Classification Study on Relative Permeability Curves

The classification method of relative permeability curves is rarely reported, when relative permeability curves are applied; if the multiple relative permeability curves are normalized directly, but not classified, the calculated result maybe cause a large error. For example, the relationship curve between oil displacement efficiency and water cut, which derived from the relative permeability curve in LD oilfield is uncertain in the shape of low water cut stage. If being directly normalized, the result of the interpretation of the water flooded zone is very high. In this study, two problems were solved: 1) The mathematical equation of the relationship between oil displacement efficiency and water cut was deduced, and repaired the lost data of oil displacement efficiency and water cut curve, which solve the problem of uncertain curve shape. After analysis, the reason why the curve is not available is that relative permeability curves are not classified and optimized; 2) Two kinds of classification and evaluation methods of relative permeability curve were put forward, the direct evaluation method and the analogy method; it can get the typical relative permeability curve by identifying abnormal curve.