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why are my solutions the same as initial values?
Posted 18 mars 2013, 04:39 UTC−4 Studies & Solvers Version 4.3a 1 Reply
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Hi. I build a 1D time-dependent model (transport of diluted species).
using conservative form.
convection transport mechanism
D=0;
u=-k/x^m; (k is a constant)
R=0;
no flux
iniitlal distribution: 1/(x^4*sqrt(2*pi)*log(sigma))*exp(-0.5*((log(x)-log(r_m))/(log(sigma)))^2)
k=4.92*10^(-14)/3600
m=3
sigma=1.2
r_m=0.034
But when I solve it, the solutions at all time are the same as initial values.
I also solve this problem with matlab, the solutions should be in the same shape but different values.
I don't know what had happened. The mph file is too big to be uploaded.
Would you please help me? Thanks very much.
using conservative form.
convection transport mechanism
D=0;
u=-k/x^m; (k is a constant)
R=0;
no flux
iniitlal distribution: 1/(x^4*sqrt(2*pi)*log(sigma))*exp(-0.5*((log(x)-log(r_m))/(log(sigma)))^2)
k=4.92*10^(-14)/3600
m=3
sigma=1.2
r_m=0.034
But when I solve it, the solutions at all time are the same as initial values.
I also solve this problem with matlab, the solutions should be in the same shape but different values.
I don't know what had happened. The mph file is too big to be uploaded.
Would you please help me? Thanks very much.
1 Reply Last Post 18 mars 2013, 05:35 UTC−4
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Posted:
1 decade ago
By the way, unit for all the parameters are as follows:
m [1]
k [um^4/h]
r [um]
m [1]
k [um^4/h]
r [um]