A control system and method for determining optimal fluid injection pressure
is
based upon a model of a growing hydrofracture due to waterflood injection pressure.
This model is used to develop a control system optimizing the injection pressure
by using a prescribed injection goal coupled with the historical times, pressures,
and volume of injected fluid at a single well. In this control method, the historical
data is used to derive two major flow components: the transitional component, where
cumulative injection volume is scaled as the square root of time, and a steady-state
breakthrough component, which scales linearly with respect to time. These components
provide diagnostic information and allow for the prevention of rapid fracture growth
and associated massive water break through that is an important part of a successful
waterflood, thereby extending the life of both injection and associated production
wells in waterflood secondary oil recovery operations.
