Number of degrees of freedom in LHS and RHS aren't equal

Issue:

I ran an analysis, and this error came up: "Error in solving the linear system of equations. Number of degrees of freedom in LHS and RHS aren't equal"

Applies to:

  • Simulation
  • Topology Optimization

Cause:

The cause for this issue is typically due to an error in a boundary condition or a constraint block.

Solution:

    • Adjust the the tolerances for each boundary condition and ensure they all make sense and work? 
      • The nodes might be part of dependent nodes of a Tie Constraint (that theoretically will have to follow the independent nodes),
    • Make sure the constraint and restraint blocks are used correctly in Topology Optimizations
      • Ensure that there are no same nodes in a Displacement Restraint (that theoretically will be fixed (if the value is 0) or have a Prescribed Displacement (if the value is non-zero))

More on this topic:

Keywords:

 error analysis simulation system topology of linear issue degrees freedom aren't equal lhs rhs 
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