مدل سازی عددی اثر انتقال نانو ذرات در جریان جابه‌جایی ترکیبی نانوسیال با خواص متغیر در محفظه مربعی با درگاه ورود و خروج جریان

نویسندگان

دانشگاه کاشان

چکیده

میدان جریان، انتقال حرارت و انتقال ذرات در جابه‌جایی ترکیبی نانوسیال آب- اکسید آلومینیوم با فرض مخلوط غیر همگن در محفظه مربعی با درگاه ورود و خروج جریان به‌صورت عددی مدل‌سازی شده است. برای حل معادلات حاکم به صورت بی‌بعد، از روش حجم محدود استفاده شده و ارتباط میدان سرعت و فشار با الگوریتم سیمپلر برقرار شده است. مکانیزم‌های انتقال نانوذرات شامل ترموفرسیس، نفوذ براونی و اثر دوفور که سبب عدم یکنواختی غلظت نانوذرات می‌شوند، به عنوان مدل انتقال نانوذرات در نظر گرفته شده و مسئله برای کسرحجمی نانوذرات در محدوده 0 ≤ φb ≤ 0.04، عدد ریچاردسون در محدوده 0.01 ≤ Rif,0 ≤ 1 و دو عدد گراشف Grf,0=104 , 105 بررسی شده است. بر اساس نتایج به‌دست آمده مشاهده شده است که، در جابه‌جایی ترکیبی افزایش کسر حجمی و همچنین افزایش عدد گراشف در تمام محدوده اعداد ریچاردسون، منجر به افزایش انتقال حرارت می‌شود و مدل انتقال با تاثیر گذاری بر غلظت نانوذرات در محفظه سبب تاثیر بر میزان سرعت جریان و انتقال حرارت می‌شود، به‌گونه‌ای که در اختلاف دمای پایین مدل همگن و در اختلاف دمای بالا مدل انتقال، عدد ناسلت متوسط بیشتری پیش‌بینی می‌کند.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical modeling of nanoparticles transport effect in mixed convection of nanoï‌‚uid with variable properties in a square cavity with inlet and outlet port

نویسندگان [English]

  • G. A. Sheikhzadeh
  • S.P. Ghaffari
چکیده [English]

In this paper, the flow field, heat transfer and nanoparticles transport in Al2O3-water nanofluid mixed convection in a square enclosure with inlet and outlet port has been studied numerically. The dimensionless transport equations are solved numerically with a finite volume approach using the SIMPLER algorithm. Nanoparticles transport mechanisms such as Brownian diffusion, thermophoresis and Dufour effect that cause non-uniform concentration distribution are intended in nanoparticles transport model. The study has been carried out for the nanoparticles volume fraction in the range 0 ≤ φb ≤ 0.04, Richardson numbers 0.01 ≤ Rif,0 ≤ 1with two Grashof number Grf,0=104 , 105. The results show that in mixed convection by increasing volume fraction of nanoparticles and the Grashof number for each Richardson number, the average Nusselt number increases and the transport model by affecting on nanoparticles concentration influence the amount of flow velocity and heat transfer so that in low temperature difference homogenous model and at high temperature difference the transport model predicts higher average Nusselt number.

کلیدواژه‌ها [English]

  • numerical study
  • Transport model
  • Thermophoresis
  • Brownian diffusion
  • Mixed convection
 
