شبیه‌سازی عددی انتقال گرمای جریان آشفته نانو سیال غیرنیوتنی در مبدل گرمایی دولوله‌ای مارپیچ

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشیار و عضو هیئت علمی گروه مکانیک- دانشکده فنی- دانشگاه گیلان

2 دانشکده فنی مکانیک ، دانشگاه گیلان، رشت، ایران

3 دانشکده فنی مکانیک، دانشگاه گیلان، رشت ایران

چکیده

در این پژوهش رفتار گرمایی و هیدرودینامیکی جریان آشفته نانوسیال غیرنیوتنی در آرایش جریان مخالفدر یک مبدلگرمایی دولولهای مارپیچ به صورت عددی شبیه‌سازی شده است. از محلول پودرکربوکسی متیل سلولز در آب با درصد جرمی 1/0% همراه با نانوذره آلومینیوم‌اکسید به عنوان سیال عامل استفاده شده است. از نرم افزار دینامیک سیالات محاسباتی فلوئنت جهت حل معادلات استفاده شده که نتایج این حل عددی با داده‌های تجربی پیشین مطابقت خیلی خوبی داشته است. نقش و تأثیر پارامترهای مهم مانند انحنای مارپیچ، عدد رینولدز و درصد حجمی نانوذرات آلومینیوماکسید روی انتقال گرما مورد بررسی قرار گرفته است. نتایج نشان می‌دهد با افزایش نسبت انحنا در اعداد دین ثابت، عدد ناسلت و ضریب اصطکاک افزایش می‌یابد. نیروی گریز از مرکز ناشی از انحنای لوله‌های مارپیچ سبب ایجاد جریان ثانویه در مبدل شده به طوری که میزان انتقال گرما و افت فشار به ترتیب تا 35% و 30% نسبت به لوله‌های مستقیم افزایش پیدا کرده است. نتایج نشان می‌دهد که اضافه کردن نانوذرات آلومینیوم‌اکسید به سیال پایه برای جریان با عدد رینولدز و عدد دین ثابت، باعث افزایش انتقال گرما و افزایش افت فشار جریان در لوله‌های مارپیچ می‌شود. اثر روش‌های افزایش انتقال گرما بر شاخص هیدرودینامیکی نیز بررسی شد به طوری که در کویل‌های مارپیچ با کاهش نسبت انحنا و افزایش غلظت حجمی نانوذرات مقدار شاخص هیدرودینامیکی نیز بیشتر شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical Simulation of Heat Transfer Turbulent Flow for Non-Newtonian Nanofluid in a Double Pipe Helical Heat Exchanger

نویسندگان [English]

  • Kourosh Javaherdeh 1
  • Seyed Shahab Mozafarie 2
  • zeinab Zare Talab 3
1 Instructor of Department of Mechanical Engineering, Faculty of Engineering, University of Guilan
2 Faculty of Mechanical Engineering, University of Guilan, Rash, Iran
3 Faculty of Mechanical Engineering, University of Guilan, Rasht, Iran
چکیده [English]

In this research, the thermal and hydrodynamic behavior of a non-Newtonian nanofluid turbulent flow in the counterflow arrangement in a double pipe helical heat exchanger is numerically simulated. A solution of carboxymethyl cellulose powder in water with a mass percentage of 0.1% with a nanoparticle of aluminum oxide as a working fluid has been used. The computational fluid dynamics commercial software Fluent was used to solve the governing equations, the results were in a good agreement with experimental data. The effect of important parameters such as curvature, Reynolds number and volume percentage of aluminum oxide nanoparticles on the heat transfer has been investigated. The results show that as the curvature ratio increases in constant Dean (Dn) numbers, the Nu number and the coefficient of friction increase. The addition of nanoparticles of aluminum oxide to the base fluid for the flow with the constant Reynolds and Dn number increases the heat transfer and increases the pressure drop in the helically coiled tubes. The centrifugal force generated by the curvature of the coiled tubes results in a secondary flow in the heat exchanger so that the heat transfer and pressure drop increased up to 35% and 30%, respectively, compared to the straight tubes. The effect of heat transfer enhancement methods on the hydrodynamic index has also been studied, so that in the helical coils, the amount of hydrodynamic index increased with decreasing curvature ratio and increasing the volume concentration of nanoparticles.

