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neoaspilet11
Joined: 29 Sep 2005
Posts: 276
Helped: 21
Location: Cebu, Philippines
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 30 Jan 2006 1:17 Partial Differential Equation |
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Hello every body,
Please help.
Derive the partial differential equation satisfied by the concentration u of a liquid diffusing through a porous solid. Hint: The rate at which liquid diffuses through an area is proportional to the area and to the concentration gradient in the direction perpindicular to the area.
Thanks in advance
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30 Jan 2006 1:17 Ads |
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steve10
Joined: 26 Mar 2002
Posts: 177
Helped: 33
Location: Los Angeles (Chinese)
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30 Jan 2006 7:05 Re: Partial Differential Equation |
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This is a standard derivation of heat or diffusion equation. Notice that, according to your statement, the rate deltaQ is proportional to du/dn,
deltaQ=-kdu/dn*dS*dt
where the minus sign means that the liquid flows in the opposite direction of the gradient. Based on this, you can mimic any derivation of the heat equation and end up with a heat equation.
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papu
Joined: 15 Feb 2006
Posts: 34
Helped: 2
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18 Feb 2006 9:26 Partial Differential Equation |
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| i dont understand ur question ....plzz write ur question is simple way??
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alizadeh_m
Joined: 29 Oct 2005
Posts: 27
Helped: 1
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21 Feb 2006 10:57 Re: Partial Differential Equation |
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| There is a wondeful software to solve such equations. it is FLUENT.
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maple
Joined: 27 Sep 2003
Posts: 106
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21 Feb 2006 11:02 Re: Partial Differential Equation |
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| I recommand the FEMLAB.
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needlove
Joined: 24 Jan 2006
Posts: 12
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24 Feb 2006 16:42 Partial Differential Equation |
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I recommand the MATHLAB
It's powerful
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