Abstract
The Rayleigh number at which steady convective flow changes to time-dependent flow is determined experimentally for several fluids with Prandtl numbers from 1 to 104. The time dependence is of two forms: (i) a slow tilting of the cell boundary, with time scale of the vertical thermal diffusion time, (ii) an oscillation with a faster time scale determined by the orbit time of the fluid around the cell. The nature of this oscillation is one of hot (or cold) spots advected with the original cellular motion. At a fixed point in the fluid this produces a time periodic oscillation of the temperature. A discrete change of slope of the heat flux curve accompanies this transition. As the Rayleigh number is increased, transition to disorder is seen to result from an increase in the frequency and number of these oscillations.
Publisher
Cambridge University Press (CUP)
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics
Reference9 articles.
1. Silveston, P. L. 1958 Forch. Ing. Wes. 24, 29–32, 59–69.
2. Malkus, W. V. R. 1954b Proc. Roy Soc. A225, 196–212.
3. Willis, G. E. & Deardorff, J. W. 1967 Phys. Fluids,10,931–937.
4. Howard, L. N. 1966 Proceedings of the Eleventh International Congress on Applied Mechanics ,1109–1115.Berlin:Springer.
5. Krishnamurti, R. 1970 J. Fluid Mech. 42,29.
Cited by
251 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献