Volumetric Source Model to Predict Productivity of Fractured HorizontalWell in Naturally Fractured Reservoirs

To predict productivity of fractured horizontal wells with different completion methods, the flow models of reservoir and hydraulic fractures are developed by utilizing volumetric source idealization, while the models solved by taking orthogonal transformation. Compared to traditional point source functions, volumetric source function has many advantages in properties of function and programming calculation. A practical example of fractured horizontal well of open-hole and cased-hole is simulated, result shows flow rates of two cases have significant difference at early time, since benefit of production of horizontal well; but it also causes additional pressure, which has disadvantage in the productivity. The difference of productivity of fractured horizontal wells with different completion is decided by the interaction of horizontal well’s production and additional pressure drop, which has advantage and disadvantage in the open-hole case respectively. As a result, methods to cause additional pressure drop more seriously such as increasing number, length or conductivity of hydraulic fractures, would reduce the difference; methods to enhance horizontal well’s production such as better reservoir flow capacity, would raise the difference.