Numerical investigation of slush nitrogen flow in a horizontal pipe

Slush nitrogen is a cryogenic two-phase fluid containing solid particles in liquid nitrogen, and the flow of slush nitrogen in a horizontal pipe is investigated using the 2D Eulerian–Eulerian multiphase approach. The per-phase k–ε turbulence model is used in the study to model the turbulent two-phase flow, and the motion of solid phase is modeled by the kinetic theory of granular flow to account for both particle–particle and particle–wall interactions. The 2D multiphase model is firstly validated with solid volume fraction and velocity profile data of several different slurry flows from the open literature, and then is further applied to studying slush nitrogen flow in a horizontal pipe, and the numerical solid velocity profiles are compared with the experimental data. The effects of the flow velocity and the mean solid volume fraction on the flow characteristics of slush nitrogen are investigated numerically in this study.

► The kinetic theory of granular flow is applied to slush nitrogen. ► Model parameters proper for slush nitrogen are determined by sensitivity analysis. ► Numerical results agree well with the experimental data. ► Solid volume fraction profile of slush nitrogen is predicted with the developed model.