Abstract: Low permeability gas reservoir is normally charaoterized by low porosity, low permeability and high water saturation, and the existence of slippage efect is obviously found in gas flowing through porous media without ireducible water. The tighter the roek, the lower the permeability, and the more obvious the slippage efeet is. However, common gas reservoir model is never the less used for numerical simulation study of low-permeability gas reservoir, which leads to more differences between development indices predicted and real ones. The mechanism of percolation in low-permeability gas reservoir is analyzed. The nonlinear percolation mathematic model to both gas and water is then developed. Furthermore, the related numerical and simulation mnodels and simulator are established, considering the concept of gas relative permeability with the slippage effect.

Key words: low-pebhlly gea reservoir, slippage effect, relative permeability, two-phase flow, simulator