Method for calculating thickness of each flowing layer of gas in unconventional reservoir dense rock pores

The invention relates to the field of unconventional oil and gas reservoirs, rock seepage mechanics and porous medium microflow, and discloses a method for calculating the thickness of each flowing layer of gas in dense rock pores of an unconventional reservoir. According to the method, the cross section of a pore in a compact rock matrix is regarded as a circle, the concept of virtual boundary is introduced, and gas flow is divided into a Darcy layer (a central region), a slippage layer (an inner ring region) and a Knudsen diffusion layer (an outer ring region) from a molecular collision mechanism; and then deriving an analytical expression of the thickness of each flowing layer by combining a Navier-Stokes equation, a reflection condition, effective viscosity and a molecular dynamics theory, thereby providing a method for calculating the thickness of each flowing layer of gas in the dense rock pores of the unconventional reservoir. According to the method, a new thought can be provided for research of perme