3.31 T2.233 Pr0.648 G16.3 ep1.3079 e P700.40 fps8 t40h cc182
167 views · Published 30 September 2014 · 1:07 · Indexed 21 September 2026
Channel: Stephen Morris · 2014 · Science & Technology
The Manchester low temperature convection experiment: Movies of thermal convection in liquid Helium close to absolute zero. The light and dark areas are cold downflows and warm upflows, visualized by passing light through the liquid helium and imaging the resulting "shadowgraph" patterns using a CCD camera which is also at low temperature. Movies provided by Peter Lucas. See the detailed memoir by Peter Lucas in the description of this Flickr album: http://www.flickr.com/photos/nonlin/sets/72157648205587122/ See also A.L. Woodcraft et al, J. Low Temp. Phys., 114, 109 (1999). http://link.springer.com/article/10.1023/A:1021849819891 R.G. Matley et al, Phys. Rev. E 63, 045301(R) (2001), http://link.aps.org/doi/10.1103/PhysRevE.63.045301 M. J. Lees etc al, Phys. Rev. Lett. 93, 144502 (2004) . http://link.aps.org/doi/10.1103/PhysRevLett.93.144502 The movie and image titles give the experimental conditions. The first number is a figure number referred to in the memoir. The other numbers are: T, the temperature of the upper cell boundary in Kelvin; Pr, the Prandtl number of the helium; G, the aspect ratio of the cell; ep, the ratio of the difference between the power applied to the lower boundary and the critical power at the convection threshold to the critical power; e, the ratio of the Rayleigh number minus the critical Rayleigh to the critical Rayleigh number; P the actual power in microwatts; fps the number of frames per second; t, the time period between frames and finally the run number of the image sequence. Note that when fps is 8, this means that the fps was really 24, but each image is shown 3 times to improve the visual effect. Where the data is not available … follows the symbol.
