As is well known, fields containing great amount of condensate in gas phase are comparable to oil fields. Phase transformations of formation fluid makes the main influence on the oil, gas and condensate field development process, and consequently on condensate and oil recovery. The paper focuses on solution to one of the problems encountered in history matching process of oil, gas and condensate reservoir with oil rim concerning quantitative description of the multiphase fluid.
Along with complex fluid model, varying formation fluid composition with depth, transforming from gaseous phase into liquid phase, high amount of condensate in formation gas, geological framework etc., relative permeability curves are an overriding concern in modelling of gas displacement from oil rim and oil displacement from gas saturated formations.
On the basis of the history matching results in general and the maximum possible oil, gas and condensate rate matching, every well was analyzed individually. History matching was achieved by matching oil rate in wells producing from oil rim, partially gas, and by matching gas rate in wells producing from gas-saturated units.
The main challenge of history matching process was misfit between simulated parameters of gas wells, in particular C5+ fractions because of incorrect distribution of gas saturation and modelling of C5+ fractions as an oil phase. In the model with increase of gas production, the C5+ production increased as well, while according to historical data condensate-gas ratio was decreasing.
The shapes of gas-oil relative permeability curves without changing their critical parameters were adapted while history matching of gas ratio (in oil wells) and condensate-gas ratio (in gas wells).
That is one possible way of history matching of simulated model of a complex oil, gas and condensate field with an oil rim.
As a result of comprehensive efforts, including the adaptation of relative permeability curves, the simulated model was history matched within 3% error in oil production and less than 1% error in gas production.