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concentrated species transport with moving mesh

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Hi everyone,

I am dealing with a model of binary liquid to evaporate. I use the concentrated species transport to simulate the concentration field of two components in liquid as well as a moving mesh to track the free liquid surface which shrinks with the liquid evaporation. The evaporation rates of both components are variable. However, I have several troubles in establishing this model:

1. In concentrated species transport module it is available to set only one component flux at the boundary (here is the free liquid surface). Is there anyone kowning how I add the other component flux at the boundary?

2. I once used the surface reaction to treat both components evaporation as surface consumption rates. But I don't kown how to give the initial concentration (mol/m^2) at the surface. Because I am just able to figure out their volumetric concentration (mol/m^3). Does anyone have an idea to sovle the problem or is it reasonable to model in such way?

3.At last, is it compatible to couple moving mesh with concentrated species transport module? For moving mesh it makes use of down(rho), which is the mixed liquid's density, and up(rho) at the interface while in fact the evaporation mass is related to the pure components' density. Moreover, when the boundary moves, how does the concentrated species transport module identify the boundary concentration? Will it produce an error during computational process?

I am really puzzled by the series of problems and appreciated anyone who can illuminate me on them. Thanks a lot in advance.

Yuhong

2 Replies Last Post 2015年8月6日 GMT-4 02:00

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Posted: 9 years ago 2015年8月6日 GMT-4 01:47
I can reply to item 2:

1 mol/L corresponds to 1.184e-10 mol/cm². This is achieved considering that 1 mol is Avogadro's (N_A) number of species. Hence, at the surface resides (N_A)^(2/3) species. That devided by N_A gives the number of moles at the surface.

BR
Lasse
I can reply to item 2: 1 mol/L corresponds to 1.184e-10 mol/cm². This is achieved considering that 1 mol is Avogadro's (N_A) number of species. Hence, at the surface resides (N_A)^(2/3) species. That devided by N_A gives the number of moles at the surface. BR Lasse

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Posted: 9 years ago 2015年8月6日 GMT-4 02:00
Hence, concentration c converts to {(c*N_A)^(2/3)}/N_A = c^(2/3)*(N_A)^(-1/3).
Hence, concentration c converts to {(c*N_A)^(2/3)}/N_A = c^(2/3)*(N_A)^(-1/3).

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