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Hazen-Williams Flow Rate Calculator

Calculate water flow rate in pressurised pipes using the Hazen-Williams equation given pipe diameter, hydraulic gradient, and C factor. Widely used by civil engineers for water main and irrigation system design.

Pipe Diameter (m)

Hydraulic Gradient (m/m)

Hazen-Williams C Factor

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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.

Orifice Area (m²)

Discharge Coefficient

Pressure Difference (Pa)

Fluid Density (kg/m³)

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Key differences

	Hazen-Williams Flow Rate Calculator	Orifice Flow Discharge Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	3	4
Result	Flow Rate (m³/s)	Flow Rate (m³/s)
What it does	Calculate water flow rate in pressurised pipes using the Hazen-Williams equation given pipe diameter, hydraulic gradient, and C factor. Widely used by civil engineers for water main and irrigation system design.	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.