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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

Venturi Meter Calculator

Determine the volumetric flow rate through a pipe using upstream and throat pressure readings from a Venturi meter. Ideal for engineers verifying flow in water treatment, HVAC, and chemical process pipelines.

Throat Diameter (m)

Pipe Diameter (m)

Pressure Difference (Pa)

Fluid Density (kg/m³)

Venturi Type

Fill in the required fields to see your result.

Key differences

	Tank Drain Time Calculator	Venturi Meter 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.	Determine the volumetric flow rate through a pipe using upstream and throat pressure readings from a Venturi meter. Ideal for engineers verifying flow in water treatment, HVAC, and chemical process pipelines.