Mixed convection flow and heat transfer in entrance region of rectangular ducts rotating about a parallel axis
Book
·
OSTI ID:458431
- Chung Cheng Inst. of Tech., Taoyuan (Taiwan, Province of China). Dept. of Aeronautical Engineering
- Hua Fan Coll. of Humanities and Technology, Taipei (Taiwan, Province of China). Dept. of Mechanical Engineering
The objective of the present work is to investigate the laminar mixed convection flow and heat transfer in the entrance region of heated rectangular ducts rotating about a parallel axis. Heating conditions of isothermal and iso-flux are both considered. Boussinesq approximation is invoked to take into account buoyancy effect induced by centrifugal force. Navier-Stokes/Boussinesq system can be cast into a dimensionless form, in which five governing parameters, the Prandtl number Pr, rotational Reynolds number J, rotational Grashof number Gr{sub {Omega}}, aspect ratio {gamma} and the eccentricity E, are involved. Mechanisms of secondary vortex development in the ducts are explored by a theoretical analysis on vorticity transport equation. The values of Pr and E are fixed as 0.7 and 10, respectively. For various combinations of the other thee parameters, a vorticity-velocity method implemented with a marching technique is employed to solve the resultant three-dimensional system for simultaneously developing flow and temperature fields. The emphasis is placed on the rotational effects, including both coriolis force and centrifugal buoyancy; on the non-isothermal flow and the related heat transfer. The results reveal that the friction factors and heat transfer rates can be enhanced by Coriolis and rotation-induced buoyancy effects; and the variations of the local values are closely related to the evolution of the secondary vortices in ducts. The differences in flow behaviors and thermal characteristics for UWT and UHF are also investigated by the present theoretical analysis on secondary flow mechanism as well as the computational results.
- Sponsoring Organization:
- National Science Council, Taipei (Taiwan, Province of China)
- OSTI ID:
- 458431
- Report Number(s):
- CONF-951135--; ISBN 0-7918-1751-2
- Country of Publication:
- United States
- Language:
- English
Similar Records
An experimental study of convective heat transfer in radially rotating rectangular ducts
Numerical study of secondary flows in curved ducts
Mixed convection heat and mass transfer in radially rotating rectangular ducts
Journal Article
·
Thu Aug 01 00:00:00 EDT 1991
· Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States)
·
OSTI ID:5697061
Numerical study of secondary flows in curved ducts
Thesis/Dissertation
·
Thu Dec 31 23:00:00 EST 1987
·
OSTI ID:5236932
Mixed convection heat and mass transfer in radially rotating rectangular ducts
Journal Article
·
Thu Nov 26 23:00:00 EST 1998
· Numerical Heat Transfer. Part A, Applications
·
OSTI ID:302322