Hot Plate, Frying Pan, Silicon Oil with Powdered Aluminum
Rayleigh-Bernard Cell
Rayleigh-Bernard Cell
lava lamps
lava lamp

 

Code Number: 4B20.50

Demo Title: Convection Cells or Rayleigh-Bernard Cell

Condition: Good

Principle: Solar Convection Cells

Area of Study: Thermodynamics, Astronomy

Equipment: 

Hot Plate, Frying Pan, Silicon Oil with Powdered Aluminum, Funnel.

Procedure:

See 2B40.55 in Thermodynamics, 2B40.55 in Astronomy, and 8B10.40 in Astronomy.

Place the frying pan on the hot plate.  Turn the hot plate to between 350 and 400 on the temperature dial.  Add the full pint of oil/aluminum powder mixture.

CAUTION: The oil does not have to be very hot to give good convection cells.  If the temperature is too high the oil may ignite.

Once the cells have formed they will appear very stable.  You can use a spoon to disturb the cell structure and watch its reformation.

This demo will show mostly 5 fold symmetry.

References:

  • Jay Pasachoff, "This Month's Cover...", TPT, Vol. 55, #3, Mar. 2017, p. 129.
  • Stephen J. Van Hook and Michael F. Schatz, "Simple Demonstrations of Pattern Formation", TPT, Vol. 35, #7, Oct. 1997, p. 391.
  • Cover Picture, TPT, Vol. 35, #7, Oct. 1997.
  • John Wettlaufer, "The Universe in a Cup of Coffee", Physics Today, Vol. 64, #5, May 2011, p. 66.
  • A. V. Getling, O. Brausch, "Cellular Flow Patterns and their Evolutionary Scenarios in Three-Dimensional Rayleigh-Bernard Convection", The American Physical Society, Physical Review E 67, 046313-1, 2003.
  • Jearl Walker, "2.90, Patterns in Hot Coffee and Other Fluids", The Flying Circus of Physics Ed. 2, p. 120.
  • Jearl Walker, "2.89, Tia Maria Worm-Like Patterns", The Flying Circus of Physics Ed. 2, p. 120.
  • Peacock, Rayleigh-Bernard Cells, E-mail, 2005.