Description
Multiply nonnegative discharge by interval for volume and multiply that by time for firstMoment.
Flow calculations relate volume, time, cross-section, velocity, and supplied model parameters. A local ratio or contribution does not by itself solve a complete hydraulic system.
Multiply nonnegative discharge by interval for volume and multiply that by time for firstMoment.
When to use this tool
Use Hydrograph Time Centroid Term when you need one explicit flow component with coherent units and references.
How to use the tool and how it works
- Enter time, discharge, interval. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read volume, firstMoment. Use the output convention below.
Multiply nonnegative discharge by interval for volume and multiply that by time for firstMoment.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| time | Time | Required. Finite number. |
| discharge | Discharge | Required. Finite number; minimum 0. |
| interval | Interval | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| volume | Volume | Required. Finite number. |
| firstMoment | First Moment | Required. Finite number. |
{
"input": {
"time": 4,
"discharge": 3,
"interval": 2
},
"output": {
"volume": 6,
"firstMoment": 24
}
}Limitations and assumptions
- Discharge and interval use coherent units and time uses a common origin; a centroid requires summing all moments and dividing by total volume, which is not done here.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use surveyed geometry, appropriate calibration, and a complete hydraulic model for operational or design decisions.
References
Similar or alternative tools
- Hydrograph Segment Volume Trapezoid
Average startFlowM3PerSecond and endFlowM3PerSecond and multiply by nonnegative durationSeconds for volumeM3.
- Hydrograph Step Average Instantaneous Reference
Multiply the selected left or right endpoint flow by nonnegative intervalSeconds for stepVolume.