Dual-scale insights of two-phase flow in inter-cleats based on microfluidics:Interface jumps and energy dissipation  

作　　者：Jicheng Zhang Dawei Lv Jon Jincai Zhang Feng Wang Dawei Yin Haiyang Yu 

机构地区：[1]College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China [2]College of Earth Science and Engineering.Shandong University of Science and Technology,Qingdao 266590,China [3]Sinopec Tech Houston,Houston 77041,USA

出　　处：《International Journal of Mining Science and Technology》2025年第3期451-465,共15页矿业科学技术学报(英文版)

基　　金：the financial support from the National Natural Science Foundation of China (No.42102127);the Postdoctoral Research Foundation of China (No.2024 M751860)。

摘　　要：Cleat serves as the primary flow pathway for coalbed methane(CBM)and water.However,few studies consider the impact of local contact on two-phase flow within cleats.A visual generalized model of endogenous cleats was constructed based on microfluidics.A microscopic and mesoscopic observation technique was proposed to simultaneously capture gas-liquid interface morphology of pores and throat and the two-phase flow characteristics in entire cleat system.The local contact characteristics of cleats reduced absolute permeability,which resulted in a sharp increase in the starting pressure.The reduced gas flow capacity narrowed the co-infiltration area and decreased water saturation at the isotonic point in a hydrophilic environment.The increased local contact area of cleats weakened gas phase flow capacity and narrowed the co-infiltration area.Jumping events occurred in methane-water flow due to altered porosity caused by local contact in cleats.The distribution of residual phases changed the jumping direction on the micro-scale as well as the dominant channel on the mesoscale.Besides,jumping events caused additional energy dissipation,which was ignored in traditional two-phase flow models.This might contribute to the overestimation of relative permeability.The work provides new methods and insights for investigating unsaturated flow in complex porous media.

关 键 词：Inter-cleat MICROFLUIDICS Two-phase flow Dual-scale Interface jump Inertial effect 

分 类 号：O35[理学—流体力学]