Numerical Simulation On Water Coning Of The Fractured Reservoir With Bottom Water

Water coning has been a complex phenomenon observed in conventional and non-conventional reservoirs,it has been a serious problem encountered in active bottom water drive reservoirs.The water coning phenomenon in a naturally fractured reservoir has a lot of uncertainties,for better understanding of these reservoirs an effective evaluation,prediction and planning of these reservoirs requires an early recognition of role of natural fractures(fluid flow channels),the role of the matrix which acts as storage mediums.With much consideration of these uncertainties came the reason behind this research.The purpose of this research is to address water coning issues by simulation of controllable and uncontrollable reservoir parameters that affect water coning phenomenon in a naturally fractured Oil Reservoir with bottom water.In this work a numerical simulation software eclipse E-100 black oil simulator will be used to develop a model(dual porosity dual permeability model)with a single well radial cross section with a bottom water aquifer.Water cut(WCT)Oil production rate(OPR),and Oil production total(OPT)will be used to evaluate coning phenomenon in a naturally fractured reservoir,In the course of the study sensitivity analyses on the modeled reservoir's Production rate Q,Anisotropy ratio k_v/k_h Fracture Permeability k_f,Fracture spacing,wettability,Mobility ratio M,Storativity capacity?,Oil layer thickness h,Radial size Re,Perforation thickness and standoff from WOC,and Aquifer volume were conducted to evaluate their effect on coning behavior in fractured reservoir..The height of water cone will be checked based on some Parameters that enhance water coning.The results obtained depict that increase in anisotropy ratio resulted to increase in water cut while decrease resulted to decrease in water cut,Increase in production rate resulted to increase in water cut while a production rate of 50stb/d which is about critical flow rate did not form cone,increase in vertical fracture permeability resulted to increase in water cut because water travels fast in vertical direction,while increase in horizontal fracture permeability resulted to high oil production due to better distribution of fluid on horizontal plane,Increase in storativity capacity resulted to increase in water cut,while decrease in storativity capacity resulted to low water cut.Fracture spacing has little effect on water cut,Oil viscosity showed that heavy oil and light oil resulted to low water cut while a medium viscosity oil resulted in high water cut,increase in oil layer thickness resulted to low water cut while a thin oil reservoir resulted to high water cut Increase in perforation interval resulted to an increase in water cut,the closer the perforation interval is to WOC the higher the water cut,Increase in radial size of the reservoir resulted to low water cut,while a small radial size resulted to high water cut,Aquifer volume affects water coning,increase in aquifer volume lead to early breakthrough time,high water cut and abrupt growth in cone height,while a small aquifer delayed breakthrough time,resulted to low water cut and cone formation was slow.