Plumbing Hazen Williams Head Loss Calculator
Metric empiricalHazen–Williams head loss10.67LQ^1.852/(C^1.852d^4.8704), water regime/coefficients independently verified; no Darcy friction factor or minor loss. Actual independently matched units, regime, material/equipment and governing references; not a hydraulic code, safe pressure, water pot ability or operational approval.
Description
Hazen–Williams head loss uses an empirical water-flow relationship.
Hazen–Williams head loss uses an empirical water-flow relationship.1
Pipe size, flow units and the selected coefficient are essential to applying its metric convention. The calculation and input requirements are explained below.
When to use Plumbing Hazen Williams Head Loss Calculator
Enter nonnegative pipe length meters and flow m³/s, positive matched C and bore meters.
How to use Plumbing Hazen Williams Head Loss 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 Hazen Williams Head Loss 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 |
|---|---|---|---|
| actualPipeLengthMeters | Actual Pipe Length Meters. Use the units and matching context stated in the calculation below. | number | Required; nonnegative; finite; other constraints below |
| actualVolumeFlowCubicMetersPerSecond | Actual Volume Flow Cubic Meters Per Second. Use the units and matching context stated in the calculation below. | number | Required; nonnegative; finite; other constraints below |
| callerMatchedHazenWilliamsC | Caller Matched Hazen Williams C. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualInnerDiameterMeters | Actual Inner Diameter Meters. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
Enter nonnegative pipe length meters and flow m³/s, positive matched C and bore meters. Apply the metric Hazen–Williams convention to return head loss meters. Minor losses and a Darcy friction factor are not calculated.
headLossM=10.67*lengthM*flowM3ps^1.852/(C^1.852*diameterM^4.8704) 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": {
"actualPipeLengthMeters": 1,
"actualVolumeFlowCubicMetersPerSecond": 1,
"callerMatchedHazenWilliamsC": 1,
"actualInnerDiameterMeters": 1
},
"output": {
"result": {
"value": 10.67
}
}
}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.
EPA documents Hazen–Williams and Darcy–Weisbach as alternative friction-headloss methods within network analysis. This tool evaluates one supplied pipe relationship and does not solve an entire hydraulic network.2
Alternative or Complementary methods
Use Plumbing Hazen Williams Velocity Calculator for a complementary operation: Hazen–Williams velocity is an empirical relationship between hydraulic radius and friction gradient.
Use Plumbing Friction Factor Laminar Calculator for a complementary operation: The laminar Darcy friction factor uses Reynolds number under a fully developed circular-pipe convention.
References
-
US EPA: EPANET — US Environmental Protection Agency
Similar or alternative tools
- Plumbing Hazen Williams Velocity Calculator
Hazen–Williams velocity is an empirical relationship between hydraulic radius and friction gradient.
- Plumbing Friction Factor Laminar Calculator
The laminar Darcy friction factor uses Reynolds number under a fully developed circular-pipe convention.