Abstract: Eulerian-Eulerian model was applied to conduct 3D CFD (Computational Fluid Dynamics) numerical simulation of the gas-liquid flow in the outlet pipeline of the heating furnace in hydrorefining unit. The distribution of the concentration field and velocity field of gas-liquid phase under the existing pipeline structure were studied and the optimization of the pipeline arrangement was proposed. The research results indicate that due to the different inertia forces of gas and liquid, a spiral flow was formed in the pipeline in the existing pipeline arrangement scheme after the gas-liquid flow changing multiple directions in the 3D space; by optimizing the arrangement scheme, the driving force along the radial rotationwas partially eliminated and the spiral flow of the fluid was reduced. The research results can provide guidance for the optimization of the arrangement scheme for the outlet pipeline of heating furnace.

Key words: heating furnace, outlet pipeline, gas-liquid two-phase flow, numerical simulation