Flow characteristics of tetra-n-butyl ammonium bromide clathrate hydrate slurry in 90° elbow pipe.

Abstract

Tetra-n-butyl ammonium bromide (TBAB) clathrate hydrate slurry (CHS) is commonly used as a cold storage medium and secondary refrigerant in the secondary-loop refrigeration. In the present study, the flow characteristics of TBAB CHS in an elbow pipe were numerically investigated using Euler-Euler multiphase model, which was validated by comparing the numerical pressure drops with the experimental evidences. The numerical investigation was carried out at inlet velocity within a range of 1.0~3.0 m/s and inlet solid volume fraction within a range of 5.0~40.0 vol%. The numerical results showed that the solid particle distribution was more uniform at higher inlet velocity and solid volume fraction. Furthermore, in the elbow section, the primary flow accelerated near the inner wall and a secondary flow caused by the centrifugal force occurred on the cross-section of elbow section, which made solid particles agglomerate to the outer wall of the elbow section.