پیوندهای مفید
آمار
| تعداد نشریات | 21 |
| تعداد شماره‌ها | 628 |
| تعداد مقالات | 9,179 |
| تعداد مشاهده مقاله | 67,526,988 |
| تعداد دریافت فایل اصل مقاله | 8,061,732 |
مطالعه انتقال حرارت از دیواره بستر حبابی گاز-جامد به ذرات جامد درون آن به کمک دینامیک سیالات محاسباتی | ||
| مدل سازی در مهندسی | ||
| مقاله 10، دوره 14، شماره 46، مهر 1395، صفحه 123-136 اصل مقاله (1.64 M) | ||
| شناسه دیجیتال (DOI): 10.22075/jme.2017.1780 | ||
| نویسندگان | ||
| حسین حسینی* 1؛ اشکان محصلی2 | ||
| 1دانشگاه ایلام | ||
| 2دانشگاه ماهشهر | ||
| تاریخ دریافت: 17 دی 1393، تاریخ بازنگری: 02 اردیبهشت 1394، تاریخ پذیرش: 02 اردیبهشت 1394 | ||
| چکیده | ||
| بسترهای سیال به دلیل خصوصیات انتقال حرارتی مناسب در بسیاری از فرایندهای حرارتی استفاده میشوند. به دلیل پیچیدگیهای مربوط به مدلسازی انتقال حرارت در بسترهای سیال، پژوهشهای محدودی در این خصوص صورت گرفته است. در تحقیق موجود با استفاده از مدل دو سیالی ترکیب با تئوری جنبشی جریان دانهای یک راکتور گاز-جامد حبابی حاوی ذرات کروی با قطر میانگین 280 میکرون شبیهسازی شده است. تاثیر دو مدل دراگ مهم یعنیGidaspow و Syamlal-O’Brien و برخی پارامترهای هیدرودینامیکی همچون ضریب ارتجاع ذره-ذره و نیز تاثیر شرایط مرزی ذره-دیواره بررسی شده است. نتایج شبیهسازی حاکی از این است که هر دو مدل دراگ، عبور حباب از درون بستر را بخوبی نشان میدهند. اگرچه هر دو مدل دراگ روند تغییرات محلی ضریب انتقال حرارت با زمان را بطور مناسبی پیشبینی میکنند، اما مدلGidaspow انطباق بهتری را نتایج تجربیِ ضریب انتقال حرارت از دیواره به بستر را نشان میدهد. همچنین دیده شده که ضرایب ارتجاع ذره-ذره و ذره-دیواره و نیز ضریب آینهای تاثیر بسزایی بر انتقال حرارت درون بستر گاز-جامد حبابی دارند. | ||
| کلیدواژه‌ها | ||
| انتقال حرارت؛ KTGF؛ CFD؛ مدل دو سیالی؛ مدل دراگ؛ ضریب آینه ای | ||
| عنوان مقاله [English] | ||
| Numerical Study of Wall-to-Bed Heat Transfer in a GasâSolid Bubbling Fluidized Bed by CFD | ||
| نویسندگان [English] | ||
| Hossein Hosseini1؛ Ashkan Mohasseli2 | ||
| چکیده [English] | ||
| Due to the effective heat transfer in fluidized beds, these systems have been wieldy used in many thermal processes. There are limited published papers in the literature regarding heat transfer in fluidized beds, because of complexities existing in these systems. In the present study, a gas-solid bubbling fluidized bed including the spherical particles with diameter of 280 µm is simulated by a Eulerian-Eulerian Two-Fluid Model incorporating the kinetic theory of granular flow (KTGF). Influence of two important drag models of Gidaspow and Syamlal as well as some hydrodynamics parameters, namely, particle-particle restitution coefficient and solid wall boundary conditions are studied. Both drag models predict the behavior of the bubble passage through the bed reasonably. Although both drag functions show the same trend with the experimental data, Gidaspow drag model predicts the better results than the Syamlal one. The CFD results reveal that the modeling parameters of specularity coefficient, particle-particle and particle-wall restitution coefficients have a significant effect on the heat transfer coefficient between the wall and particles. | ||
| کلیدواژه‌ها [English] | ||
| Heat transfer, CFD, KTGF, TFM, Drag model, specularity coefficient | ||
| مراجع | ||
|
