Topics of Reservoir Engineering.

Sort of topics that interested me so far are;
1. WOR interpretations.
I have collected two excellent papers so far as my references. The first one is “Analysis and Interpretation of Water-Oil-Ratio Performance ” V.V. Bondar, ChevronTexaco Corp., T.A. Blasingame, Texas A&M U. And the second one is “Variable-Rate Reservoir Limits Testing”
by T,A. Blasingame and W.J. Lee, Texas A&M U. I tried to validate the methods and applied it in my field. Several data needed and being very important i.e bottom hole pressure data versus time, oil/water rate versus time. In order to get precise result, all data above have to be clearly correct. The flow or pressure tests must be in steady condition and the metering devices must work properly. I didn’t make changes or revision on the methods, it’s just merely to try the methods in my field.
2. Three phase modeling of condensate banking phenomena.
I’m striving to get clear understand about the process of condensate banking.

Water InFlux

To forecast the performance in waterdrive reservoir, an aquifer model simulating the fluid flow in aquifer and that from aquifer into the reservoir is needed. Aquifer models may be classified based on flow regimes and flow geometries. In terms of flow regimes, aquifers may be grouped as pot model, steady state models, pseudo steady state models, and unsteady state models. Based on flow geometry, the aquifer-reservoir systems may be categorized as zero-dimensional,linear, and radial. The aquifer models considering radial flow geometry may additionally be sorted as edgewaterdrive or bottomwaterdrive. Aquifer models are commonly used in two different reservoir engineering applications; reserve estimate and reservoir simulation.

Water influx calculations are based on the geological and petrophysical parameters of the aquifer. Incorrect choices of aquifer parameters will result in deviation of the data from the straight line when F/E is plotted against We/E. Modifications of the aquifer parameters through a process of “aquifer fitting” can improve the match of observed pressure and production data with the reservoir characterization.

Water influx from very small aquifers can be calculated by time-independent material balance equations. However, for large reservoirs the aquifer boundary takes a finite time to respond to reservoir pressure changes and thus time dependent models such as developed by Hurst and van Everdingen, Fetkovitch, Carter and Tracy, or Allerd and Chen are used to calculate the water influx, We (Dake, 1994).

Reference : several sources