Executing the program below I get the
... is not a polynomial
error message. I don't have an idea why I am getting this -- any suggestions?
ClearAll["Global`*"]
Needs["NDSolve`FEM`"]
Q = 60;
A = 4000;
nb = 0.42;
dens = 1.48;
Co = 0.05;
Vx = Q/A;
Dx = 73.51*Vx + 0.282;
R = 1 + (dens/nb)*(0.9292/(1 + 0.092*Ccu[x, t])^2);
reator = Dx*D[Ccu[x, t], x, x] - Vx*D[Ccu[x, t], x] -
R*D[Ccu[x, t], t];
initial = Ccu[x, 0] == 0;
b1 = {Ccu[0, t] == Co, Ccu[300000, t] == 0};
regiao = ImplicitRegion[True, {{x, 0, 500000}}];
solucao =
NDSolve[{reator == 0, initial,
DirichletCondition[Ccu[x, t] == Co, x == 0],
DirichletCondition[Ccu[x, t] == 0, x == 100000]},
Ccu, {t, 0, 100000}, {x} ∈ regiao]
CoefficientArrays::poly: -(1+3.27432/(1+0.092 Ccu)^2) Ccu\$11498-(3 Ccu\$11499)/200 + 1.38465 Ccu\$11500 is not a polynomial. >>
NDSolve::femper: PDE parsing error of {-(1+3.27432/(1+0.092 Ccu)^2) Ccu\$11498-(3 Ccu\$11499)/200+1.38465 Ccu\$11500}. Inconsistent equation dimensions. >>