Problems with NDSolve
- To: mathgroup at smc.vnet.net
- Subject: [mg5991] Problems with NDSolve
- From: lichtner at swri.edu
- Date: Sat, 8 Feb 1997 22:38:09 -0500
- Organization: Southwest Research Institute
- Sender: owner-wri-mathgroup at wolfram.com
I'm having problems with using NDSolve to solve partial differential
equations. Has anyone had any luck with with??
I tried a very simple heat conduction equation as a test with constant
initial temperature and constant temperature at the left face, and a zero
flux boundary condition at the right face:
soln =NDSolve[{D[y[x,t], t] == D[y[x,t], x, x],
y[0,t]==1, y[x,0]==0,
Derivative[1,0][y][5,t]==0},
y[x,t], {x,0,5}, {t,0,10}]
I get a strange warning message:
NDSolve::"ibcinc":
"Warning: Boundary and initial conditions are inconsistent."
And after plotting the results with
Plot3D[Evaluate[y[x,t] /. First[soln]],
{x,0,5}, {t,0,10},PlotPoints->30]
get just a flat surface with nothing happening!
Thanks for any help.
...Peter
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Peter C. Lichtner <lichtner at swri.edu>
Southwest Research Institute http://www.swri.edu/
Center for Nuclear Waste Regulatory Analyses (CNWRA)
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