[1] Berruti, F., Chaouki, J., Godfroy, L., Pugsley, T., Patience, G. (1995). Hydrodynamics of circulating fluidized bed risers: a review, The Canadian Journal of Chemical Engineering, vol. 73, pp. 579– 602. [2] Armstrong, L., Luo, K., Gu, S. Three-dimensional modelling on the hydrodynamics of a circulating fluidised bed, in: Proceedings of the Inaugural US-EU- China Thermophysics Conference, Beijing, China. [3] Kuipers, J.A.M., Prins, W., van Swaaij, W.P.M. (1992). Numerical calculation of wall-to-bed heat transfer coefficients i gas-fluidized beds. AIChE J., vol. 38, pp. 1079-1091. [4] Patil, D., Smit, J., van Sint Annaland, M., Kuipers, J.A.M. (2006). Wall-to-bed heat transfer in gas- solid bubbling fluidized beds, AIChE J., vol. 52, pp. 58–74. [5] Samuelsberg, A., Hjertager, B. (1995). An experimental and numerical study of flow patterns in a circulating fluidized bed reactor, International Journal of Multiphase Flow, vol. 22, pp. 575–591. [6] Almuttahar, A., Taghipour F. (2008). Computational fluid dynamics of high density circulating fluidized bed riser: study of modelling parameters, Powder Technology, vol. 185, pp. 11–23. [7] Patil, A. V., Peters, E.A.J.F., Kolkman, T., Kuipers J.A.M. (2014). Modeling bubble heat transfer in gas–solid fluidized beds using DEM, Chemical Engineering Science, vol. 105, pp. 121–131. [8] Oevermann, M., Gerber, S., Behrendt F. (2009). Euler–Lagrange/DEM simulation of wood gasification in a bubbling fluidized bed reactor, Particuology, vol. 7, pp. 307–316. [9] Behjat, Y., Shahhosseini, S., Hashemabadi, S. H. (2008). CFD modeling of hydrodynamic and heat transfer in fluidized bed reactors, International Communications in Heat and Mass Transfer, vol. 35, 357–368. [10] Chang, J., Wang, G., Gao, J., Zhang, K., Chen, H., Yang, Y. (2012). CFD modeling of particle–particle heat transfer in dense gas-solid fluidized beds of binary mixture, Powder Technology, vol. 217, pp. 50–60. [11] Dehnavi, M. A., Shahhosseini, S., Hashemabadi, S. H., Ghafelebashi, S. M. (2010). CFD simulation of hydrodynamics and heat transfer in gas phase ethylene polymerization reactors, International Communications in Heat and Mass Transfer, vol. 37, pp. 437–442. [12] Schmidt, A., Renz, U. (1999). Eulerian computation of heat transfer in fluidized beds, Chemical Engineering Science, vol. 54, pp. 5515–5522. [13] Armstrong, L.M., Gu, S., Luo, K.H. (2010). The influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed, International Journal of Multiphase Flow, vol. 36, pp. 916–929. [16] Armstrong, L.M., Gu, S., Luo, K.H. (2010). Study of wall-to-bed heat transfer in a bubbling fluidised bed using the kinetic theory of granular flow, International Journal of Heat and Mass Transfer, vol. 53, pp. 4949–4959. [14] Gidaspow, D., Bezburuah, R., Ding, J. Hydrodynamics of circulating fluidized beds: kinetic theory approach, in: Proceedings of the 7th Fluidization Conference. [15] Syamlal, M., O’Brien, T. Derivation of a drag coefficient from velocity voidage correlation, in: US Dept. of Energy, Office of Fossil Energy, National Energy Technology Laboratory, Morgantown, West Virginia April. [17] Savage, S., Jeffrey, D. (1981). The stress tensor in a granular flow at high shear rates, Journal of Fluid Mechanics, vol. 110, pp. 255–272. [18] Jenkins, J., Savage, S. (1983). A theory for the rapid flow of identical, smooth, nearly elastic, spherical particles, Journal of Fluid Mechanics, vol. 130, pp. 187–202. [19] Savage, S. (1983) Granular