Conversion and Management, Vol. 65, 2013, pp. 819-828.
[15]  Bruno, C. and Losurdo, M., 'The Trapped Vortex Combustor: an Advanced Combustion Technology for Aerospace and Gas Turbine Applications,'  in: Advanced Combustion and Aerothermal Technologies, Eds., Springer, pp. 365-384, 2007.
[16]  Kumar, P.E. and Mishra, D., "Numerical Investigation of the Flow and Flame Structure in an Axisymmetric Trapped Vortex Combustor, Fuel, Vol. 102, pp. 78-84, 2012.
[17]  Kumar, P.E. and Mishra, D., "Numerical Simulation of Cavity Flow Structure in an Axisymmetric Trapped Vortex Combustor, Aerospace Science and Technology, Vol. 21, No. 1, 2012, pp. 16-23.
[18]  Merlin, C., Domingo, P., Vervisch, L., "Large Eddy Simulation of Turbulent Flames in a Trapped Vortex Combustor (TVC)–A Flamelet Presumed-pdf Closure Preserving Laminar Flame Speed," Comptes Rendus Mécanique, Vol. 340, Issue 11-12, 2012, pp. 917-932.
[19]  Jiang, B., He, X., Jin, Y. and et. al., "Effects of Multi-Orifice Configurations of the Quench Plate on Mixing Characteristics of the Quench Zone in an RQL-TVC Model," Experimental Thermal and Fluid Science, Vol. 8, 2016, pp. 57-68.
[20]  Deng, Y. and Su, F., "Low Emissions Trapped Vortex Combustor," Aircraft Engineering and Aerospace Technology, An International Journal, Vol. 88, No. 1, 2016, pp. 33-41.
[21]  Fluent, User’s Guide, 2014.
[22]  Menter, F. R., Kuntz, M. and Langtry, R., Ten Years of Experience with the SST Turbulence Model Turbulence, Heat and Mass Transfer 4, Begell House Inc, 2003, pp. 625-632.
[23]  Menter, F. R., "Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications," AIAA Journal, Vol. 32, No. 8, 1994, pp. 1598-1605.
[24]  Menter, F.R. "Review of the Shear-Stress Transport Turbulence Model Experience from an Industrial Perspective, International Journal of Computational Fluid Dynamics, Vol. 23, No. 4, 2009, pp. 305-316.
[25]  Rotta, J. C., Turbulente Strömungen: Eine Einführung in Die Theorie und ihre Anwendung, Springer-Verlag, 2013.
[26]  Egorov, Y., Menter, F., Lechner, R. and Cokljat, D. "The Scale-Adaptive Simulation Method for Unsteady Turbulent Flow Predictions. Part 2: Application to Complex Flows, Flow," Turbulence andCombustion, Vol. 85, No. 1, 2010, pp. 139-165.
[27]  Menter, F. and Egorov, Y., "The Scale-Adaptive Simulation Method for Unsteady Turbulent Flow Predictions. Part 1: Theory and Model Description, Flow," Turbulence and Combustion, Vol. 85, No. 1, 2010, pp. 113-138.