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Saad
Posts:
3
Registered:
8/20/13


Re: PDE  spherical coordinates question (polar)
Posted:
Aug 21, 2013 1:14 PM


"Torsten" wrote in message <kv1nnj$nj4$1@newscl01ah.mathworks.com>... > "Saad" wrote in message <kuvtva$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.
Thanks Torsten  I'm trying to figure out an alternative method.
S



