Message 11005

TUFLOW FV
TUFLOW FV - STM
Available since version: 2026.2.0
ERROR 11005 - floating point error returned by bed mass update

Description

A NaN (not-a-number) value was detected in the bed elevation change after a bed mass update. This indicates a floating point failure in the sediment transport calculations.

Suggestions

Check the model for extreme or unrealistic sediment flux values. Review the output hydraulic model bed shear stress (TAUB) and sediment transport bed shear stresses (TAUC, TAUW and TAUCW if applicable). Review the specified sediment fraction models for high or unrealistic parameterisation for the sediment type. If the sediment fraction configuration appears reasonable, reducing the sediment transport timestep (using the sediment control file Update dt == command) may help resolve the issue.