Difficult techniques for permeability test of low permeability medium such as long testing time(lasting one week), sample sealing performance under high temperature(less than 90 ℃ ),accuracy of micro-flow measuring, uniformity and constancy of testing temperature during test are solved.

The experimental research and field practice demonstrate that the nonlinearity of percolation flow and variability of flow regime are the main flow features in the complicated lowpermeability media, and are also the difficult problems being concerned widely in the field of current percolation flow dynamics.

Talking about the Influence of Effective Pressure on Low Permeating and Porous Medium Permeability;

Many researches show that the fluid flow in low permeability media doesn't obey the Darcy's law, and needs a start-up pressure gradient.

The rule for the seepages of fluids in low permeability media deviate Darcy s Law in some extent.