Sharp‑Edged Orifice (Free & Submerged – Advanced)

Rectangular & circular orifices with discharge, jet velocity, flow regime auto‑detection and modular ratio. Supports SI (m, m³/s) and US (ft, ft³/s) units.

Weirs & Orifices · Advanced Free & submerged Flow regime auto‑detection Rectangular & circular

Input Parameters

Orifice in a vertical wall between two reservoirs. Specify geometry, upstream head above orifice centre and downstream head (0 = discharging to atmosphere).

Orifice & units
Geometry
Heads
Discharge coefficients

General form: Q = C · A · √(2 g ΔH) where ΔH = max(H₁ − H₂, 0) is the head difference. Modular ratio is reported as m = Q / Qideal.

Results & Exports

Area A –
Head difference ΔH –
Submergence ratio H₂/H₁ –
Ideal discharge Qideal (m³/s) –
Actual discharge Q (m³/s) –
Jet velocity V = Q/A (m/s) –
Modular ratio m –

Flow regime is based on downstream head: H₂ ≈ 0 → free discharge, 0 < H₂ < H₁ → submerged orifice, H₂ ≥ H₁ → no effective driving head.

0 records Calculation history
# Units Shape Dims A H₁ H₂ ΔH Cideal Cused Regime Qideal Q V m = Q/Qideal
Tool assumes a sharp‑edged, thin orifice and steady, incompressible flow. For thick plates, mouthpieces, or complex approach conditions, use project‑specific corrections or lab‑derived coefficients.

Reference Schematic (not to scale)

Orifice in a vertical wall between upstream and downstream reservoirs. H₁ and H₂ are measured vertically to the orifice centreline. ΔH = H₁ − H₂.

H₁ H₂ Flow →