Coupled non linear first order equation [message #92867] |
Tue, 15 March 2016 15:07  |
say_cheese74
Messages: 1 Registered: March 2016
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Junior Member |
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I have a system of (momentum) equations in cylindrical coordinates:
(r,theta,phi)
rho*(dv/dt+(v.del)v=A(r,theta,phi)
where the velocity v(r,theta,phi) and A are vectors and dv/dt is the partial derivative wrt time. del is the gradient.
I am trying to find the steady state solution to the equation
(v.del)v=A.
I have tried different simple methods but nothing converges. Any suggestions .
Thanks
Jay
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Re: Coupled non linear first order equation [message #92873 is a reply to message #92867] |
Wed, 16 March 2016 10:24  |
Craig Markwardt
Messages: 1869 Registered: November 1996
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Senior Member |
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On Tuesday, March 15, 2016 at 6:07:03 PM UTC-4, say_cheese74 wrote:
> I have a system of (momentum) equations in cylindrical coordinates:
> (r,theta,phi)
>
> rho*(dv/dt+(v.del)v=A(r,theta,phi)
> where the velocity v(r,theta,phi) and A are vectors and dv/dt is the partial derivative wrt time. del is the gradient.
>
> I am trying to find the steady state solution to the equation
> (v.del)v=A.
Obvious question: did you try Runge Kutta (IDL's RK4?).
Craig
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