Gas blender
Partial-pressure fill procedure from the gases you actually have.
Target
The mix and pressure you want in the cylinder when the fill is done.
%
%
bar
AL80 is stamped 207 bar.
Target is EAN32 — 32.0/0.0/68.0
Cylinder now
What the analyser reads and what the gauge shows before you start.
Water volume 11.1 L.
%
%
bar
Zero for an evacuated cylinder.
Fill stationWhich banks are connected, and how the gas behaves while you fill.3 banks · ideal gas
- Helium0.0/100.0/0.0
- Oxygen100.0/0.0/0.0
- Air21.0/0.0/79.0
°C
A fast fill runs hot; the cylinder loses pressure as it cools.
Equation of state
Real-gas corrections matter above roughly 200 bar. The planner falls back to the ideal gas law, and says so, where van der Waals is not meaningful.
Resulting mix
EAN32
32.0/0.0/68.0
Final pressure
200bar
Target 200 bar
Max depth
33m
at ppO₂ 1.40
Density at MOD
5.20g/L
limit 5.70 g/L
Blend procedure
Add each gas in order, stopping at the running total.
| Step number | Action | Pressure change in bar | Running total in bar |
|---|---|---|---|
| 1 | Add Oxygen | +28 | 28 |
| 2 | Add Air | +172 | 200 |
Solved with the ideal gas equation of state at 20°C. Analyse the cylinder before diving; a plan is not an analysis.