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Two phase flow in column, apply gas pressure on the bottom boundary

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Dear all,

I want to use the "two phase flow in column" in the application libraries to develop my own two phase flow model. In the template, the gas cannot flow through the bottom boundary, but in my model, the gas is allowed to flow through the bottom. When I applied the gas pressure on the bottom boundary, there always appears errors, like

Repeated error test failures. May have reached a singularity.
Time : 76399.46224196325
Attempt to evaluate negative power of zero.
Function: ^
Failed to evaluate temporary symbolic derivative variable.
Variable: comp1.kr wVDN$comp1.p nw, Defined as: (((2*(1-((1-(comp1.Se w^(1/comp1.M)))^comp1.M)))*(-((((1-(comp1.Se w^(1/comp1.M)))^(comp1.M-1))*comp1.M)*(-(((comp1.Se w^((1/comp1.M)-1))*(1/comp1.M))*((((1+(((comp1.alpha*comp1.rm1(comp1.Hc/unit m cf))*unit m cf)^comp1.N))^((-comp1.M)-1))*(-comp1.M))*(((((comp1.alpha*comp1.rm1(comp1.Hc/unit m
Failed to evaluate temporary symbolic derivative variable.

I tried many times, and thought the problem should be on the van Gentuchen model due to the boundary condtion. If you have any experience to set boundary condition for two phase flow, could you please share it with me? Thank you so much for your help.

Regards,

Yu



0 Replies Last Post 01.03.2017, 23:51 GMT-5
COMSOL Moderator

Hello Yu Zhang

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