The CFX Solver fails with an error similar to the following, if Efficiency Output is enabled for a calculation involving a fluid defined as a Fixed Composition Mixture:
Error in subroutine FNDVAR :
Error finding variable MASFRC_MT1_FL1
GETVAR originally called by subroutine CAL_ENTH_ISEN
No error is generated for Pure Substances or Variable Composition Mixtures.
This is due to a coding error in the CFX Solver.
Redefine your working fluid as a Pure Substance with the same effective properties as the mixture, if possible.
ANSYS CFX Release 12.0. A custom executable for ANSYS CFX 11.0 SP1 is available on request.