Numerical study of helium piping structures under natural convection on thermal performance in liquid helium portable tank

Abstract This study presents a numerical investigation into the influence of helium piping configurations under natural convection on temperature variation and flow rate fluctuations during the storage of liquid helium in liquid helium portable tank. The physical model and mathematical model for the liquid helium portable tank and its pipe connection are developed. The performance of straight, single-curved, and double-curved helium piping structures are compared to elucidate the relationship between helium piping design and mass flow variations. The results reveal a minimum velocity of 0.339 m/s and a pipe gas seal position section temperature of 137 K at 540 s. Notably, the single-curved tube configuration demonstrates a reduced sensitivity to natural convection effects and extends the helium holding time by three days. The research not only offers a simplified and practical alternative to the more complex double-tube model, but also provides valuable insights for the optimal design of helium piping structures in liquid helium portable tank.