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shallow water problem in PDE mode
Posted May 24, 2011, 9:45 a.m. EDT Studies & Solvers 0 Replies
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Hello, everyone. Could anyone give me some advice to solve the problem in the PDE mode
The equation is 1D shallow water?There are an example in Help file? but the initial water depth is nonzero in the example?as follows?
dz /dt+d(z*v)/dx=0
d(z*v)/dt + d(z*v*v)/dx + g*z*dz/dt - g*z*SF-E*d^2(z*v)/dx^2=0
The computation is OK when initial water depth z > 0 in the whole domain. However? when there exists z =0 in some place? I use two ways to try to solve the problem ?But it doesn't work
?1? the variable is chosen as Z and ZV
In this situation? the z*v*v in the second equation must be expressed as ZV*ZV/Z. The error is that there are NaN/INF in the matrix?
?2? the variable is chosen as Z and V
In this case? d(z*v)/dt must be expressed as z*dv/dt + v*dz/dt. The error is" There are 80 void equations (empty rows in matrix) for the variable V at coordinates: (75), (-53.5714), (,-32.1429), (-10.7143), (10.7143), ...
I am looking for reply from all of you
Thank a lot
Hello chaojun ouyang
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