Description
Return ideal signed capillary-rise head.
Infiltration and capillary models describe water movement under specific geometry and boundary assumptions. A square-root-time contribution, ponding boundary or ideal cylindrical-pore rise is a local model term; it does not fit soil parameters or establish a whole profile’s hydraulic behavior. Units of time and length must remain compatible throughout.
Return ideal signed capillary-rise head.
When to use this tool
Use Capillary Rise Pore Radius Factor when checking the stated limited infiltration or ideal capillary term.
How to use the tool and how it works
- Enter surfaceTension, contactAngleRadians, radius, liquidDensity, gravity. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read head. Use the output convention below.
Return ideal signed capillary-rise head. Require surfaceTension >= 0 and positive radius/liquidDensity/gravity; head = 2*tension*cos(contactAngleRadians)/(radius*density*gravity).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| surfaceTension | Surface Tension | Required. Finite number; minimum 0. |
| contactAngleRadians | Contact angle in radians; negative cosine yields a capillary depression. | Required. Finite number. |
| radius | Radius | Required. Finite number; strictly above 0. |
| liquidDensity | Liquid Density | Required. Finite number; strictly above 0. |
| gravity | Gravity | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| head | Ideal cylindrical-pore height; coherent SI inputs produce metres. | Required. Finite number. |
{
"input": {
"surfaceTension": 0.072,
"contactAngleRadians": 0,
"radius": 0.001,
"liquidDensity": 1000,
"gravity": 10
},
"output": {
"head": 0.0144
}
}Limitations and assumptions
- Angles above pi/2 can give depression; this ideal cylindrical-pore relation does not reconstruct soil pore networks or actual retention.
- 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 measured hydraulic properties and the appropriate complete infiltration/retention model, including boundary conditions and validity regime, for field predictions.
References
Similar or alternative tools
- Soil Matric Head Pressure Factor
Convert signed matric head to pressure.
- Soil Water Pore Share
Return water-filled pore share.