It is desirable to introduce heat into the production system of a horizontal well and the adjacent heavy oil reservoir. An increase in temperature can remove thermally alterable skin effects, which inhibit production, decrease oil viscosity to increase the productive length of the well, improve pumping efficiency, and reduce the energy requirements to lift the oil to surface. One way to create the heat is to use electricity.; The objective of this thesis is to solve the heat transfer problem for a horizontal well producing from a heavy oil reservoir where both the wellbore and reservoir are heated using low frequency electromagnetic energy. A semi-analytic model is thus developed that can be used to estimate the temperature distribution along the length of the horizontal well.; The problem consists of simultaneously solving for the effects of several concurrent heat transfer mechanisms occurring in different regions of the wellbore and reservoir. Electrical current flowing in the reservoir produces heat there because of the resistance of the reservoir. Significant heat is also generated as current flows in the horizontal well as a result of hysteresis and eddy current losses. As well, heat is produced from the reservoir with the fluids that flow into the wellbore and heat is conducted away from the well by thermal conduction. Thus, the heat transfer problem has to account for linear and non-linear electrical heat sources in several regions and heat transfer by thermal conduction and convection.; The horizontal well is constructed from commercial grade carbon steel pipe which is an electrically conducting ferromagnetic material. The hysteresis and eddy current losses in the steel pipe are determined using a finite difference time domain solution of Maxwell's equations. This numerical model, herein called the EM Pipe Loss model, is programmed to account for the non-linear magnetization process of the material using hysteresis loops. The hysteresis and eddy current losses in the pipe are calculated for a range of current values. A general polynomial is then fit to the calculated data so that the electrical losses can be interpolated for any value of current. The numerically derived polynomial is then incorporated into the equations that describe the heat transfer problem, for which an analytic solution is then obtained.; It was found that for a long horizontal well, heat transfer to the adjacent reservoir by thermal conduction from the heated wellbore has a greater effect on the temperature achieved in the reservoir than heat transfer by convection and electrical heating by current flow in the reservoir. Also, it is shown that hysteresis and eddy current losses in the steel pipe cannot be ignored as was done previously (1), (2), and (3). For a given current, hysteresis effects can more than triple the total power losses in the horizontal wellbore and other sections of the production system when compared to the power losses that would be present if hysteresis effects are ignored. This limits the magnitude and extent of electrical heating in the reservoir adjacent to the wellbore that can be achieved. The results obtained show that a significant volume of the reservoir and length of the horizontal well can be heated, which can substantially contribute to enhanced production rates from the reservoir.
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