DOT 49 CFR § 173.318 • CGA H-3 • THERMODYNAMIC HEAT FLUX HUD

Liquid Hydrogen Cryo-Vessel Boil-Off Rate & Venting Hold-Time Calculator

Simulate vacuum annulus degradation, ambient solar heat ingress, daily boil-off rate (BOR %/day), vapor pressure rise, and regulatory One-Way Travel Time (OWTT) before safety valve discharge.

Cryogenic Tanker Parameters

ANNULAR VACUUM (MICRONS HG): 3.5 Microns (High Vacuum)
< 5µ (Factory MLI) 25µ (Degraded) 100µ (Loss of Vacuum)
AMBIENT ROAD TEMPERATURE: 85°F (29.4°C)
0°F (Winter) 70°F (Nominal) 115°F (Desert Summer)
Daily Boil-Off (BOR)
0.42% / Day
Normal Evap Rate
Heat Ingress (Q)
98.4 Watts
MLI Radiation + Conduction
Total Hold-Time
178 Hours
7.4 Days to 150 PSIG
DOT Max Transit
154 Hours
49 CFR § 173.318 OWTT

LIVE PRESSURE BUILDUP & VENT TIMELINE HUD

DOT § 173.318: PASS
SRV Setpoint: 150 PSIG Loading: 25 PSIG DOT Limit: 154h Venting at 178h 0h (Departure) Highway Transit Hours →
HOURLY PRESSURE BUILDUP 0.70 PSI / Hour
DAILY MASS LOSS VAPORIZED 19.1 kg / Day (42.1 lbs)
SPIN CONVERSION HEAT 3.5 W (Exothermic)

Request Cryogenic Venting & Hold-Time Certification

Receive certified DOT 49 CFR § 173.318 hold-time calculations, route thermal simulations, and emergency safe-haven diversion plans.