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Experimental analysis of thermal fields in horizontally eccentric cylindrical annuli

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Abstract

This paper presents new experimental results on thermal field and heat transfer in a two-dimensional annulus between horizontally eccentric cylinders. The study is conducted by means of optical techniques, for 1.07×104≤Ra L≤8.27×104 and a wide eccentricity range. The horizontal eccentricity of the inner cylinder substantially alters the thermal field and the geometry of the plume, but, in analogy to the behaviour for vertical eccentricity, the average Nu is slightly affected in the investigated range of eccentricity. The concentric geometry is also considered mainly to validate the experimental technique and evaluate the accuracy of the adopted methodology by comparison with available results. Both shearing interferometer and reference beam interferometer are obtained by means of Wollaston prisms with appropriate splitting angles, so that the temperature and local Nu distributions may be evaluated quantitatively from the original pictures via digital image processing.

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Abbreviations

B :

reference length (m)

b :

length of test section (m)

d :

separation (m)

D :

diameter of cylinder (m)

E :

dimensional eccentricity (m)

e :

E/L = dimensionless eccentricity

F :

luminance (W/m2)

f :

focal distance (m)

g :

gravity acceleration (m/s2)

Gr L :

Grashof number

H :

matricial mask

h :

radii ratio

k :

Gladstone-Dale constant (m3/kg)

k eq :

local equivalent conductivity

L :

gap (m)

Nu :

Nusselt number

R :

radius of inner cylinder (m)

r :

radial coordinate (m)

Ra L :

Rayleigh number

T :

temperature (°C)

x i :

coordinate (m)

α :

thermal diffusivity (m2/s)

β :

thermal expansion coefficient (°C-1)

Δρ :

density variation (kg/m3)

ΔT :

temperature jump (°C)

δ :

dirac delta function

ɛ :

divergence angle in degrees

θ :

azimuthal coordinate in degrees

λ :

wave length of light (m)

ν :

kinematic viscosity (m2/s)

ρ :

density (kg/m3)

cond:

conductive

c :

filtered quantity

i :

inner

m :

mean value

o :

outer

References

  • Behnia, M.; de Vahl Davis, G.; Stella, F.; Guj, G. 1990: A comparison of velocity-vorticity and stream function vorticity formulations for Pr = 0. Notes on Num. Fluid Mech. GAMM Workshop 27, 19–24

    Google Scholar 

  • Carlomagno, G. M. 1986: Metodi ottici quantitavi nella diffusione di massa e di energia. UIT Atti del 4° Congresso nazionale sulla trasmissione del calore, June 5–7, Genova, Italy

  • Chakrabarti, S.; Probert, S. D.; Shilton, M. J. 1983: Optimal eccentrical annuli (containing atmospheric-pressure air) for thermally insulating, horizontal, relatively cold pipes. Appl. Energy, 14, 257–293

    Google Scholar 

  • Cho, C. H.; Chang, K. S.; Park, K. H. 1982: Numerical simulation of natural convection in concentric and eccentric horizontal cylindrical annuli. J. Heat Transfer 104, 624–630

    Google Scholar 

  • Grigull, U.; Hauf, W. 1966: Natural convection in horizontal cylindrical annuli. Proc. of the 3rd Heat Transfer Conf. Chicago, Paper 60, 182–195

  • Kuehn, T. H.; Goldstein, R. J. 1976: An experimental and theoretical study of natural convection in the annulus between horizontal concentric cylinders. J. Fluid Mech. 74, 695–719

    Google Scholar 

  • Kuehn, T. H.; Goldstein, R. J. 1978: An experimental and theoretical study of natural convection heat transfer in concentric and eccentric horizontal cylindrical annuli. J. Heat Transfer 100, 635–640

    Google Scholar 

  • Merzkirch, W. 1974: Flow visualization. London: Academic Press, Wiley, pp. 115–231

    Google Scholar 

  • Pratt, W. K. 1978: Digital image processing. New York: Wiley, pp. 307–513

    Google Scholar 

  • Projahn, U.; Rieger, H.; Beer, H. 1981: Numerical analysis of laminar natural convection between concentric and eccentric cylinders. Num. Heat Transfer 4, 131–146

    Google Scholar 

  • Stella, F.; Guj, G. 1989: Vorticity-velocity formulation in the computation of flows in mutliconnected domains. Int. J. Num. Meth. Fluids 9, 1285–1298

    Google Scholar 

  • Wang, Y. Z.; Bau, H. H. 1988: Low Rayleigh number convection in horizontal eccentric annuli. Phys. Fluids 31, 2467–2473

    Google Scholar 

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Authors and Affiliations

  1. Università di Roma “La Sapienza” Via Eudossiana, 18 I-00184, Rome, Italy

    G. Guj, S. Iannetta & G. Moretti

Authors
  1. G. Guj
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  2. S. Iannetta
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  3. G. Moretti
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Guj, G., Iannetta, S. & Moretti, G. Experimental analysis of thermal fields in horizontally eccentric cylindrical annuli. Experiments in Fluids 12, 385–393 (1992). https://doi.org/10.1007/BF00193885

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  • DOI: https://doi.org/10.1007/BF00193885

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