| Popis: |
Water injection into oil reservoirs is widely used practice to support oil production by maintaining the reservoir pressure within a desirable range to avoid a decline in reservoir pressure. Frequent monitoring of the water injectivity in the injection wells are very crucial to ensure meeting injection targets for an optimum level of reservoir management. Therefore, transient tests on water injection wells are an essential component in the data acquisition program of oil fields as these reveal important dynamic information about the wellbore condition and the reservoir characteristics. Usually, surface water is used for injection where the contrast in temperatures between the injected water (relatively colder) and the oil reservoir which is deep in the ground (hotter) creates a progressive colder-water bank inside the reservoir. Such a colder bank would have an effect on the injectivity of the well. Using traditional models without considering the thermal effect might result in underestimating or overestimating both reservoir flow capacity and skin damage. In this research, we will use a thermal model to study the pressure behavior during injection and falloff periods and observe the development of a colder-water front in which its size inside the reservoir will be investigated varying different parameters, such as duration of injection history, injection rate, and reservoir permeability. In addition, we will demonstrate the impact of the cold-water front on the injectivity. |