flows at high shear rates, in: R.E. Meyer (Ed.), Theory of Dispersed Multiphase Flow, Academic Press, New York. [20] Hosseini, S.H., Ahmadi, G., Saeedi Razavi, B., Zhong, W. (2010). Computational fluid dynamic simulation of hydrodynamic behavior in a two-dimensional conical spouted bed, Energy Fuels, vol. 24, pp. 6086–6098. [21] Hosseini, S.H., Ahmadi, G., Olazar, M. (2013). CFD simulation of cylindrical spouted bed by the kinetic theory of granular flow, Powder Technology, vol. 246, pp. 303–316. [22] Hosseini, S.H., Ahmadi, G., Olazar, M. (2014). CFD study of particle velocity profiles inside a draft tube in a cylindrical spouted bed with conical base, Journal of the Taiwan Institute of Chemical Engineers, vol. 45, pp. 2140–2149. [23] Hosseini, S.H. (2014). Influences of geometric factors on CFD results of a draft tube cylindrical spouted bed, Progress in Computational Fluid Dynamics: An International Journal, Accepted paper. [24] Ding J., Gidaspow, D. (1990). A bubbling fluidization model using kinetic theory of granular flow, AIChE J, vol. 36, pp. 523–538. [25] Gidaspow, D., Bezburuah, R., Ding, J. (1992). Hydrodynamics of circulating fluidized beds, kinetic theory approach. In Fluidization VII, Proceedings of the 7th Engineering Foundation Conference on Fluidization, 75–82. [26] Schaeffer, D. (1987). Instability in the evolution equations describing incompressible granular flow, Journal of Differential Equations, vol. 66, pp. 19–50. [27] Syamlal, M., Rogers, W., O’Brien, T. J. (1993). MFIX Documentation: Volume1, Theory Guide. National Technical Information Service, Springfield, VA. DOE/METC-9411004, NTIS/DE9400087. [28] Lun, C. K. K., Savage, S. B., Jeffrey, D. J., Chepurniy, N. (1984). Kinetic theories for granular flow: inelastic particles in couette flow and slightly inelastic particles in a general flow field, Journal of Fluid Mechanics, vol. 140, pp. 223–256. [29] Ogawa, S., Umemura, A., Oshima, N. (1980). On the equation of fully fluidized granular materials, Journal of Applied Mathematics and Physics, vol. 31, pp. 483–493. [30] Gunn, D. (1978). Transfer of heat or mass to particles in fixed and fluidised beds, International Journal of Heat and Mass Transfer, vol. 21, pp. 467–476. [31] Sinclair, J., Jackson, R. (1989). Gas-particle flow in a vertical pipe with particle-particle interactions, AIChE J., vol. 35, pp. 1473 –1486. [32] Vasquez, S., Ivanov, V. (2000). A phase coupled method for solving multiphase problems on unstructured meshes, in: Proceedings of ASME FEDSM’00: ASME 2000 Fluids Engineering Division Summer Meeting, Boston. [33] Pain, C. C., Mansoorzadeh, S., de Oliveira, C. R. E., Goddard, A. J. H. (2001). Numerical modelling of gas–solid fluidized beds using the two-fluid approach, International Journal for Numerical Methods in Fluids, vol. 36, 91–124. [34] Pain, C. C., Mansoorzadeh, S., de Oliveira, C. R. E. (2001). A study of bubbling and slugging fluidised beds using the two-fluid granular temperature model, International Journal of Multiphase Flow, 27, pp. 527–551. [35] Liu, G.-Q., Li, S.-Q., Zhao, X.-L., Yao, Q. (2008). Experimental studies of particle flow dynamics in a two-dimensional spouted bed, Chemical Engineering Science, 63, pp. 1131–1141.
| ||
|
آمار تعداد مشاهده مقاله: 1,908 تعداد دریافت فایل اصل مقاله: 1,014 |
||