Heat Transfer During Hot Fluid Injection Into an Oil Reservoir

Abstract

The engineering el'aluation of thermal reCOl'ery proc- esses depends on tlie ability to predict their behal"iour in the field. Such a prediction, whether based on physical or mathematical models. requires an accurate accounting of the thermal energy utilized by the process. This paper presents a critical rel'iew of th.e important contributions to the literature concerning heat transfer during hot fluid injection into an oil reservoir. The heat transfer mechanisms, the resulting energy balance equation and the restrictive assumptions necessary to obtain analytical solutions of the energy balance equation are discussed. These solutions yield information relatil'e to the thermal efficiency of the process and the temperature distribu- tions within the reservoir and the surrounding imperme- able media. However, to date, the published techniques have been limited to injection into a linear or radial homo- geneous sand with constant physical properties and have not considered multidimensional heat transfer completely. 'Ve hal'e applied a recently published numerical tech- nique to the sol.ution of the energy balance equation in order to remOVe these limitations. The accuracy of the numerical method for the case of one-dimensional fluid flow is demonstrated in the paper by comparing the cal- culated thermal efficiency for hot water injection into a water sand to the corresponding analytical solution. A comparison with published experimental results demon- strates the utility of the method and confirms our un~ derstanding and analysis of the heat transfer mechan- isms.