Abstract
The present work is an experimental and a numerical investigation of the turbulent fluid flow and heat transfer in an annular channel between two concentric cylinders with heated stationary outer cylinder (constant heat flux) and adiabatic rotating inner cylinder. Numerically, the governing equations are discretized in a finite volume fashion using a non-staggered (collocated) arrangement of the variables. The solutions were obtained using the SIMPLE algorithm with upwind scheme. A computer program in FORTRAN 90 was build to solve a set of partial differential equations that govern the fluid flow and heat transfer in annular channels. The experimental results are obtained for an inlet air velocity range of 2–6 m/s, for a wall heat flux range of 600–1200 W/m2 and a rotational speed range of inner cylinder of 0–1500 rpm with a gap width of 1.5 cm. Finally, the relationships between the average Nusselt number and the effective Reynolds number for experimental and numerical results were proposed and compared with those in the existing literature.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Abbreviations
- d :
-
Air gap thickness or gap width (m): \({{d} = {r}_{{\rm o}}- {r}_{{\rm i}}}\)
- \({{D}_{{\rm h}}}\) :
-
Hydraulic diameter (m): \({{D}_{{\rm h}} = 2({r}_{{\rm o}}- {r}_{{\rm i}})}\)
- \({{r}_{{\rm o}}}\) :
-
Radius of outer cylinder (m)
- \({{r}_{{\rm i}}}\) :
-
Radius of inner cylinder (m)
- \({{u}_{{\rm in}}}\) :
-
Inlet air velocity (m/s)
- N :
-
Rotation speed of inner cylinder (rpm)
- L :
-
Length (m)
- \({{k}_{{\rm a}}}\) :
-
Air thermal conductivity \({({\rm W/m}^{2} \,^{\circ} {C})}\)
- \({{q}_{{\rm w}}}\) :
-
Wall heat flux (W/m2)
- \({\overline {{T}_{\rm s}}}\) :
-
Average surface temperature of outer cylinder \({(^{\circ} {\rm C})}\)
- \({\overline{{T}_{\rm a}}}\) :
-
Average air temperature \({(^{\circ} {\rm C})}\)
- P :
-
Pressure (N/m2)
- k :
-
Turbulent kinetic energy (m2/s2)
- \({\overline{{Nu}}}\) :
-
Average Nusselt number: \({\overline{{Nu}} = {q}_{{\rm w}}{D}_{{\rm h}} /(\overline {{T}_{{\rm w}} }-\overline{{T}_{{\rm a}} } ) {k}_{{\rm a}}}\)
- Pr :
-
Prandtl number: \({\Pr = \mu{C}_{{\rm p}} / {k}_{{\rm a}}}\)
- \({{Re}_{{\rm a}}}\) :
-
Axial Reynolds number: \({{Re}_{{\rm a}}=\rho \,\,{u}_{{\rm in}}{D}_{{\rm h}}/ \mu}\)
- \({{Re}_{{\rm r}}}\) :
-
Rotational Reynolds number: \({{Re}_{{\rm r}}=\rho\,\, {r}_{{\rm i}} \varOmega {D}_{{\rm h} }/ \mu}\)
- \({{u}_{{\rm eff }}}\) :
-
Effective velocity (m/s): \({{u}_{{\rm eff}} = [ {u}_{{\rm in}}^{2 }+ ({r}_{{\rm i}} \varOmega / 2)^{2 }]^{0.5}}\)
- \({{Re}_{{\rm eff}}}\) :
-
Effective Reynolds number: \({{Re}_{{\rm eff}}=\rho\,\,{u}_{{\rm eff}} {D}_{{\rm h}}/ \mu}\)
- μ :
-
Dynamic viscosity (N s/m2)
- \({\mu_{{\rm t}}}\) :
-
Turbulent viscosity (N s/m2)
- \({\varOmega}\) :
-
Angular velocity of inner cylinder (rad/s): \({\varOmega {=} 2 \pi {\rm N} / 60}\)
- \({\rho}\) :
-
Density (kg/m3)
- \({\varepsilon}\) :
-
Turbulent energy dissipation rate (m2/ s2)
- \({\varGamma}\) :
-
General exchange coefficient
- a:
-
Axial
- r:
-
Rotational
- eff:
-
Effective
- w:
-
Wall
- in:
-
Inlet
- t:
-
Turbulent
- o:
-
Outer
- i:
-
Inner
References
Gazley C.: Heat transfer characteristics of the rotation and axial flow between concentric cylinders. J. Heat Transf. 80, 79–90 (1985)
Kuzay, T.M.: Turbulent heat and momentum transfer studies, Ph.D. Thesis, University of Minnesota, (1973)
Pfitzer H., Beer H.: Heat Transfer in an annulus between independently rotating tubes with turbulent axial flow. Int. J. Heat Mass Transf. 35, 623–633 (1992)
Smyth, R.; Zurita, P.: Heat transfer at the outer surface of a rotating cylinder in the presence of axial flow, Trans. Eng. Sci. 5 (1994)
Escudier M.P., Gouldson I.W.: Concentric annular flow with center body rotation of a Newtonian and a shear- thinning liquid. Int. J. Heat Fluid Flow 16, 156–162 (1995)
Char M.I., Hsu Y.H.: Numerical prediction of turbulent mixed convection in a concentric horizontal rotating annulus with low-re two-equation models. Int. J. of Heat and Mass Transfer 41, 1633–1643 (1998)
Tzeng S.C.: Heat transfer in a Small Gap between Co-Axial Rotating Cylinders. Int. Commun. Heat Mass Transf. 33, 737–743 (2006)
Ouali S.S., Saury D., Harmand S., Laloy O.: Convective heat transfer inside a rotating cylinder with an axial air flow. Int. J. Therm. Sci. 45, 1166–1178 (2006)
Sukumaran, A.K.; Santhosh, K.S.: Numerical simulation of heat transfer and fluid flow in rotating annulus, In: National Conference on Technological Trends, (2009)
Nili-Ahmadabadi M., Karrabi H.: Heat transfer and flow region characteristics study in a non-annular channel between rotor and stator. Therm. Sci. 16, 593–603 (2012)
Hadziabdic M., Hanjalic K., Mullyadzhanov R.: LES of turbulent flow in a concentric annulus with rotating outer wall. Int. J.Heat Fluid Flow 43, 74–84 (2013)
Fénot M., Bertin Y., Dorignac E., Lalizel G.: A review of heat transfers between concentric rotating cylinders with or without axial flow. Int. J. Therm. Sci. 50, 1138–1155 (2011)
Launder B.E., Spalding D.B.: The numerical computation of turbulent flow. Comp. Methods Appl. Mech. Eng. 3, 269 (1974)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jalil, J.M., Hanfash, AJ.O. & Abdul-Mutaleb, M.R. Experimental and Numerical Study of Axial Turbulent Fluid Flow and Heat Transfer in a Rotating Annulus. Arab J Sci Eng 41, 1857–1865 (2016). https://doi.org/10.1007/s13369-015-1909-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13369-015-1909-1