Abstract
This work presents a computational study to compare heat transfer processes and flow behavior of the bed among different regimes of fluidized bed reactors with fixed, bubbling, and slugging flow regimes. Sand particles with a mean diameter of 550 μm were used as a bed material fluidized by air. Wall-to-bed heat transfer and fluidization behavior were studied at different inlet velocities to represent different flow regimes. A two-phase model with kinetic theory of granular flow was used to simulate both heat transfer and flow characteristics. Simulation findings were validated by comparing them with available experimental results, in which there was good agreement. The obtained results demonstrated that the gas-solid heat transfer and wall-to-bed heat transfer processes strongly depend on the bed flow structure, especially void and solid volume fractions. Slugging beds related to the highest inlet velocity achieved the best conditions of a heat transfer process, as indicated by the highest gas-solid and wall-to-bed heat transfer coefficients. Simulation results also showed that slugging behavior had no negative effect on the heat transfer process despite problems such as obstruction and entrainment.
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References
C. Dechsiri, Particle transport in fluidized beds: experiments and stochastic models, Ph.D. Thesis, Groningen: s.n. (2004).
R. K. Thapa, C. Pfeifer and B. M. Halvorsen, Flow regime identification in a fluidized bed combustion reactor, International Journal of Modeling and Optimization, 6 (3) (2016) 188–194.
Y. Dong, B. Sosna, O. Korup, F. Rosowski and R. Horn, Investigation of radial heat transfer in a fixed-bed reactor: CFD simulations and profile measurements, Chemical Engineering Journal, 317 (2017) 204–214.
Z. Minhua, D. He and G. Zhongfeng, Computational study of flow and heat transfer in fixed beds with cylindrical particles for low tube to particle diameter ratios, Chemical Engineering Research and Design Journal (2018) Doi: https://doi.org/doi:10.1016/j.cherd.2018.01.006.
Y. Zhang and Q. Wei, CPFD simulation of bed-to-wall heat transfer in a gas-solids bubbling fluidized bed with an immersed vertical tube, Chemical Engineering and Processing, 116 (2017) 17–28.
C. C. Pain, S. Mansoorzadeh and C. R. E. de Oliveira, A study of bubbling and slugging fluidized beds using the two-fluid granular temperature model, International Journal of Multiphase Flow, 27 (2001) 527–551.
H. M. Abdelmotalib, M. A. M. Youssef, A. A. Hassan, S. B. Youn and I.-T. Im, Influence of the specularity coefficient on hydrodynamics and heat transfer in a conical fluidized bed combustor, International Communications in Heat and Mass Transfer, 75 (2016) 169–176.
S. V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere, Washington, D.C. (1980).
H. M. Abdelmotalib, M. A. M. Youssef, A. A. Hassan, S. B. Youn and I.-T. Im, Numerical study on the wall to bed heat transfer in a conical fluidized bed combustor, International Journal of Precision Engineering and Manufacturing, 16 (7) (2015) 1551–1559.
H. M. Abdelmotalib, D. G. Ko and I.-T. Im, A study on wall-to-bed heat transfer in a conical fluidized bed combustor, Applied Thermal Engineering, 99 (2016) 928–937.
H. M. Abdelmotalib, J. S. Kim and I.-T. Im, A study on heat transfer in a conical fluidized-bed reactor with an immersed cylindrical heater, Numerical Heat Transfer, Part A: Applications, 71 (2017) 855–866.
M. Syamlal and J. O'Brien, Derivation of a Drag Coefficient from Velocity-Voidage Correlations, US Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory, Morgantown, WV (1987).
C. Lun, S. Savage, D. Jeffrey and N. Chepurniy, Kinetic theories for granular flow: Inelastic particles in couette flow and slightly inelastic particles in a general flow field, Journal of Fluid Mechanics, 140 (1984) 223–256.
S. Chapman and T. Cowling, The Mathematical Theory of Non-Uniform Gases, 3rd ed., Cambridge University Press, Cambridge, UK (1970).
D. Gunn, Transfer of heat or mass to particles in fixed and fluidized beds, International Journal of Heat Mass Transfer, 21 (1978) 467–476.
P. Zehner and E. Schlünder, Wärmeleitfähigkeit von schüttingen bei mässigen Temperaturen, D. Chem. Eng. Tech., 42 (1970) 933–941.
H. T. Bi and J. R. Grace, Flow regime maps for gassolids fluidization and upward transport, International Journal of Multiphase Flow, 21 (1995) 1229–1236.
R. K. Singh and G. K. Roy, Prediction of minimum slugging velocity, bubbling bed index and range of bubbling fluidization in cylindrical and non-cylindrical gas-solid fluidized beds, Indian Journal of Chemical Technology, 15 (2008) 85–89.
H. M. Abdelmotalib and I.-T. Im, A study on the particle temperature in a conical fluidized bed using infrared thermography, Journal of Mechanical Science and Technology, 32 (9) (2018) 4529–4534.
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This paper was supported by research funds of Jeonbuk National University in 2018.
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Byung Moon So
graduated Wonkwang University and received his Ph.D. in Electrical Engineering from Kwangwoon University in 1988. After that he was doing his research at Osaka Prefecture University for a year as a visiting researcher. His research interests are materials for electrical and heat insulation.
Hamada M. Abdelmotalib
received the B.S. and M.S. in Mechanical Engineering from Minia University, Minia, Egypt in 2006 and 2011, respectively, and the Ph.D. from Jeonbuk National University, Korea in 2016. In 2016, he joined the Department of Mechanical Power and Energy, Faculty of Engineering, Minia University as a lecturer. His main reserash fields are numerical modeling, fluidization, heat transfer, Combustion, and pyrloysis.
Mohamed Yahya Hashim
received his Master degree at Heat Transfer and Reactive Flow Lab. of Jeonbuk National University. He is currently a Ph.D. candidate at Fluid Engineering Lab., Jeonbuk National University. His research focuses on swirling flow and acoustic analysis of gas turbine combustors.
Ik-Tae Im
graduated Hanyang University, Seoul, Korea in 1993 and received the M.S. and Ph.D. in mechanical engineering from the same university, in 1995 and 1999, respect-tively. In 1999, he joined the Department of Mechanical Design Engineering at Jeonbuk National University as a Senior Lecturer. His research interests are on heat transfer problems with reactive flow such as FBR and thin film deposition.
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So, B.M., Abdelmotalib, H.M., Hashim, M.Y. et al. Computational study on heat transfer and bed flow according to different regimes of fluidized beds. J Mech Sci Technol 33, 5881–5887 (2019). https://doi.org/10.1007/s12206-019-1133-0
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DOI: https://doi.org/10.1007/s12206-019-1133-0