You can change the gravitational acceleration, g, since it is directly proportional to Gr. Use constant viscosity, density and thermal expansion coefficient.
Dear Halldor, thank you very much for you reply. what will be the temperature difference (del T )in that case ?..I think I need to keep the constant value of this too.. kindly advice.
Regards
Ravi
I can give you an example: Consider two plates, one at 20°C, other at 100°C with a distance 0.01 m. If the dynamic viscosity is 1e-5 (air) and expansion coefficient is 0.003, then Gr = g*1e-5*(100-20)*0.01^3 / (1e-5)^2. You would then adjust g to get the preferred Grashof number.
Dear Dr. Halldor, I got your point. Thank you very much for your advice. can the same be done for the solidification/melting problem. e.g. a cavity is filled with water and I need to investigate the solidification time of water for different Gr, can I adopt the same procedure which you just described ?
Regards
Ravi
Yes, I would do the same there, assuming that the phase change takes place at a fixed temperature. The only concern in this case is that the viscosity of water changes rapidly with temperature when you are near the melting temperature. But you would then use an average value for the viscosity.
Yes Dr., I do the same thing. I take the average value of viscosity. your words helped me a lot..thank you very much..May I keep in touch with you and write you further if I need any guidance from you...Thank you very much
Regards
Ravi
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