The effects of buoyancy on the critical heat flux in forced convection
- Michigan Univ., Ann Arbor (United States)
The critical heat flux (CHF) in forced convection over a flat surface at relatively low flow velocities has been found, not unexpectedly, to depend upon the orientation of the buoyancy. The CHF for R-113 was measured at various heating surface orientations for test section Reynolds numbers ranging between 3000 and 6500. In this flow range, the buoyancy force acting on the vapor generally dominates over the flow inertia, yet the inertia would still be substantial were gravity to be reduced. In the experiments of this study, the CHF is determined for heating surface orientations ranging from 0 deg to 360 deg, for flow velocities between 4 cm/s and 35 cm/s, and for subcoolings between 2.8 C and 22.2 C. The results presented here demonstrate the strong influence of buoyancy at low flow velocities, which diminishes as the flow velocity and subcooling are increased. 15 refs.
- Research Organization:
- National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
- OSTI ID:
- 6457599
- Report Number(s):
- AIAA-Paper-93-0575; CONF-930108-; CNN: NAG3-589
- Resource Relation:
- Conference: 31. American Institute of Astronautics and Aeronautics (AIAA) aerospace sciences meeting, Reno, NV (United States), 11-14 Jan 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
The role of buoyancy orientation on bubble residence times and the related critical heat flux
Stabilization of buoyancy-driven unstable vortex flow in mixed convection of air in a rectangular duct by tapering its top plate