Fateme Mehran - Mazandaran University, Faculty of Chemical Engineering
Kamyar Movagharnejad - Mazandaran University, Faculty of Chemical Engineering
Ali Didanloo - Iranian Society of Petroleum Engineers

Reservoir fluid properties are very important in reservoir engineering computations such as material balance calculations, well test analysis, reserve estimates, and numerical reservoir simulations. Ideally, these properties should be obtained from actual measurements. Quite often, however, these measurements are either not available, or very costly to obtain. In such cases, empirically derived correlations are used to predict the needed properties. All computations, therefore, will depend on the accuracy of the correlations used for predicting the fluid properties. Two nonlinear multiple regression analysis models for predicting the formation volume factor at the bubble point pressure and reservoir bubble point pressure are developed during this study. This study is developed using 387 published data from more than 40 Iranian oil fields. This data includes reservoir temperature, Gas Oil Ratio (GOR), gas gravity ,oil gravity ,formation volume factor(Bob) and bubble point pressure(Pb) that was obtained from PVT laboratory. The results show that the developed model provides better predictions and higher accuracy than the published empirical correlations. The present model provides predictions of the formation volume factor at the bubble point pressure and for reservoir bubble point pressure with an absolute average percent error of 1.7% and 9.3% a standard deviation of 2.84% and 28.3% and correlation coefficient of 0.964 and 0.895 respectively.

Iranian Oil Fields, Oil Formation Volume Factor, Bubble Point Pressure, New Correlation Corresponding