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Calculate Potential Q

Description​

Calculates potential discharge Q at each stage in the cross-section characteristics table based on cross-section's slope (S0) and Manning;s N (ManningN) using normal depth calculations and Manning's equation for calculating velocity based on cross-section properties. Results are stored in the "Q" field in the input cross-section characteristics table (will be created by the tool). Input cross-section feature class must have these fields populated:

  • HydroID - unique cross-section identifier.
  • S0 - longitudinal slope at the cross-section (dimensionless).
  • ManningN - average roughness coefficient for cross-section.

Corresponding cross-section characteristics table must have these fields populated:

  • XID - HydroID of the source cross-section.
  • Z - absolute elevation.
  • H - depth.
  • A - area.
  • P - wetted perimeter.
  • R - hydraulic radius.
  • B - cross-section width.
  • XS - station of the first cross-section point at the Z-line.

Field Q will be created if it does not exist (otherwise it will be overwritten).

Usage​

ComputePFTableQ XLines PFTable

Parameters​

Parameter NameTypeDirectionData TypeDialog Reference
Input 3D Cross-section FCRequiredInputFeature Layer3D polyline feature class representing cross-sections (profile line). Feature class must have HydroID, S0, and ManningN fields populated.
Input Cross-section Characteristics TableRequiredInputTable ViewInput and output cross-section characteristic table with following attributes (many records for each cross-section):
  • XID (input) - HydroID of the source cross-section.
  • Z (input) - absolute elevation.
  • H (input) - depth.
  • A (input) - area.
  • P (input) - wetted perimeter.
  • R (input) - hydraulic radius.
  • B (input) - cross-section width.
  • XS (input) - station of the first cross-section point at the Z-line.
  • Q (output) - potential discharge for each Z.