{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://www.calculatorx.com/schemas/physics.fluid.pipe_bend/1.0.0/input.json",
  "title": "Pipe bend — input",
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "mode": {
      "type": "string",
      "enum": [
        "head",
        "pressure",
        "velocity",
        "angle"
      ],
      "description": "head (default), pressure, velocity, or angle. Not minor-loss, mitered, Darcy, or Q=Av."
    },
    "v_m_s": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Mean speed in m/s. Required except velocity invert. Alternative: speed. Do not send query v (that is calculation_version)."
    },
    "speed": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Mean speed in m/s (REST alias of v_m_s)."
    },
    "theta_deg": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Bend deflection in degrees. Required except angle invert. Alternative: theta_rad. Do not send both. Range (0, 180]."
    },
    "theta_rad": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Bend deflection in radians. Alternative: theta_deg. Do not send both."
    },
    "rd": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Centerline radius over diameter R/D. Required. Alternatives: r_d, R_D, r_over_d. Require R/D ≥ 1."
    },
    "r_d": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "R/D alias of rd."
    },
    "h": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Head loss in m. Required for velocity and angle invert. Alternatives: hm, h_m."
    },
    "h_m": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Head loss in m (query/UI). REST may send h."
    },
    "rho": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Density in kg/m³. Optional; default 1000."
    },
    "g": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Gravity in m/s². Optional; default 9.80665."
    }
  },
  "description": "Circular-arc bend h=K v²/(2g), K=0.21 (θ/90)/√(R/D). Not minor-loss K given, not mitered, not Darcy, not Q=Av. (calculation_version 1.0.0)"
}