Plumbing Weir Flow Triangular Calculator
Free-discharge sharpVnotch Q=(8/15) Cd√2g tan(θ/2) h^2.5, no submerged flow/surface tension correction; actual independently calibratedCdand0<θ<π. Actual independently matched units, regime, material/equipment and governing references; not a hydraulic code, safe pressure, water pot ability or operational approval.
Description
A sharp triangular weir relates free-discharge flow to head and notch angle.
A sharp triangular weir relates free-discharge flow to head and notch angle.1
The coefficient and ideal free-flow assumptions must match the installation. The calculation and input requirements are explained below.
When to use Plumbing Weir Flow Triangular Calculator
Enter positive independently calibrated coefficient and gravity in m/s², notch angle strictly between 0 and pi radians, and nonnegative head in meters.
How to use Plumbing Weir Flow Triangular Calculator and how it works
- Prepare the measurements or independently established model inputs described below, with matching units and observation scope.
- Enter the required fields and run Plumbing Weir Flow Triangular Calculator.
- Read the result fields using the formula, output units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerCalibratedTriangularWeirDischargeCoefficient | Caller Calibrated Triangular Weir Discharge Coefficient. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| callerGravityMetersPerSecondSquared | Caller Gravity Meters Per Second Squared. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualNotchAngleRadians | Actual Notch Angle Radians. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualHeadAboveNotchMeters | Actual Head Above Notch Meters. Use the units and matching context stated in the calculation below. | number | Required; nonnegative; finite; other constraints below |
Enter positive independently calibrated coefficient and gravity in m/s², notch angle strictly between 0 and pi radians, and nonnegative head in meters. Apply the free sharp V-notch equation and return m³/s. Submergence and surface-tension corrections are excluded.
Q=(8/15)*Cd*sqrt(2*g)*tan(angleRadians/2)*headM^2.5 Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Numeric result under the formula and output units explained above. | number |
{
"input": {
"callerCalibratedTriangularWeirDischargeCoefficient": 1,
"callerGravityMetersPerSecondSquared": 2,
"actualNotchAngleRadians": 1.5707963267948966,
"actualHeadAboveNotchMeters": 1
},
"output": {
"result": {
"value": 1.0666666666666664
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Plumbing Detention Basin Weir Length Calculator for a complementary operation: A free rectangular weir relates flow to crest length and head.
Use Plumbing Detention Basin Outlet Orifice Size Calculator for a complementary operation: An ideal outlet orifice relates discharge to area, head and coefficient.
References
-
Plumbing Weir Flow Triangular Calculator — tool.io
Similar or alternative tools
- Plumbing Detention Basin Weir Length Calculator
A free rectangular weir relates flow to crest length and head.
- Plumbing Detention Basin Outlet Orifice Size Calculator
An ideal outlet orifice relates discharge to area, head and coefficient.