A Method for Identifying Interwell Connectivity and Predicting Oil-Water Performance

Abstract

The invention provides a method for recognizing inter-well connectivity and predicating the oil-water dynamic state. The method comprises the steps that a water drive oil deposit inter-well connectivity evaluation model considering two phases of oil and water is built; a water drive oil deposit oil saturation tracing equation for the two phases of the oil and the water is built; the effective control volume of a single well is calculated through a Koval method; initial values of a connectivity factor, a interference factor and a time constant are given; then, the average oil saturation and liquid production capacity of a jth oil well within a first time step are obtained according to the model and the equation; and the oil saturation of the oil-water front is solved; a minimized objective function is built according to injection and output data of an oil-water well, the objective function is subjected to minimized calculation through a constrained optimization algorithm, and the optimal connectivity factor, the interference factor, the time constant and the average oil saturation are obtained; and the connectivity relationship between injection and production wells is discriminated according to the optimal connectivity factor, and predication of dynamic indicators is conducted according to a model after update.

Description

technical field [0001] The invention relates to a method for identifying connectivity between wells and predicting oil-water dynamics, in particular to a method for combining stratum and fluid attribute data with injection-production dynamic data, and performing inversion of related parameters with the help of an optimization algorithm to identify the connectivity and dynamics of oil-water wells. A new method for oil-water dynamic prediction belongs to the technical field of oil and gas development. Background technique [0002] At present, most old oilfields in my country have entered the middle and late stages of development. The underground seepage is complicated, the water injection efficiency is not high, and serious problems such as channeling of injected water often occur, which leads to a rapid increase in water cut during oil well production and difficult ultimate recovery. improve. The research on inter-well connectivity of oil reservoirs is the basis of fine water...

AI Technical Summary

Problems solved by technology

[0020] The above existing methods are more difficult to implement, costly, and have a long cycle

For thin layers, the distribution of oil layers, water layers and oil-water layers are intertwined and complex, it is difficult to determine the connectivity of formations by horizontal correlation between wells and logging data, and it is difficult to ensure the correctness of the correlation;

[0021] The implementation of pressure test, tracer test and well test will affect the normal production of the oil field, and it is expensive;

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