Study on thermohydrodynamic responses of liquid hydrogen in baffled tankers during braking process

There is a growing demand for hydrogen as a clean fuel. Liquid hydrogen (LH₂) tankers, as a suitable method for long-distance and large-scale hydrogen transportation, are highly susceptible to instantaneous variations in thermodynamic response for safety performance. This paper constructs a computational fluid dynamics (CFD) model to predict the variation of sloshing behavior and thermodynamic properties in LH₂ tankers during braking processes. The effects of baffles, filling levels, and accelerations on thermohydrodynamic responses are discussed in detail. Model validation is carried out to guarantee the accuracy of the numerical calculation. The results showed that the phase interface fluctuation, which makes full contact between the LH₂ and the superheated hydrogen, is the main factor accelerating the evaporation rate of LH₂ in tankers. The heat transfer between the baffles and the fluid is constantly varying during braking processes due to the “thermal bridge” effect and the temperature difference between them. Baffles significantly inhibit the accelerated evaporation rate of LH₂ due to violent sloshing under braking. The filling level is beneficial for LH₂ tankers’ stable transportation, but it increases the evaporation rate. The maximum von Mises stress occurs at the bottom of the baffles connected to the tank wall, whereas the maximum displacement occurs at the liquid flow hole. The pressure increases by 350.16 Pa in 16 s when the braking acceleration is 1.25 m/s² and by 1070.59 Pa in 4 s when the acceleration is 5 m/s². Under 5 m/s² acceleration, the pressurization rate is 340 times greater than in the stable state, which is 0.22 h/kPa. This study can provide technical references for LH₂ tankers’ sloshing and heat leakage controls.