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ISSN Online: 2377-424X

International Heat Transfer Conference 12
August, 18-23, 2002, Grenoble, France

Onset of thermal convection in a horizontal fluid layer under ramp heating

Get access (open in a dialog) DOI: 10.1615/IHTC12.40
6 pages

Resumo

The onset of convective motion in an initially quiescent, horizontal fluid layer heated from below is analyzed by using propagation theory. In the present system the bottom surface temperature is changed suddenly from a constant to a linear ramp with time. With rapid heating cellular convection will set in due to buoyancy forces at a certain time. For rigid-rigid boundaries predictions of the onset time of convective motion are compared with available experimental data. It is very interesting that propagation theory recovers the well-known critical values of Rac = 1708 and ac = 3.12 for large time and for water manifest convection is detected around four times the predicted critical time.