A Warning message in AFT Impulse alerts users to issues in the model that will affect the model results. These warnings often offer important information about the converged solution or the model itself, and should always be reviewed before considering the results to be meaningful for the system.

WARNINGS

• Air Valve Junction X steady-state pressure Y is below cracking pressure Z

• Chempak temperature and/or pressure is out of range for the following

• FCV could not control flow at Junction X

• Flow may not be balanced at Junction X

• Flow is into system at Reservoir Junction X...

• HGL, EGL and head loss results may not be meaningful for variable density systems

• Junction X cavitates. Cavitation at air valve junctions can cause anomalous results which may be incorrect.

• Junction X Exceeded Runout Flow Rate...

• Junction X Has Insufficient Pump NPSH

• Maximum peak to peak pressure limit has been exceeded (PFA)

• Negative added pressure by pump at Junction X

• Pipe force calculations are not reliable when cavitation occurs during the simulation

• Pipe X completely drained at Y seconds. Predicted results are not reliable after this time.

• Pipe X - Station Y pressure is below 10% vapor pressure margin. Pressure = Z. Note: There are also A other locations (PFA Only)

• PRV could not control pressure at Junction X

• PSV could not control pressure at Junction X

• Pump X had efficiency greater than 100%

• Pump X is using a Standard Pump Curve and... (Family of warnings)

• Static pressure lower than vapor pressure at inlet/outlet of pipe/junction X

• Surge Tank junction X completely drained at Y seconds. Predicted results are not reliable after this time.

• Tank Junction X completely drained at Y seconds. Predicted results are not reliable after this time.

• Temperature at inlet of pipe X is above/below max/min fluid temperature range

• The following pipes have vapor volumes in computing stations greater than 10% but less than 100% of the liquid computing volume

• Transient data was extrapolated at Junction X

• Transient static pressure lower than vapor pressure at Pipe X Station Y

• Unique solution not possible - Relief valve cycles