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Problem in Global Equations defined variable
Posted 2014年4月7日 GMT-4 19:43 Structural Mechanics 2 Replies
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Hi all,
Does anybody know how to fix this? I am simulating a cavity filled with incompressible fluid under external pressure. Following the COMSOL Blog: www.comsol.com/blogs/computing-controlling-volume-cavity/, I used the global equations to define a pressure load "Inner_pressure" to the inner wall of a cavity beam. The global equation is set to find out whatever value of "Inner_pressure" only if it can satisfy the constraint that the cavity's volume is always the same to undeformed state. I tried this method in 2D successfully, but in 3D it has a error like this.
****************************************
Failed to find a solution.
Singular matrix.
There are 1 void equations (empty rows in matrix) for the variable comp1.Inner_pressure.
at coordinates: (0,0,0), ...
Returned solution is not converged.
****************************************
Does anybody know how to fix this? I am simulating a cavity filled with incompressible fluid under external pressure. Following the COMSOL Blog: www.comsol.com/blogs/computing-controlling-volume-cavity/, I used the global equations to define a pressure load "Inner_pressure" to the inner wall of a cavity beam. The global equation is set to find out whatever value of "Inner_pressure" only if it can satisfy the constraint that the cavity's volume is always the same to undeformed state. I tried this method in 2D successfully, but in 3D it has a error like this.
****************************************
Failed to find a solution.
Singular matrix.
There are 1 void equations (empty rows in matrix) for the variable comp1.Inner_pressure.
at coordinates: (0,0,0), ...
Returned solution is not converged.
****************************************
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2 Replies Last Post 2017年6月27日 GMT-4 14:46