کلیدواژه‌ها [English]

  • Double pipe helical heat exchanger
  • Numerical simulation
  • Heat transfer
  • Nanofluid
  • Turbulent flow
[1] J.C. Maxwell, Treatise on Electricity and Magnetism, Clarendon Press, Oxford, U.K, 1881.
[2] S.U.S. Choi, J. Eastman, Enhancing thermal conductivity of fluids with nanoparticles, 1995.
[3] Z. Wu, L. Wang, B. Sunden, Pressure drop and convective heat transfer of water and nanofluids in a double-pipe helical heat exchanger, Applied Thermal Engineering, 60 (2013) 266-274.
[4] S. Vashisth, V. Kumar, K. Nigam, A Review on the Potential Applications of Curved Geometries in Process Industry, Industrial & Engineering Chemistry Research 47 (2008) 3291-3337.
[5] M.H. Kayhani, M. Nazari, H. Soltanzadeh, M. Heyhat, F. Kowsary, Experimental analysis of turbulent convective heat transfer and pressure drop of AI2o3/water nanofluid in horizontal tube, Micro & Nano Letters, IET, 7 (2012) 223-227.
[6] P. Naphon, S. Wongwises, A review of flow and heat transfer characteristics in curved tubes, Renewable and Sustainable Energy Reviews, 10 (2006) 463-490.
[7] F. Sarrafzadeh Javadi, S. Sadeghipour, S. Rahman, G. BoroumandJazi, B. Rahmati, M.M. Elias, M.R. Sohel, The effects of nanofluid on thermophysical properties and heat transfer characteristics of a plate heat exchanger, International Communications in Heat and Mass Transfer, 44 (2013) 58-63.
[8] A. Akbarinia, A. Behzadmehr, Numerical study of laminar mixed convection of a nanofluid in horizontal curved tubes, Applied Thermal Engineering, 27 (2007) 1327–1337.
[9] A. Akbarinia, R. Laur, Investigating the diameter of solid particles effect on a laminar nanofluid flow in a curved tube using two phase approach, International Journal of Heat and Fluid Flow, 30 (2009) 706-714.
[10] J. Choi, Y. Zhang, Numerical simulation of laminar forced convection heat transfer of Al2O3–water nanofluid in a pipe with return bend, International Journal of Thermal Sciences 55 (2012) 90–102.
[11] G. Huminic, A. Huminic, Heat transfer characteristics in double tube helical heat exchangers using nanofluids, International Journal of Heat and Mass Transfer, 54 (2011) 4280-4287.
[12] M. Kahani, S. Zeinali Heris, S. M. Mousavi, Effects of Curvature Ratio and Coil Pitch Spacing on Heat Transfer Performance of Al 2 O 3 /Water Nanofluid Laminar Flow through Helical Coils, Journal of Dispersion Science and Technology, 34 (2013) 1704-1712.
[13] S. Pawar, V. Sunnapwar, Experimental studies on heat transfer to Newtonian and non-Newtonian fluids in helical coils with laminar and turbulent flow, Experimental Thermal and Fluid Science, 44 (2013) 792–804.
[14] S. Pawar, V. Sunnapwar, Experimental and CFD investigation of convective heat transfer in helically coiled tube heat exchanger, Chemical Engineering Research and Design, 92 (2014) 2294-2312.
[15] D. Majidi, H. Alighardashi, F. Farhadi, Experimental studies of heat transfer of air in a double-pipe helical heat exchanger, Applied Thermal Engineering, 133 (2018) 276-282.
[16] W. Tseng, F. Tzeng, Effect of Ammonium Polyacrylate on Dispersion and Rheology of Aqueous ITO Nanoparticle Colloids, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 276 (2006) 34-39.
