Leak Rate Calculator Q = ΔP·V/t

Calculate Leakage Rate Parameters
Select Answer Mode
Pressure Loss (ΔP) [?]

Test Volume (V) [?]

Test Duration (t) [?]

Leak Rate (Q_L) [?]

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Contents

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User Guide

This tool will calculate any parameter from the formula for leakage rate for a pressurised enclosed space, which includes the difference in pressure from the start to the finish of leak test, the total volume of the space being tested, the elapsed time of the leak test, and the average leakage rate.

Formulas

The formulas used by this leakage rate calculator to determine each individual parameter are:

ΔP = Q_L · t / V

V = Q_L · t / ΔP

t = ΔP · V / Q_L

Q_L = ΔP · V / t

Symbols

ΔP = Pressure loss
V = Test volume
t = Test duration time
Q_L = Leak rate

Pressure Loss (ΔP)

This is how much the pressure drops a leak test.

Test Volume (V)

This is the total internal volume of the vessel being tested.

Test Duration Time (t)

This is the time taken for the pressure to drop during a leak test.

Leak Rate (Q_L)

This is a measure of the rate of gas loss from a test volume over the duration of the leak test. It is intended to provide a measure of the proportion of the total gas that has escaped, so that the same pressure loss for a larger sized volume would result in a larger leak rate value.

The following leak rate units can be used with this calculator:

millibar litres per second (mbar·L/s)
pascal cubic metres per second (Pa·m³/s)
pascal litres per second (Pa·L/s)
standard litres per minute (atm·L/min, slm, slpm)
standard cubic millimetres per second (atm·mm³/s)
standard cubic centimetres per second (atm·cm³/s, sccs)
standard cubic centimetres per minute (atm·cm³/min, sccm)
standard cubic centimetres per hour (atm·cm³/h)
standard cubic metres per minute (atm·m³/min)
standard cubic feet per minute (atm·ft³/min)
standard cubic feet per year (atm·ft³/yr)
micron of mercury litres per second (µHg·L/s, lusec)
micron of mercury cubic feet per minute (µHg·ft³/min, µHg·cfm)
micron of mercury cubic feet per hour (µHg·ft³/h)
torr litres per second (Torr·L/s)