悬浮微粒在被加热多孔介质内的沉积与运移特性

通过建立沿管壁恒热流加热的渗流实验系统,实验研究了悬浮颗粒在饱和多孔介质内以及入口界面处的沉积和运移特性。着重研究了有无加热条件,以及不同加热温差,相同多孔介质和进口悬浮液浓度情况下,实验段入口界面处与内部的颗粒沉积量变化,以及沿程不同位置处的压力变化。并对实验过程中的渗流稳定性及各测点温度和多孔介质段渗透系数进行了分析。结果表明:相对渗透率k_t/k₀在不同温差下有明显不同;多孔介质与进口流体界面处的沉积量随温差的增大而增加,沉积结构的稳定性降低;多孔介质段颗粒沉积强度随温差的增大而增大,实验结果可为今后的理论分析提供验证依据。

Deposition and transportation characteristics of suspended microparticles in water through heated porous media column

The deposition and transportation characteristics of microparticles suspended water flowing vertically downwards through a heated porous column were experimentally studied. The amount of deposited particles at the interface and inside porous column, and pressure change at difference location at the conditions with and without circumference heating, or the effect of temperature gradient perpendicular to the flow direction were focused in this study, in which the porous columns and inlet concentration of suspended fluid were kept the same. In addition, the seepage stability, the tube wall temperature distribution and the relative permeabilities for each section were analyzed. The results showed that the relative permeability k_t/k₀ was obviously different at different heating temperature gradients while having the same original porous media and inlet concentration of suspensions. The deposition rates both at the entrance interface and inside porous medium increased with an increase of temperature difference, however, the stability of the deposited structure decreased.