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    "Rectangular broad-crested weir: Q = C_d (2/3)^{3/2} b √g H^{3/2}; default C_d=0.85; modular free nappe; C_d is an input in (0, 1]",
    "H is upstream head above the crest, not energy head; optional L_c envelope H/L_c∈[0.08,0.50]; optional P with H/P≤1.5",
    "Not thin-plate (2/3) C_d L √(2g) H^{3/2}, not Manning n, not Q=Av, not orifice C_d A √(2gH), not Francis 3.33 L H^{3/2}"
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    "Rectangular broad-crested weir: Q = C_d (2/3)^{3/2} b √g H^{3/2}; default C_d=0.85; modular free nappe; C_d is an input in (0, 1]",
    "H is upstream head above the crest, not energy head; optional L_c envelope H/L_c∈[0.08,0.50]; optional P with H/P≤1.5",
    "Not thin-plate (2/3) C_d L √(2g) H^{3/2}, not Manning n, not Q=Av, not orifice C_d A √(2gH), not Francis 3.33 L H^{3/2}"
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      "section": "Modular rectangular broad-crested weir",
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      "supports": "Q = C_d (2/3)^{3/2} b √g H^{3/2}; modular H/L_c range",
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      "title": "ISO 80000-4 — Mechanics",
      "section": "Volume flow rate",
      "url": "https://www.iso.org/standard/31895.html",
      "supports": "Q is volume flow; H and b are lengths",
      "kind": "standard"
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    {
      "title": "Bos, M.G. Discharge Measurement Structures",
      "section": "Broad-crested weirs",
      "supports": "Critical-flow rectangular broad-crested discharge; C_d of order 0.85",
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