Hi,
My problem It is about the diffusive transport equation designed for a two-dimensional plane. The physical problem consists in predicting the drying time according to the radial and tangential humidity of a 48 mm by 48 mm piece of radiata pine wood.
I need to use this equation.
I need to be able to get this same data:
The idea is to design a code in wolfram mathematica to obtain radial vs. CHO (Moisture Content) and tangential vs. CHO graphs. I've been using this code but I can't get the necessary results
Ec = D[CH[x, y, t], t] ==
Dm*(D[CH[x, y, t], x, x] + D[CH[x, y, t], y, y]);
Ecx = D[CH[x, y, t], t] == Dm*(D[CH[x, y, t], x, x]);
Ecy = D[CH[x, y, t], t] == Dm*(D[CH[x, y, t], y, y]);
M0 = 130;
a = -21.05;
b = 18.5;
Dm = Exp[a + (b*CH[x, y, t])];
ci = CH[x, y, 0] == M0;
ejes = 24;
R = {D[CH[x, y, t], x] == 0 /. x -> 0,
D[CH[x, y, t], y] == 0 /. y -> 0,
D[CH[x, y, t], x] == 0 /. x -> ejes,
D[CH[x, y, t], y] == 0 /. y -> ejes};
H = NDSolve[{Ec, ci, R}, CH, {t, 0, 40}, {x, 0, ejes}, {y, 0, ejes}];