Rotational effects on natural convection in a horizontal cylinder

Yang, He; Yang, K. T.; Lloyd, John R.

doi:10.1002/aic.690341006

Cited by 26 publications

(7 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…6). These results are in agreement with those reported in previous works, where different values of the Prandtl number were used [13][14][15]. The continuation method used to follow steady solutions when rotation varies has allowed us to identify a novel result: The existence, for a fixed value of , of two curves of steady primary states.…”

Section: Summary and Concluding Remarkssupporting

confidence: 89%

“…The pioneering work * odalys.sanchez@upc.edu † maria.isabel.mercader@upc.edu ‡ oriol@fa.upc.edu § arantxa@fa.upc.edu of Yang et al [13], aimed at studying crystal growth processes using chemical vapour deposition, establishes clearly the effect of rotation on the basic flow for a horizontal cylinder of aspect ratio 2, with air as working fluid. At low rotational speeds, they observe that rotation tilts the temperature field in the lateral planes as a result of the Coriolis force.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Natural convection in a horizontal cylinder with axial rotation

et al. 2016

View full text Add to dashboard Cite

We study the problem of thermal convection in a laterally heated horizontal cylinder rotating about its axis. A cylinder of aspect ratio = H/2R = 2 containing a small Prandtl number fluid (σ = 0.01) representative of molten metals and molten semiconductors at high temperature is considered. We focus on a slow rotation regime ( < 8), where the effects of rotation and buoyancy forces are comparable. The Navier-Stokes and energy equations with the Boussinesq approximation are solved numerically to calculate the basic states, analyze their linear stability, and compute several secondary flows originated from the instabilities. Due to the confined cylindrical geometry-the presence of lateral walls and lids-all the flows are completely three dimensional, even the basic steady states. Results characterizing the basic states as the rotation rate increases are presented. As it occurred in the nonrotating case for higher values of the Prandtl number, two curves of steady states with the same symmetric character coexist for moderate values of the Rayleigh number. In the range of considered, rotation has a stabilizing effect only for very small values. As the value of the rotation rate approaches = 3.5 and = 4.5, the scenario of bifurcations becomes more complex due to the existence in both cases of very close bifurcations of codimension 2, which in the latter case involve both curves of symmetric solutions.

show abstract

Section: Summary and Concluding Remarkssupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Natural convection in a horizontal cylinder with axial rotation

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The normal gravity is due to an external (vertical) gravity field. Applications include food processing and crystal growth (Yang, Yang & Lloyd 1988). Further, some of the observed flows resemble those in model problems in astrophysical/planetary fluid dynamics (Hide & Mason 1970 ;Hsui, Turcotte & Torrance 1972;Weir 1976).…”

Section: Introductionmentioning

confidence: 86%

Convection in a rotating, horizontal cylinder with radial and normal gravity forces

Ladeinde

Torrance

1991

JFM

View full text Add to dashboard Cite

Convection driven by radial and normal gravity forces in a rotating, horizontal cylinder is examined. The cylinder is subjected to uniform volumetric heating and constant-temperature wall cooling. The parameters are the radial-gravity and normal-gravity Rayleigh numbers, Rar and Rag (with Rar, Rag ≤ 106), the rotational Reynolds number, Re = 2Ω r02/v (0 ≤ Re ≤ 250), and the Prandtl number (Pr = 7). Critical conditions for the radial-gravity rest state correspond to a two-cell flow in the azimuthal plane with Rar,c = 13738. Finite-amplitude transient and steady flows are obtained with a Galerkin finite element method for Rayleigh number ratios in the range 0.1 ≤ Rar/Rag ≤ 100. When radial gravity dominates the flows tend to be multicellular and, during transients, initial high-wavenumber forms evolve to lower-wavenumber forms. When normal gravity dominates the flows are bicellular. When radial and normal gravity forces are comparable, in the presence of rotation, complex time-dependent motions occur and the largest rates of fluid circulation and heat transfer are observed.

show abstract

“…Such applications are encountered in seeking improvements for crystallographic perfection in industrial processing [1,2], food processing [3], heat removal from nuclear reactor fuel rods, double-pipe heat exchangers and underground electric transmission cables using pressurized gas. Quite often the eccentricity results from high angular velocity of the blade or shaft in the rotating machinery or from manufacturing tolerance or thermal deformation in a device of nominally concentric annulus.…”

Section: Introductionmentioning

confidence: 99%