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converting a general form of PDE to weak form PDE

Posted Aug 16, 2014, 8:46 a.m. EDT Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.3b 2 Replies

Saeed Mehrang
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Hi all ,

I am going to define a weak form of PDE on boundaries of a cylinder based on 4 dependent variables V_m, m, n , h. The following equations need to be converted to weak form but I do not know how to do it. unfortunately there is not any model example or explanation in this regard in comsol tutorial or model library.

equations:

1. d(V_m)/dt=G_Na*(V_m-E_Na)+G_K*(V_m-E_K)+G_l*(V_m-E_l)
2. dm/dt=a_m*(1-m)-b_m*m
3. dn/dt=a_n*(1-n)-b_n*n
4. dh/dt=a_h*(1-h)-b_h*h

could someone help me please??
thanks in advance
2 Replies Last Post Aug 16, 2014, 11:06 a.m. EDT
Pu Zhang
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Posted: 1 decade ago Aug 16, 2014, 10:58 a.m. EDT
Probably you'd go for technical support.
Probably you'd go for technical support.
Saeed Mehrang
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Posted: 1 decade ago Aug 16, 2014, 11:06 a.m. EDT
I just want to know how a pde should be entered as a weak expression. For example I know the weak form of Poisson's equation weak expression would be ux*test(ux)-uy*test(uy)+test(u). But I don't have any idea about those four equations that I mentioned above.
I just want to know how a pde should be entered as a weak expression. For example I know the weak form of Poisson's equation weak expression would be ux*test(ux)-uy*test(uy)+test(u). But I don't have any idea about those four equations that I mentioned above.

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