09. Heat and Mass Transfer

Emergency shut-off valves (ESVs) serve as critical safety components in the management of boil-off gas from Liquid Hydrogen (LH2) storage tanks, ensuring the prevention of potential property damage and health hazards. This paper focuses on conducting a comprehensive analysis of the ESV's performance under fully closed, partially opened, and fully opened conditions, specifically with liquid hydrogen (LH2) as the working fluid. To achieve this, the study employs the widely used commercial solver, ANSYS CFX, to execute both thermal and flow analyses. One key aspect of the analysis involves estimating the convective heat transfer coefficients within the horizontal and vertical pipes of the ESV. This estimation is accomplished through established correlations that take into account the Raleigh number, a critical parameter in understanding the flow behavior. The detailed thermal and flow analysis using ANSYS-CFX enables the evaluation of the ESV's efficiency and reliability under various operational states. The obtained results furnish crucial insights into temperature distributions and flow velocities within the ESV. These findings hold great significance for enhancing the ESV's design process, contributing to the optimization of its performance and safety standards. By elucidating the thermal and flow characteristics specific to hydrogen, this research aids in the development of ESVs that can reliably and effectively safeguard LH2 storage facilities and their surrounding environments, mitigating potential risks associated with cryogenic gas management.