Fuck Yeah Fluid Dynamics

Celebrating the physics of all that flows. Ask a question, submit a post idea or send an email. You can also follow FYFD on Twitter and Google+. FYFD is written by Nicole Sharp, PhD.

Recent Tweets @

If you make a proper cup of hot chocolate this holiday, watch carefully and you just may catch some Rayleigh-Benard convection like the video above. (Note, video playback is 3x.) The canonical Rayleigh-Benard problem is one in which fluid is heated from below and cooled from above. For the cup of hot chocolate, the cooling comes from the colder, ambient air at the cocoa’s surface. Because cooler fluid is denser than warmer fluid, the cocoa near the surface will tend to sink down, allowing warmer cocoa to rise. As that warm cocoa reaches the surface, it too will cool and sink back down, continuing the cycle. The effect relies on buoyancy and, by extension, gravity; on the International Space Station, for example, astronauts would not observe such convection. The distinctive shape of the cells depends on the boundaries of the cup. This post is part of our weeklong holiday-themed fluid dynamics series. (Video credit: Armuotas)

  1. dim-my-eyes reblogged this from fuckyeahfluiddynamics
  2. cindayday reblogged this from scinerds
  3. thelostbaeddel reblogged this from fuckyeahfluiddynamics
  4. scorpshirl reblogged this from scinerds
  5. imperiatrix reblogged this from fuckyeahfluiddynamics
  6. jungle-juicy reblogged this from fuckyeahfluiddynamics
  7. guerrillalenguado reblogged this from memewhore and added:
    Rayleigh-Benard convection: If you make a proper cup of hot chocolate this holiday, watch carefully and you just may...
  8. mrdarkglasses reblogged this from thestreetballet
  9. dyingumbrella reblogged this from jacknotzak
  10. starsandspectra4ever reblogged this from scinerds
  11. jacknotzak reblogged this from fuckyeahfluiddynamics
  12. nanodash reblogged this from fuckyeahfluiddynamics
  13. midnighthalide reblogged this from fuckyeahfluiddynamics
  14. agentflamingotonguecowrie reblogged this from scinerds
  15. drwh091011 reblogged this from thecraftychemist
  16. hotdogcephalopod reblogged this from dissectionsbyhaven
  17. imogen-dragons reblogged this from thecraftychemist
  18. inattentivebobcat reblogged this from thecraftychemist
  19. renegade-centigrade reblogged this from fuckyeahfluiddynamics
  20. thesleepingramen reblogged this from thecraftychemist
  21. clinics-and-kettlebells reblogged this from somuchscience and added:
    Someone spent a minute and a half filming hot cocoa. I mean yes the science behind it is cool. But that’s a full 87...