Thermal transients during nonisothermal fluidj injection into oil reservoirs

摘要

During hot fluid injection into oil reservoirs,the importance of determining the temperture profile to estimate the thermal efficiency is well known.In addition,the resultant temperature distribution due to cold water injection into a hot reservoir during waterflooding may significnatly ineluence the stress distribution in the reservoir.Owig to these facts,in thisj work we present a new two-dimensional analytical model for analyzing the thermal transients during nonisothermal fluidj injections into oil reservoirs that may provide a better insight into the mechanism of heat transfer in oil reservoirs.The new modle has several distinguishing aspects.Primarily,it isj the first analyticla solution of an unsteady state two-dimensiional het transport process in a laterally/vertically confined layer.In addition,both finite lonitudinal and transverse heat disperiosn have been accounted for in the modle as well as the heat loss to the bounding layers.Thus,the model allows one to observe the roles of both boundary conditions and fluid mechanics controls simultaneously,a feature not possessed by dispersion concept has also been incorporated in teh new model in order to acocunt for th emuch lrger temperature transition zones observed in the fieldj than that would be caused by pure conduction.Finally,since the solution is free of numerical dispersion and nonphysical oscillations,especially in two-dimensional domains,it serves as a higher stepping stone for validaiton of numericla models.