My thermal analysis using the THOPT,QUASI option worked fine in ANSYS 7.1,
but generates the error shown below in both ANSYS 8.0 and ANSYS 8.1. Why?
**Error in unsym ICCG zero row encountered
*** ERROR *** CP= 5.172 TIME= 11:42:17
Unsymmetric ICCG error, solution
Defect 25233 was filed and corrected in the UP20040716 build of ANSYS 9.0.
Essentially, the problem was due to some extraneous nodes existing in the
model. At 8.0, there were changes to the underlying data structures that feed
the solvers, and rather than giving the number of nodes that the solver actually
sees, it now gives the total number of nodes, so the solver thinks that there are
more rows in the matrix then there actually are; hence the message. The
workaround is to delete these extraneous nodes before solution.