H2 Purge Cycles
Settled Pressure
Fill Amount
Energy & Range
About this calculator
This calculator is just a basic tool made to easily figure out the volume or mass of hydrogen at pressure.
Boyle's law is fine and dandy until the pressures get higher and start to deviate from the actual value.
The base calculation comes from the paper, "Revised Standardized Equation for Hydrogen Gas Densities for Fuel Consumption Applications" (link) by Eric W. Lemmon, Marcia L. Huber (National Institute of Standards and Technology), and Jacob W. Leachman (University of Wisconsin-Madison Cryogenics Lab); published in the Journal of Research of the National Institute of Standards and Technology, dated July 22, 2008.
Calculation simplified in order to be able to calculate mass, volume, pressure, or temperature using various units.
The equation is solved directly for mass and volume. Pressure and temperature cannot be isolated algebraically — both appear inside several fractional powers — so those are found numerically instead, by searching for the value that reproduces the figures you entered.
Valid range. Results are only meaningful for gaseous hydrogen roughly between 200–1200 K and up to about 200 MPa. Outside that the underlying correlation is being extrapolated and the numbers should not be trusted. When solving for pressure or temperature the calculator only searches inside that range.
Boyle's law is fine and dandy until the pressures get higher and start to deviate from the actual value.
The base calculation comes from the paper, "Revised Standardized Equation for Hydrogen Gas Densities for Fuel Consumption Applications" (link) by Eric W. Lemmon, Marcia L. Huber (National Institute of Standards and Technology), and Jacob W. Leachman (University of Wisconsin-Madison Cryogenics Lab); published in the Journal of Research of the National Institute of Standards and Technology, dated July 22, 2008.
Calculation simplified in order to be able to calculate mass, volume, pressure, or temperature using various units.
The equation is solved directly for mass and volume. Pressure and temperature cannot be isolated algebraically — both appear inside several fractional powers — so those are found numerically instead, by searching for the value that reproduces the figures you entered.
Valid range. Results are only meaningful for gaseous hydrogen roughly between 200–1200 K and up to about 200 MPa. Outside that the underlying correlation is being extrapolated and the numbers should not be trusted. When solving for pressure or temperature the calculator only searches inside that range.
Disclaimer
This calculator is provided free of charge, as is and without warranty of any kind, express or implied, including but not limited to warranties of accuracy, merchantability or fitness for a particular purpose.Results may be wrong. The equation is an approximation, it is applied here in a simplified form, and the implementation may contain errors. Do not rely on these numbers for anything involving safety, regulatory compliance, custody transfer, or engineering decisions without verifying them independently against an authoritative source and the judgement of a qualified engineer.
Hydrogen is flammable over a very wide range in air, ignites with very little energy, and is stored at pressures that are dangerous on their own. Purging and handling procedures must come from your own competent safety assessment, not from a web page.
To the fullest extent permitted by law, the author accepts no liability for any loss, injury, or damage of any kind arising from use of this calculator or reliance on its output. You use it entirely at your own risk.