Abstract
A mathematical model proposed by Bark and Alavyoon for modelling laminar natural convection in electrochemical cells, with binary electrolytes, is extended to simulation of two-dimensional turbulent flows. The turbulence was modelled by a standard k–π model. The constants used in the model are the same as those used by Henkes and Hoogendoorn. Steady state calculations were carried out in a square, differentially heated enclosure for Gr=7×1010 and Pr=0.71. The turbulence model used could not predict the transition effect on the Nusselt number along the hot wall. Transient calculations performed in an enclosure with an aspect ratio of 35, for Gr=6.4×1011 and Sc=2763, revealed large scale fluctuations in the boundary layers near the vertical walls. The model was able to predict qualitatively the velocity field for transitional flow for air induced by buoyancy at Grh=8100 and Grh=22 500. The correlation between the Sherwood and Rayleigh numbers was studied by modelling the mass transfer at the electrodes using a Butler–Volmer law. The computed Sherwood number was found to be approximately proportional to the Rayleigh number to the power of 0.2 in the range of Rah between 5×108 and 1010, and with an order of magnitude of 105.
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A. Eklund, F. Alavyoon, D. Simonsson, R.I. Karlsson and F.H. Bark, Electrochim. Acta 36 (1991) 1345.
F. H. Bark and F. Alavyoon, J. Fluid Mech. 290 (1995) 1.
R. A. Henkes and C. J. Hoogendoorn, Num. Heat Transfer. 28 (1995) 59.
D. Ziegler and J. W. Evans (1986) J. Electrochem. Soc. 133 (1986) 559.
W. P. Jones and B. E. Launder, Int. J. Heat Mass Transfer 15 (1972) 301.
H. Ozoe, A. Mouri, M. Ohmuro, S.W. Churchill and N. Lior, ibid. 28 (1985) 125.
CFX-F3D release 3.3: ‘User Manual’, AEA Technology-Computational Fluid Dynamics Services, Building 8.19, Harwell Laboratory, Oxfordshire OX11 0RA, UK, (1994).
S. V. Patankar and D. B. Spalding, Int. J. Heat Mass Transfer 15 (1972) 1787.
C. M. Rhie and W. L. Chow, Am. Institute of Aeronautics and Astronautics J. 21 (1983) 1527.
P. H. Gaskell and A. K. C Lau, Proceedings of the Conference on ‘Numerical Methods in Laminar and Turbulent Flow’, Montreal (1987).
J. W. Elder, J. Fluid Mech. 23 (1965) 99.
A. Bejan, ‘Convection Heat Transfer’ 2nd edn. Wiley, (J. & Sons, New York, 1995).
J. R. Phillips, Int. J. Heat. Mass Transfer 39 (1996) 2485.
R. Cheesewright, K.J. King and S. Ziai, Proc. ASME Meeting HTD 60 (1986) 75.
R. Cheesewright and S. Ziai, Proceedings of the 8th International Heat Transfer Conference, San Francisco (1986) 1465.
K. J. King, Turbulent Natural Convection in Rectangular Air Cavities, Ph.D. Thesis, Queen Mary College, London, UK (1989).
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Gurniki, F., Bark, F.H. & Zahrai, S. Turbulent free convection in large electrochemical cells with a binary electrolyte. Journal of Applied Electrochemistry 29, 27–34 (1999). https://doi.org/10.1023/A:1003482807773
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DOI: https://doi.org/10.1023/A:1003482807773