Abstract

A one dimensional, three-phase cylindrical reservoir simulator was used to investigate Inflow Performance Relationship curves for two-phase flow conditions, with or without skin around the well-bore. Vogel-type plots are used for plotting the data from the simulator. Using regression analysis, a new equation has been developed to calculate the present IPR curve with or without skin.

The investigation was continued to develop a new equation for predicting future IPR curve, based on production and pressure test data which are taken at present. The equation was developed based on the relationship between k_ro/u_OB_O vs pressure obtained from the simulator.

Those two equations are applied to several wells in Sangatta Field (Pertamina UEP-IV) and Tanjung Miring Timur (Pertamina UEP-II). Flow After Flow test data, from TMT-27, are used to construct the IPR curve based on Fetkovich's and the proposed IPR curve equation. Both curves show good agreement.

Pressure and production test data from ST-64 and ST-98 are used for calculating IPR curves, using the proposed IPR curve equation and the extension of Vogel's equation by Standing. The results show that for positive and negative skin factor the proposed equation gives better results.

Flow After Flow test data from TMT-11 show a turbulent condition occurs in the wellbore during the test. If the test data are applied to the proposed equation, the resulting predicted IPR curve is higher than the Fetkovich's IPR curve. This can be understood since the proposed equation was developed with the assumption that turbulent conditions do not occur in the wellbore.

The proposed equation for predicting IPR curve is compared to Fetkovich's equation, using the data from TMT-27. The result shows very good agreement.