Estimation Of Productivity Index Using Autocorrelation Technique Of Time Series Analysis Available to Purchase

Many techniques were provided for the evaluation of the productivity index of the producing wells. Most of these techniques use the information of the pressure buildup tests. This means that the process of productivity index estimation is accompanied by a shut - in period of the producer. This study provides a new approach based on one technique of those used for time series analysis. In the present work a simple idea about the dependence between the bottom hole flowing pressure and the production rate was developed through the well-known concepts of reservoir and production engineering. By using the dynamic change of both parameters auto correlation function is switched on to pick out the mutual independence of the two variables, which is, simply, the productivity index. The suggested method was conducted over two producing wells from the Gulf of Suez and the Western Desert. The estimated productivity index by the new approach does match that calculated through the buildup process. However, as the technique requires simultaneous mesurements of these two factors, it can be used wherever we have downhole multisensors. This situation encourages us to develop similar approach for replacing bottomhole flowing pressure by the wellhead pressure, through sensitivities to vertical flow correlations to simulate wells.