Broad-Crested Weir Flow Calculator
Ideal free-flow broad-crested critical control Q=Cd b√g(2H/3)^1.5, head includes caller approach convention. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
A broad-crested weir model relates head and crest width to free-flow discharge.
A broad-crested weir model relates head and crest width to free-flow discharge.1
Its coefficient and hydraulic applicability require independent establishment. Use this tool to calculate broad-Crested Weir Flow from the supplied measurements and assumptions.
When to use Broad-Crested Weir Flow Calculator
Use this tool to calculate broad-Crested Weir Flow from the supplied measurements and assumptions. Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
How to use Broad-Crested Weir Flow Calculator and understand its results
- Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
- Enter crestWidthM, upstreamHeadM, gravityMSecond2, callerDischargeCoefficient, using the field meanings and rules below, then run the tool.
- Read broadCrestedDischargeM3Second. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| crestWidthM | Crest width m | number | Required |
| upstreamHeadM | Upstream head m | number | Required |
| gravityMSecond2 | Gravity m second2 | number | Required |
| callerDischargeCoefficient | Caller discharge coefficient | number | Required |
Enter positive crest width in m, gravity in m/s² and discharge coefficient, with nonnegative head in m. Compute free-flow discharge in m³/s using the committed broad-crest expression. Coefficient is not constrained to≤1; submerged flow and coefficient calibration are not modeled.
Qm³/s=Cd×widthM×sqrt(g)×(2×headM/3)^(3/2) Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| broadCrestedDischargeM3Second | Broad Crested Discharge M3 Second; follow the units, sign, ordering and evidence convention stated above | number |
{
"input": {
"crestWidthM": 2,
"upstreamHeadM": 3,
"gravityMSecond2": 9,
"callerDischargeCoefficient": 1
},
"output": {
"broadCrestedDischargeM3Second": 16.970562748477143
}
}Limitations and assumptions
Its coefficient and hydraulic applicability require independent establishment. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Seepage Flow Net Calculator for this related task: A flow-net seepage estimate uses the ratio of independently counted channels and potential drops.
Use SCS Curve Number Runoff Calculator when its separate inputs and assumptions fit the question: The SCS curve-number runoff model relates precipitation to potential retention and initial abstraction.
References
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Broad-Crested Weir Flow Calculator — tool.io
Similar or alternative tools
- Seepage Flow Net Calculator
A flow-net seepage estimate uses the ratio of independently counted channels and potential drops.
- SCS Curve Number Runoff Calculator
The SCS curve-number runoff model relates precipitation to potential retention and initial abstraction.