A Caution message in AFT xStream

Full Message text is:

The maximum transient pipe Mach Number X was significantly lower than the estimate Y. Lowering the estimated maximum pipe Mach number may increase accuracy. The estimate must be set above the simulation maximum pipe Mach Number, a value of at least Z is recommended

 

This is a cautionary notice that the maximum transient Mach number in the pipes remained significantly below the Estimated Maximum Pipe Mach Number During Transient, which is defined in the Sectioning panel. Decreasing the estimated maximum Mach number may increase the accuracy and improve the run time. Note that if the estimated maximum Mach number is less than the maximum Mach number encountered during the simulation, the solution will become unstable, so the estimated maximum Mach number should not be defined to be less than the recommended value given in the caution.