Research on Multiphase Flow Performance in Steam Injection Wellbore and Its Application

摘要

This paper mainly focuses on the study of multiphase flow performance in steam injection wellbore, the analysis of hydrodynamic and thermodynamic properties in the process of steam injection, and analyzing the dynamic parameters in steam injection wellbore by combining actual flow performance on the basis of research results as well. The research on multiphase flow performance in steam injection wellbore includes both laboratory experiments and theoretical analysis. The experiments are performed on the set-up with the function of arbitrarily adjustable inclination angle of pipe. The experimental results cover flow pattern, pressure drop and void ratio under various gas-liquid ratios and inclined angles. The flow pattern criteria and the correlations of pressure drop with gas-liquid ratios and inclined angles for multiphase flow in inclined pipes are presented by means of processing a lot of experimental data. A universal equation governing one-dimension gas-liquid two-phase flows is obtained based on the assumption of local instantaneous equilibrium of flow and differential-element average in space. By using the separated flow model and the homogeneous flow model, a comprehensive model of calculating the pressure drop, the correlations of liquid holdup and friction factor for multiphase flow in inclined pipes are proposed taking into account the characteristics of multiphase flow in petroleum engineering. The comparison between the lab experiments and actual measurement data shows that the theoretically calculated results are reasonable, and they can be consistent with the actual measurement data. This model is applicable for commingled gas injection, layered steam injection, and SAGD as well, it can also provide theoretical basis for down-hole layered steam injector.