Pressure Transient Analysis in Multiphase Multi Layer Reservoirs with Inter Layer Communication (SPE 152838)

The focus of this study is on the investigation of multiphase flow effects on the pressure transient analysis in layered reservoirs with cross flow. Virtually all studies on the subject of multiphase well test analysis have been carried out in a single layer reservoirs. However, many reservoirs are found to be composed of number of layers whose characteristics are different from each other and the wells in such reservoirs may be completed and produced from more than one layer. A novel technique is presented by replacing multi-phase multi-layer reservoirs with cross flow with an equivalent single phase single layer reservoir. In order to investigate the applicability of the presented method several reservoirs in which the contrast in phase saturations in each layer is the parameter of interest is considered. The reservoir parameters such as phase mobilities, skin factor and average reservoir pressure are compared with actual values. According to the results of this work, it has been concluded that the reservoir parameters can be estimated by high accuracy with equivalent single phase single layer reservoir however, the data should be interpreted with care if horizontal saturation gradient is significant in the layers.