Periodic two-dimensional cavity flow: Effect of linear horizontal thermal boundary condition
- Union Carbide Corp., Bound Brook, NJ (USA)
- Rutgers Coll. of Engineering, Piscataway, NJ (USA)
A two-dimensional air-filled cavity with isothermal vertical walls adiabatic top and bottom surfaces has been extensively studied both numerically and experimentally. When the aspect ratio is of order one and the Rayleigh number is less than about 10{sup 9} this geometry produces a highly stable and reproducible laminar flow. The result is quite different when the upper and lower surfaces are subjected to a destabilizing boundary condition, i.e., a linear temperature variation between the hot and cold vertical walls. At a critical Rayleigh number between 10{sup 6} and 10{sup 7} the flow becomes periodic and thus appears to fall into the category of instability of the type known as Hopf bifurcation. Briggs and Jones (1985) report velocity variations measured ner the vertical surfaces that vary by nearly {plus minus} 20% about the mean. Other unexplained behavior reported by Briggs and Jones (1985) consisted of jumps exhibited hysteresis effect, which resulted in some overlap between regimes. This paper presents the results of additional measurements, which indicate that the periodic flow is characterized by the convection of hot and cold pairs of thermals around the enclosure.
- OSTI ID:
- 5416116
- Journal Information:
- Journal of Heat Transfer (Transcations of the ASME (American Society of Mechanical Engineers), Series C); (United States), Vol. 111:1; ISSN 0022-1481
- Country of Publication:
- United States
- Language:
- English
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