Pseudosteady-state mixed convection inside rotating spherical containers
A computational study of the pseudosteady-state two-dimensional mixed convection within rotating spherical containers is presented. The computations are based on an iterative, finite-volume numerical procedure using primitive dependent variables, whereby the time-dependent continuity, momentum and energy equations in the spherical coordinate system are solved. Natural convection effect is modeled via the Boussinesq approximation. For a fixed Prandtl number of 4.62, parametric studies were performed by varying the Rayleigh number in order to cover the laminar regime adequately. For a given Rayleigh number, the ratio of Gr/Re{sup 2} was varied between 0.1 and 10. Given a Rayleigh number, the streamline patterns maintain their general shape with a dominant rotating vortex. As the forced convection effect becomes less marked, the streamlines exhibit less pronounced gradients near the surface of the sphere. As the rotational effect become more marked, the extent of the deviation from the limiting case of non-rotating spheres becomes more noticed. However, the bottom of the sphere still remains to be the region with enhanced heat transfer. Given a rotational Reynolds number, the streamline patterns are not affected greatly as the natural convection is promoted, however the temperature gradients near the surface are markedly enhanced. It is noticed that as natural convection effects are promoted, the greater portion of the sphere's surface experiences enhanced heat transfer rates. Given a Rayleigh number, the contours of the azimuthal velocity exhibit a nearly vertical equally-spaced pattern suggesting that solid-body rotation for high rotational Reynolds numbers. However, as the natural convection effects are enhanced, the contours become more slanted. The variation of the mean Nusselt number with the Reynolds and Rayleigh numbers is also quantified.
- Research Organization:
- Auburn Univ., AL (US)
- OSTI ID:
- 20030476
- Resource Relation:
- Conference: 5th ASME/JSME Thermal Engineering Joint Conference, San Diego, CA (US), 03/14/1999--03/19/1999; Other Information: 1 CD-ROM. Operating system required: Windows i386(tm), i486(tm), Pentium (R) or Pentium Pro, MS Windows 3.1, 95, or NT 3.51, 8 MB RAM, MacIntosh and Power MacIntosh with a 68020 or greater processor, System software version 7.1, 3.5 MB RAM (5 MB for PowerMac) 6 MB available hard-disk space, Unix; PBD: 1999; Related Information: In: Proceedings of the 5th ASME/JSME thermal engineering joint conference, [3600] pages.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Equatorial symmetry of Boussinesq convective solutions in a rotating spherical shell allowing rotation of the inner and outer spheres
Analysis of cross-flow mixed convection with applications to building heat transfer