The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » Software » comp.soft-sys.matlab

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: PDE - spherical coordinates question (polar)
Replies: 2   Last Post: Aug 21, 2013 1:14 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]

Posts: 1,717
Registered: 11/8/10
Re: PDE - spherical coordinates question (polar)
Posted: Aug 21, 2013 2:46 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"Saad" wrote in message <kuvtva$guv$>...
> 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 second-order spatial derivative (in your case, this would be an expression involving d^2H/dx^2).
Since your equation is a first-order 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

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.