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Hello sir/madam, can you please explain me how to calculate the volume of compressed hydrogen gas filled in a cylinder.
To find the volume of gas available from a compressed gas cylinder, apply the Ideal Gas Law (PV = nRT).

In a high-pressure cylinder, the volume will be affected by the content's comprehensibility factor Z (PV = ZnRT).

The Ideal Gas Law PV = nRT

Where:

P is pressure

V is volume

n is the number of moles

R is the gas constant

T is the absolute temperature

When the temperature is kept constant, we can derive the equation:

P (1) x V (1) = P (2) x V (2)

Where:

P (1) is the pressure of the compressed gas in the cylinder (psi)

V (1) is the internal volume of the cylinder, often referred to as water volume (liter)*

P (2) is the atmospheric pressure (1 atm - 14.7 psi)

V (2) is the volume of gas at pressure P (2) (liter).

For example, an AL sized cylinder is filled with nitrogen at 2000 psi. What is the gas volume of nitrogen from the cylinder?

P (1) is 2000 psi

V (1) is the internal volume of AL cylinder 29.5 liter*

P (2) is 14.7 psi

V (2) is the unknown volume of gas

Solving the equation above for V (2) gives:

V (2) = [p (1) x V (1)]/P (2) = (2000 psi x 29.5 liters)/14.7 psi = 4013 liters (approximately 140 cu. ft.)

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