[1] Lee, S., Choi, S.U.S., Li, S., Eastman, J.A., (1999). "Measuring thermal conductivity of fluids containing oxidenanoparticles". ASME Transactions Journal of Heat Transfer, Vol. 121, pp. 280–289.
[2] Eastman, J.A., Choi, S.U.S., Li,W. Yu, S., Thompson, L.J., (2001). "Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles". Journal of Applied Physics Letters, Vol. 78, pp. 718–720.
[3] Xuan, Y., Li, Q., (2000). "Heat transfer enhancement of nanofluids". International Journal of Heat and Fluid Flow, Vol. 21, pp. 58–64.
[4] Tiwari, R.K., Das, M.K., (2007). "Heat transfer augmentation in a two-sided lid-driven differentially heated square cavity utilizing nanofluids". International Journal of Heat and Mass Transfer, Vol. 50, pp. 2002-2018
[5] Muthtamilselvan, M., Kandaswamy1, P., Lee, J., (2010). "Heat transfer enhancement of copper–water nanofluids in a lid-driven enclosure". Communication in Nonlinear Science and Numerical Simulation, Vol. 15, pp. 1501-1510.
[6] Abu-Nada, E., Chamkha, A. J., (2010). "Mixed convection flow in a lid-driven inclined square enclosure filled with a nanofluid". European Journal of Mechanics B/Fluids, Vol. 29, pp. 472-482.
[7] Talebi, F., Mahmoudi, A. H., Shahi, M., (2010). "Numerical study of mixed convection flows in a square lid-driven cavity utilizing nanofluid". International Communication in Heat and Mass Transfer, Vol. 37, pp. 79-90.
[8] Arefmanesh, A., Mahmoodi, M., (2011). "Effects of uncertainties of viscosity models for Al2O3-water nanofluid on mixed convection numerical simulations". International Journal of Thermal Science, Vol. 50, pp. 1706-1719.
[9] Chamkha, A. J., Abu-nada, E., (2012). "Mixed convection flow in single- and double-lid driven square cavities filled with water-Al2O3 nanofluid: Effect of viscosity models". European Journal of Mechanics B/Fluids, Vol. 36, pp. 82-96.
[10] Sheikhzadeh, G.A., Ebrahim Qomi, M., Hajialigol, N., Fattahi, A., (2012). "Numerical study of mixed convection flows in a lid-driven enclosure filled with nanofluid using variable properties". Results in Physics, Vol. 2, pp. 5-13.
[11] Shahi, M., Mahmoudi, A. H., Talebi, F., (2010). "Numerical study of mixed convective cooling in a square cavity ventilated and partially heated from the below utilizing nanofluid". International Communications in Heat and Mass Transfer, Vol. 37, pp. 201-213.
[12] Mahmoudi, A. H., Shahi, M., Talebi, F., (2010). "Effect of inlet and outlet location on the mixed convective cooling inside the ventilated cavity subjected to an external nanofluid". International Communications in Heat and Mass Transfer, Vol. 37, pp. 1158-1173.
[13] Sourtiji, E., Hosseinizadeh, S. F., Gorji-Bandpy, M., Ganji, D. D., (2011). "Effect of water-based Al2O3 nanofluids on heat transfer and pressure drop in periodic mixed convection inside a square ventilated cavity". International Communications in Heat and Mass Transfer, Vol. 38, pp. 1125-1134.
[14] AboueiMehrizi, A., Farhadi, M., Hassanzade Afroozi, H., Sedighi, K., Rabienataj Darz, A. A., (2012). "Mixed convection heat transfer in a ventilated cavity with hot obstacle: Effect of nanofluid and outlet port location". International Communications in Heat and Mass Transfer, Vol. 39, pp. 1000-1008.
[15] Rahman, M. M., Parvin, S., Rahim, N. A., Islam, M. R., Saidur, R., Hasanuzzaman, M., (2012). "Effects of Reynolds and Prandtl number on mixed convection in a ventilated cavity with a heat-generating solid circular block". Applied Mathematical Modelling, Vol. 36, pp. 2056-2066.
[16] Probstein, R.F., (2003). Physicochemical hydrodynamics. Second edition, Wiley Interscience, Hoboken, New Jersey.
