Application and Study on Nonlinear Percolation Area Distribution Range Calculation Method in the Low Permeability Reservoir

Based on the minimum start-up pressure gradient have been obtained from experiment, and the relationship between the minimum starting pressure gradient with maximum starting pressure gradient and the throat radius, first put forward the calculating the limit shear stress, then calculating the maximum starting pressure gradient method. Non-linear seepage corresponding to the pressure gradient range are obtained by regression analysis, nonlinear seepage flow in low permeability reservoir distribution area can be derived. Two well group examples of the Bei301 block of Hailaer oilfield, shows that calculating the method of nonlinear seepage flow area is available, and the results can reflect the symmetry oil well production performance, this method has application value. The On the basis of the formula of pressure gradient between oil wells and injection wells, New method to calculate the limit injection production well spacing is proposed. It is of importance for injection production well spacing in oilfield development plan.