多孔介质特性对Rayleigh-Taylor不稳定性现象的影响OA

The study of RTI(Rayleigh-Taylor instability)in porous media is often used to study the occurrence and evolution of fluid-to-fluid instability,to analyze and avoid the occurrence of unfavorable factors in practical applications,and to study the formation mechanism of shale in rock and soil.The lattice Boltzmann method was used to simulate and analyze RTI phenomenon between two miscible fluids in porous media at the representative elementary volume scale herein.The effects of porosity,permeability of porous media and interface perturbations on RTI phenomenon were studied.The results show that after instability occurs,a vortex flow forms at the interface.The fluid particles accumulate at the interface under the action of forces,causing the density of the interface to be slightly higher than that of the fluid in other areas.As time progresses,the streamlines change from a vortex shape to multiple irregular small vortices,and the speed of heat transfer and intermixing of the fluid increases.The fluid can form fingers and bubbles at the interface and produce unstable phenomenon when the permeability K is large enough.The research offers a new perspective for calculating large-scale and large-data seepage fields.