Numerical Simulation Research on Precooling Characteristics of LNG Discharge Pipeline


  • L Zejun
  • W Chunsheng
  • C Mingyu
  • S Qiji



The low-temperature fluid flowing into the LNG unloading pipeline will cause violent heat exchange phenomenon, resulting in damage to the pipeline and affecting normal operation. Therefore, pre-cooling treatment is required in advance. Considering the fluid-solid heat transfer and fluid flow characteristics comprehensively, multi-physics coupling simulation study on the pre-cooling problem of the LNG discharge pipe with a π-shaped elbow is carried out. The analysis from BOG and LNG pre-cooling processes respectively shows that: the fluid with low temperature and high density is mainly concentrated at the bottom of the pipe and outside the bend, the wall temperature has a sudden drop at the bend, and there is a large temperature difference between the gas side and the liquid side wall surface. Mixed convection heat exchange mainly occurs in the tube. There will be a small area of natural convection-dominated heat exchange state in the elbow and the downstream pipe section.



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How to Cite

Zejun, L., Chunsheng, W., Mingyu, C. and Qiji, S. (2020) “Numerical Simulation Research on Precooling Characteristics of LNG Discharge Pipeline”, The International Journal of Multiphysics, 14(3), pp. 273-289. doi: 10.21152/1750-9548.14.3.273.