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Tank Drain Time Calculator

Calculate how long it takes to drain a tank from one liquid level to another through a bottom orifice. Ideal for sizing drain valves, planning tank cleanouts, or verifying emergency drainage rates.

Initial Liquid Height (m)

Final Liquid Height (m)

Tank Cross-Section Area (m²)

Drain Orifice Area (m²)

Discharge Coefficient

Fill in the required fields to see your result.

Fluid Mechanics

Orifice Flow Calculator

Calculate volumetric flow rate through an orifice plate or sharp-edged opening given pressure drop and fluid properties. Widely used for flow metering in industrial pipelines and process plants.

Orifice Diameter (m)

Pressure Difference (Pa)

Fluid Density (kg/m³)

Orifice Type

Beta Ratio (d/D)

Fill in the required fields to see your result.

Key differences

	Tank Drain Time Calculator	Orifice Flow Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	5	5
Result	Drain Time (seconds)	Flow Rate (m³/s)
What it does	Calculate how long it takes to drain a tank from one liquid level to another through a bottom orifice. Ideal for sizing drain valves, planning tank cleanouts, or verifying emergency drainage rates.	Calculate volumetric flow rate through an orifice plate or sharp-edged opening given pressure drop and fluid properties. Widely used for flow metering in industrial pipelines and process plants.