泡沫油运动形态的可视化研究

VISUALIZATION STUDY ON FOAMY OIL FLOW STATE

委内瑞拉Orinoco地层油复杂的"泡沫油"流动特征在油藏开发及实验室研究中受到高度重视,不同压力下的泡沫油微观形态研究对探寻渗流机理尤为重要。低于泡点压力时泡沫油表现出复杂的形态变化,实验利用可视化模型观察和分析了气泡的形成、生长过程、合并和分裂现象,并发现气泡通过孔隙时具有独特的运移特征:当气泡接近和通过孔喉时,运移速度明显加快。不同直径的气泡伴随有变形、翻转和吸附等形式。对模型表面粗糙度、孔隙大小、气泡尺寸等因素进行分析后,发现气油比是影响气泡数量的关键因素,但其不是气/液界面相互作用的主要因素。气泡的产生及运动过程受压降和重质组分的双重作用,高沥青质、胶质含量决定了泡沫油的渗流特征。

The foamy oil in the Orinoco Formation,Venezuela,is placed great attention to for its flow characteristic in development and lab research.Under different pressure,the research on the microscopic shape of the oil is important to search for the mechanism flowing through porous media.When the foamy oil is under bubble point pressure,it presents complex shape change,in lab research,by means of visualization model,the formation,growth,merging and separating of the bubble are observed and analyzed,it is found out the bubble,while passing through pores,is of unique migration characteristic,when the bubble comes close to or pass pore throats,its motion speed increases considerably.Deformation,overturning or absorbtion will occur in different diameter bubbles.Analysis of model surface roughness,pore and bubble size indicates the key factor influencing the number of bubbles is gas oil ratio,but the ration is not major factor gas/liquid interface interacting.The generation and motion of the bubble are controlled by both pressure drop and heavy weight components,high asphaltum and collidal matter content determine the characteristic flowing through porous media of foamy oil.