{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://www.calculatorx.com/schemas/physics.fluid.hydraulic_diameter.input.json",
  "title": "Hydraulic diameter — input",
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "mode": {
      "type": "string",
      "enum": [
        "general",
        "circular",
        "rectangular",
        "annular"
      ],
      "description": "general (default, A and Pw), circular full pipe, closed rectangular duct, or annulus. Not Q=Av, Manning, Reynolds, Darcy, weir, orifice, pump, or NPSH."
    },
    "A": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Flow area in m². General mode, with Pw or Dh."
    },
    "Pw": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Wetted perimeter in m. Alias P. General mode."
    },
    "R": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Hydraulic radius A/P_w in m. Alternative to A+Pw. D_h=4R. Not a Manning n solve."
    },
    "Dh": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Hydraulic diameter in m. Inverts Pw or A in general mode."
    },
    "D": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Inside diameter in m. Circular full-pipe mode. D_h=D."
    },
    "a": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Internal width in m. Closed rectangular duct."
    },
    "b": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Internal height in m. Closed rectangular duct."
    },
    "D_o": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Annulus outer diameter in m."
    },
    "D_i": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Annulus inner diameter in m. Must be smaller than D_o."
    }
  },
  "description": "Hydraulic diameter D_h=4A/P_w. Full circular pipe D_h=D, closed rectangular duct 2ab/(a+b), annulus D_o−D_i. Not Q=Av, not Manning Q, not Reynolds, not Darcy. (calculation_version 1.0.0)"
}