Re: Re: PDE
- To: mathgroup at smc.vnet.net
- Subject: [mg42932] Re: [mg42917] Re: [mg42801] PDE
- From: "Teodor Stanescu" <teodoor at hotmail.com>
- Date: Mon, 4 Aug 2003 00:46:00 -0400 (EDT)
- References: <200308020812.EAA22060@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi all,
Could anyone help me with the following problem?
\!\(\(eques = {\[IndentingNewLine]\[PartialD]\_t Ef[t, x] + \[PartialD]\_x
Ef[
t, x] == \(-el\)*
Ef[t, x]*\((mun*n[t, x] + mup*p[t, x])\)/\((eps0*
eps)\)\[IndentingNewLine] +
el*\((m2[t, x] - m1[t, x] + p[t, x] - n[t, x])\)/\((eps0*
eps)\), \ \[IndentingNewLine]\[PartialD]\_t m1[t, x] ==
g1n*n[t, x]*\((M0 - m1[t, x])\) -
g2p*p[t, x]*m1[t, x], \ \[IndentingNewLine]\[PartialD]\_t m2[t,
x] == g1p*p[t, x]*\((M0 - m2[t, x])\) -
g2n*n[t, x]*m2[t, x], \ \[IndentingNewLine]\[PartialD]\_t n[t,
x] == k0*Exp[\(-miu\)*x] +
mun*n[t, x]*\[PartialD]\_x Ef[t, x] -
g1n*n[t, x]*\((M0 - m1[t, x])\) -
g2n*n[t, x]*m2[t, x], \ \[IndentingNewLine]\[PartialD]\_t p[t,
x] == k0*Exp[\(-miu\)*x] -
mup*p[t, x]*\[PartialD]\_x Ef[t, x] -
g1p*p[t, x]*\((M0 - m2[t, x])\) -
g2p*p[t, x]*m1[t, x]\[IndentingNewLine]};\)\)
bcond = {
Ef[0, x] == 800/0.02,
m1[0, x] == 0, m1[t, 0] == 0, m1[t, l] == 0,
m2[0, x] == 0, m2[t, 0] == 0, m2[t, l] == 0,
n[0, x] == k0*Exp[-miu*x],
p[0, x] == k0*Exp[-miu*x]
};
Timing[S =
Ef /. First[
NDSolve[{eques, bcond}, {Ef, m1, m2, n, p}, {t, 0, 1}, {x, 0, l},
PrecisionGoal -> 1]]]
Plot3D[S[t, x], {t, 0, 1}, {x, 0, 1}, PlotRange -> All, PlotPoints -> 25];
All the other coefficients are constants:
\!\(\(g1n = 10\^\(-10\);\)\)
\!\(\(g1p = 10\^\(-8\);\)\)
\!\(\(g2n = 10\^\(-9\);\)\)
\!\(\(g2p = 10\^\(-7\);\)\)
\!\(\(k0 = 0.783*10\^13*45*4*10\^\(-4\)*15/60;\)\)
\!\(\(el = 1.6022*10\^\(-19\);\)\)
\!\(\(eps0 = 8.8542*10\^\(-16\);\)\)
eps = 6.3;
\!\(\(mun = 2.8*10\^\(-3\);\)\)
mup = 0.15;
\!\(\(M0 = 10\^13;\)\)
l = 0.0239;
miu = 1.7165/l;
After running the above code I got the following error:
NDSolve::nderr: Error test failure at t == 0.0023669463792995483`; unable to
\
continue.
Any help will be appreciated.
Thank you.
Teo.
- References:
- Re: PDE
- From: sean kim <shawn_s_kim@yahoo.com>
- Re: PDE