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Torsten
Posts:
1,717
Registered:
11/8/10


Re: PDE  spherical coordinates question (polar)
Posted:
Aug 21, 2013 2:46 AM


"Saad" wrote in message <kuvtva$guv$1@newscl01ah.mathworks.com>... > Hi, > I'm trying to solve the following PDE using (pdepe). > Does anyone have any tips on how to input the variable coefficients for this equation. > > dH/dt + 1/sinx d/dx(H^3 (sinx)^2)=0 > > > Thanks, > Saad
pdepe is suited for PDEs which contain a secondorder spatial derivative (in your case, this would be an expression involving d^2H/dx^2). Since your equation is a firstorder PDE, you will have to solve it using a different tool. Differentiating out, you get dH/dt + 3*H^2*sin(x)*dH/dx = 2*H^3*cos(x).
Best wishes Torsten.



