Fluid deceleration is outside the valid range

A Transient Solver Error in AFT Impulse

Full Message is:

Error occurred while running Transient Solver. Fluid deceleration is outside the valid range for the check valve type selected

This transient solver error message can occur if the model has a check valve defined using the Estimate from Fluid Deceleration valve model. The error message indicates that the fluid deceleration calculated for the check valve exceeds the maximum deceleration for the current valve type. If the deceleration exceeds the known deceleration vs maximum reverse velocity data the reverse velocity to close the check valve can't be calculated and the transient calculations can't proceed. See the Check Valve topic for more information on how the Estimate from Fluid Deceleration option is modeled.

The user will need to consider using the User Specified option to directly define the reverse velocity to close for the check valve, or should consider using a different check valve type if appropriate for the system.