LNG Tank - Displacement Purge Volume
Nitrogen volume required for a displacement (layered, density-driven) purge - used to inert LNG cargo tanks before gassing-up, ~1.05× tank volume when well-controlled.
Tank volumes required
1.05× V
N₂ volume
26,316m³
Formula, assumptions, and limits
Displacement requires a distinct density interface - N₂ (1.25 kg/m³) displaces hot air upward; methane vapor later displaces N₂ downward. Poor interface control collapses efficiency to dilution behaviour.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Tank gross volume | m³ | capacity plan | |
| Displacement efficiency | - | SIGTTO guidance |