[17] Tyndall, J., (1870). "On dust and disease". Proc. R. Inst., Vol. 6, pp. 1-14.
[18] Bird, R. B., Stewart, W. E., (1960). Lightfoot, E. N., second ed, Transport Phenomena, Wiley, New York.
[19] Koo, J., Kleinstreur, C., (2005). "Impact analysis of nanoparticle motion mechanisms on the thermal conductivity of nanofluids". International Communication in Heat and Mass Transfer, Vol. 32, pp. 1111-1118.
[20] Buongiorno, J., (2006). "Convective transports in nanofluids". ASME Transactions Journal of Heat Transfer, Vol. 128, pp. 240-250.
[21] Kuznetsov, A. V., Nield, D. A., (2010). "Natural convection boundary-layer of a nanofluid past a vertical plate". International Journal of Thermal Science, Vol. 49, pp. 243-247.
[22] Mokmeli, A., Saffar-Avval, M., (2010). "Prediction of nanofluid convective heat transfer using the dispersion model". International Journal of Thermal Science, Vol. 49, pp. 471-478.
[23] Pakravan, H. A., Yaghoubi, M., (2011). "Combined thermophoresis, Brownian motion and Dufour effects on natural convection of nanofluids". International Journal of Thermal Science, Vol. 50, pp. 394-402.
[24] Aminfar, H., Haghgoo, M. R., (2012). "Brownian motion and thermophoresis effects on natural convection of alumina-water nanofluid". Journal of Mechanical Engineering Science, Vol. 6, pp. 1-11.
[25] Haddad, Z., Abu-Nada, E., Oztop, H. F., Mataoui, A., (2012). "Natural convection in nanofluids: Are the thermophoresis and Brownian motion effects significant in nanofluid heat transfer enhancement?". International Journal of Thermal Science, Vol. 57, pp. 1-11.
[26] Sheikhzadeh, G. A., Dastmalchi, M., Khorasanizadeh, H., (2012). "Effects of nanoparticles transport mechanisms on Al2O3-water nanofluid natural convection in a square enclosure". International Journal of Thermal Science, Vol.66, pp. 51-62.
[27] Khanafer, K., Vafai, K., (2011). "A critical synthesis of thermophysical characteristics of nanofluids". International Journal of Heat and Mass Transfer, Vol. 54, pp. 4410-4428.
[28] Ho, C. J., Liu, W. K., Chang, Y. S., Lin, C. C., (2010). "Natural convection heat transfer of alumina–water nanofluid in vertical square enclosures, an experimental study". International Journal of Thermal Sciences, Vol. 49, pp. 1345-1353.
[29] Einstein A., (1906). "Eine neue bestimmung der molekul-dimension (A new determination of the molecular dimensions)". Annals of Physics, Vol. 19, pp. 289-306.
[30] Brinkman, H.C., (1952). "The viscosity of concentrated suspensions and solutions". Journal of Chemical Physics, Vol. 20, pp. 571.
[31] Maxwell J.C., (1954). A treatise on electricity and magnetism. Third ed, Dover, New York.
[32] Hamilton, R. L., Crosser, O. K., (1962). "Thermal conductivity of heterogeneous two component system". Industrial and Engineering Chemistry Fundamentals, Vol. 1, pp. 187-191.
[33] Incropera, F. P., DeWitt, D. P., (1996). Introduction to Heat Transfer, third ed. John Wiley & Sons, Inc, New York.
[34] Aitken, J., (1884). "On the formation of small clear spaces in dusty air". Royal Society of Edinburgh, Vol. 32, pp. 239-272.
[35] Zheng, F., (2002). "Thermophoresis of spherical and non-spherical particles: a review of theories and experiments". Advances in Colloid and Interface Science, Vol. 97, pp. 255-278.
[36] Bijan, A., (1984). Convection heat transfer. Third edition, Wily, NewYork.
[37] Patankar, S.V., (1980). Numerical Heat Transfer and Fluid Flow. Second ed, Hemisphere, McGraw-Hill, Washington DC.
[38] غفاری، س، پ. (1391)، مطالعه عددی اثر انتقال نانو ذرات در جریان جابه‌جایی ترکیبی نانو سیال در حفره دو بعدی با درپوش متحرک با خواص متغیر، پایان نامه کارشناسی ارشد، دانشگاه کاشان، کاشان.