Abstract:Composite porous media embedded with impermeable spheres are widely used in the field of groundwater seepage

water flows through impermeable spheres in porous media due to the influence of impermeable spheres

and the closer the sphere is

the more obvious the phenomenon is. In order to get the seepage field and equivalent permeability coefficient

nonlinear Darcy Brinkman-extended equation was applied in spherical coordinates. With no slippage on sphere and the unidirectional uniformed flow at infinity as the boundary conditions

analytical solution of seepage velocity and pressure around the sphere was obtained .By analyzing the expression of the analytical solution

the results showed the velocity and pressure of the seepage field are related to the permeability of the porous media and the dynamic viscosity coefficient of the groundwater. On this basis

the Darcy averaged flow was obtained via integral of velocity to calculate the equation of equivalent permeability coefficient

the theory proves that the relative size of the sphere and the porous medium was the most important factor to affect the permeability coefficient of the composite. Finally

a certain graded sand was used as a porous medium

three kinds of organic glass spheres with diameters of 4cm

6cm and 8cm were used as impervious spheres

the seepage test was carried out by self-made test equipment. In the experiment

the degree of compaction of the porous media was controlled to keep its permeability coefficient almost unchanged

and the seepage experiment was carried out by changing the impervious sphere filled in the porous medium. Three groups of experiments were performed on each impervious sphere

and the mean value was taken as the test result. The equivalent permeability coefficient deviations between test results and theoretical calculation were small

correctness of the calculation of porous medium seepage field embedded with impermeable sphere was verified.