[17] H. Xie, L. Chen, Q. Wu, Measurements of the viscosity of suspensions (nanofluids) containing nanosized Al2O3 particles, High Temperatures - High Pressures, 37 (2008) 127-135.
[18] T.H. Shih, W. Liou, A. Shabbir, Z. Yang, J. Zhu, A New k-(Eddy Viscosity Model for High Reynolds Number Turbulent Flows - Model Development and Validation, Comput. Fluids, 24 (1994) 227-238.
[19] V. Ranade, Computational Flow Modelling For Chemical Reactor Engineering, in, Academic Press, London, 2002.
[20] J. Js, S. Mahajani, J. Mandal, K. Iyer, P.K. Vijayan, CFD analysis of single-phase flows inside helically coiled tubes, Computers & Chemical Engineering, 34 (2010) 430-446.
[21] M. Bizhani, E. Kuru, Modeling Turbulent Flow of Non-Newtonian Fluids Using Generalized Newtonian Models, ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering,  (2015) 623-632.
[22] W. Aly, Numerical study on turbulent heat transfer and pressure drop of nanofluid in coiled tube-in-tube heat exchangers, Energy Conversion and Management, 79 (2014) 304-316.
[23] M. Wolfshtein, The Velocity and Temperature Distribution of One-Dimensional Flow with Turbulence Augmentation and Pressure Gradient, International Journal of Heat and Mass Transfer, 12 (1969) 301-318.
[24] W.P. Jones, B. Launder, The prediction of laminarization with a two-equation model of turbulence, International Journal of Heat and Mass Transfer, 15 (1972) 301-314.
[25] ANSYS FLUENT 12.0 UDF Manual, in, 2011, pp. 14-16.
[26] S. V. Patankar, Numerical Heat Transfer and Fluid Flow, in, Hemisphere, Washington, DC, 1980, pp. 60–74.
[27] J. Js, S. Mahajani, J. Mandal, P. K. Vijayan, R. Bhoi, Experimental CFD estimation of heat transfer in helically coiled heat exchanger, Chemical Engineering Research & Design, 86 (2008) 221-232.
[28] P. Mlynarczyk, P. Cyklis, The Influence of the Spatial Discretization Methods on the Nozzle Impulse Flow Simulation Results, Procedia Engineering, 157 (2016) 396-403.
[29] M. Heyhat, F. Kowsary, A. Rashidi, M.H. Momenpour, A. Amrollahi, Experimental investigation of laminar convective heat transfer and pressure drop of water-based Al2O3 nanofluids in fully developed flow regime, Experimental Thermal and Fluid Science, 44 (2013) 483–489.
[30] Y. Xuan, W. Roetzel, Conception for Heat Transfer Correlation of Nanofluids, International Journal of Heat and Mass Transfer 43 (2000) 3701-3707.
[31] B. Choon Pak, Y. Cho, Hydrodynamic and Heat Transfer Study of Dispersed Fluids With Submicron Metallic Oxide Particle, Experimental Heat Transfer 11 (1998) 151-170.
[32] E. F. Schmidt, Wärmeübergang und Druckverlust in Rohrschlangen, Chemie Ingenieur Technik 39 (1967) 781-789.
[33] V. Gnielinski, Heat Transfer Coefficients for Turbulent Flow in Concentric Annular Ducts, Heat Transfer Engineering, 30 (2009) 431-436.
[34] V. Gnielinski, New equation for heat and mass transfer in turbulent pipe and channel flow, Int Chem Eng 16 (1976) 359-363.
[35] V. Gnielinski, Heat transfer and pressure drop in helically coiled tubes, Heat Transfer, Proceedings of the International Heat Transfer Conference, 6 (1986) 2847-2854.
[36] J.-F. Fan, W.K. Ding, J.-F. Zhang, Y. L. He, W.-Q. Tao, A performance evaluation plot of enhanced heat transfer techniques oriented for energy-saving, International Journal of Heat and Mass Transfer 52 (2009) 33-44.