Zhang Moxi, Chen Xinglong, Lyu Weifeng
University of Chinese Academy of Sciences, Beijing 100049, China.
Institute of Porous Flow and Fluid Mechanics, Chinese Academy of Sciences, Langfang 065007, China.
Molecules. 2025 Mar 5;30(5):1163. doi: 10.3390/molecules30051163.
This study systematically investigates the formation mechanism and development characteristics of the "foamy oil" phenomenon during pressure depletion development of high-viscosity crude oil through a combination of physical experiments and numerical simulations. Using Venezuelan foamy oil as the research subject, an innovative heterogeneous pore-etched glass model was constructed to simulate the pressure depletion process, revealing for the first time that bubble growth predominantly occurs during the migration stage. Experimental results demonstrate that heavy components significantly delay degassing by stabilizing gas-liquid interfaces, while the continuous gas-liquid diffusion effect explains the unique development characteristics of foamy oil-high oil recovery and delayed phase transition-from a microscopic perspective. A multi-scale coupling analysis method was established: molecular-scale simulations were employed to model component diffusion behavior. By improving the traditional Volume of Fluid (VOF) method and introducing diffusion coefficients, a synergistic model integrating a single momentum equation and fluid volume fraction was developed to quantitatively characterize the dynamic evolution of bubbles. Simulation results indicate significant differences in dominant controlling factors: oil phase viscosity has the greatest influence (accounting for 50%), followed by gas component content (35%), and interfacial tension the least (~15%). Based on multi-factor coupling analysis, an empirical formula for bubble growth incorporating diffusion coefficients was proposed, elucidating the intrinsic mechanism by which heavy components induce unique development effects through interfacial stabilization, viscous inhibition, and dynamic diffusion. This research breaks through the limitations of traditional production dynamic analysis, establishing a theoretical model for foamy oil development from the perspective of molecular-phase behavior combined with flow characteristics. It not only provides a rational explanation for the "high oil production, low gas production" phenomenon but also offers theoretical support for optimizing extraction processes (e.g., gas component regulation, viscosity control) through quantified parameter weightings. The findings hold significant scientific value for advancing heavy oil recovery theory and guiding efficient foamy oil development. Future work will extend to studying multiphase flow coupling mechanisms in porous media, laying a theoretical foundation for intelligent control technology development.
本研究通过物理实验与数值模拟相结合的方法，系统地研究了高粘度原油压力衰竭开发过程中“泡沫油”现象的形成机理和发展特征。以委内瑞拉泡沫油为研究对象，构建了一种创新的非均质孔隙蚀刻玻璃模型来模拟压力衰竭过程，首次揭示了气泡生长主要发生在运移阶段。实验结果表明，重组分通过稳定气液界面显著延迟脱气，而连续的气液扩散效应从微观角度解释了泡沫油的独特发展特征——高采收率和延迟相变。建立了一种多尺度耦合分析方法：采用分子尺度模拟来模拟组分扩散行为。通过改进传统的流体体积（VOF）方法并引入扩散系数，开发了一种将单动量方程和流体体积分数相结合的协同模型，以定量表征气泡的动态演化。模拟结果表明主导控制因素存在显著差异：油相粘度影响最大（约占50%），其次是气体组分含量（约占35%），界面张力影响最小（约占15%）。基于多因素耦合分析，提出了一个包含扩散系数的气泡生长经验公式，阐明了重组分通过界面稳定、粘性抑制和动态扩散诱导独特发展效应的内在机制。本研究突破了传统生产动态分析的局限性，从分子相行为与流动特性相结合的角度建立了泡沫油开发的理论模型。它不仅为“高产油、低产气”现象提供了合理的解释，还通过量化参数权重为优化开采工艺（如气体组分调控、粘度控制）提供了理论支持。这些发现对于推进稠油开采理论和指导高效泡沫油开发具有重要的科学价值。未来的工作将扩展到研究多孔介质中的多相流耦合机制，为智能控制技术的发展奠定理论基础。
