Abstract
The influence of hydraulic fractures during production is to alter the wellbore/sandface temperature changes by reducing the magnitude of the Joule-Thomson expansion effect. Compared to an unfraced completion in which the flow path of the reservoir fluids is purely radial, the presence of hydraulic fractures lengthens the flow path the reservoir fluids must take by creating a linear flow geometry. For a given drawdown, therefore, the local pressure gradients are lower in a hydraulically fractured completion compared to a non-hydraulically fractured completion. Through dimensionless analysis it will be shown that the Joule-Thomson effect is proportional to the local pressure gradient squared which implies a reduction in the Joule-Thomson effect for a hydraulically fractured completion compared to a non-hydraulically fractured completion. Simulations from a thermal reservoir/wellbore model will be presented comparing the thermal responses between hydraulically fractured and non-hydraulically fractured completions. It will be shown that the presence of hydraulic fractures can reduce the wellbore/sandface temperature changes by much as 85% compared to a non-hydraulically fractured completion. Additionally it will be shown that measurement of sandface and wellbore temperatures during production can provide information to determine which intervals have been successfully hydraulically fractured, and to a lesser extent a qualitative assessment of hydraulic fracture efficiency.