{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://www.calculatorx.com/schemas/physics.fluid.colebrook/1.0.0/input.json",
  "title": "Colebrook Friction Factor — input",
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "Re": {
      "type": "number",
      "minimum": 4000,
      "description": "Reynolds number. Turbulent-pipe correlation; Re < 4000 is rejected."
    },
    "rel_roughness": {
      "type": "number",
      "minimum": 0,
      "maximum": 0.05,
      "description": "Relative roughness ε/D. Alternative: eps_m and D_m together."
    },
    "eps_m": {
      "type": "number",
      "minimum": 0,
      "description": "Absolute roughness ε in metres. Requires D_m. Do not send with rel_roughness."
    },
    "D_m": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Pipe diameter in metres. Requires eps_m. Do not send with rel_roughness."
    }
  },
  "required": [
    "Re"
  ],
  "description": "Colebrook–White Darcy friction factor f from Re and ε/D. Turbulent pipes Re≥4000. Not laminar 64/Re. (calculation_version 1.0.0)"
}