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Fluid Mechanics

Orifice Flow Discharge Calculator

Calculates the volumetric flow rate through an orifice plate or opening given the upstream-to-downstream pressure difference. Used in flow metering, tank drainage design, and hydraulic control systems.

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Fluid Mechanics

Manning's Roughness Flow Calculator

Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.

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Key differences

Orifice Flow Discharge CalculatorManning's Roughness Flow Calculator
CategoryFluid MechanicsFluid Mechanics
Inputs required43
ResultFlow Rate (m³/s)Flow Velocity (m/s)
What it doesCalculates the volumetric flow rate through an orifice plate or opening given the upstream-to-downstream pressure difference. Used in flow metering, tank drainage design, and hydraulic control systems.Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.