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Detail: Undefined value found in the stiffness matrix.

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my topic is to simulate the form and propagation of the streamer in transformer oil. AC/DC module to model the possion's equation and chemical Engineering module to model the drift-dominated charge-continuity equations are used in COMSOL. some question appear and note as follows.

"Detail: Undefined value found in the stiffness matrix.
There are 1037 equations giving NaN/Inf in the matrix rows for the variable mod1.T
at coordinates: (500000,0), (500000,470099), (500000,940198), (805152,792226), (1.1103e+006,644255), ...
There are 1037 equations giving NaN/Inf in the matrix rows for the variable mod1.c
at coordinates: (500000,0), (500000,470099), (500000,940198), (805152,792226), (1.1103e+006,644255), ...
There are 1037 equations giving NaN/Inf in the matrix rows for the variable mod1.c3
at coordinates: (500000,0), (500000,470099), (500000,940198), (805152,792226), (1.1103e+006,644255), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns"

I wonder what probably cause the problem. the file has been attach. thanks for your help. so many people expect solve the problem. thanks


0 Replies Last Post 23.07.2011, 05:12 GMT-4
COMSOL Moderator

Hello LV Shuming

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