Application of active thermometry technology in the determination of the behind-the-casing flow into upper aquifer

Based on the results of numerical mathematical modeling, the application of active thermometry technology to determine of the behind-the-casing flow into upper aquifer is considered. The technology of active thermometry be confined in local induction heating of a section of a metal casing in a well, recording the temperature of the inner wall of the casing at the heating site, as well as above and below it. Mathematical modeling is based on the numerical solution of the Navier-Stokes equations and heat transfer equations, taking into account convection, thermal conductivity and a heat source in the Ansys Fluent software package. Two variants are modeled, in the first variant there is gas in the well in the logged section, in the second – water, which corresponds to a different position of the fluid level in the well relative to the logged section. The criteria are shown to determine the presence of the behind-the-casing flow on a series of surveys of the casing temperature distribution in depth: the asymmetry of the casing temperature distribution curves in depth relative to the middle of the heating section, the movement of the maximum point on the temperature curves in time upward in the direction of the behind-the-casing flow. It is shown that the results of surveys the temperature of the casing wall (in depth, in time) can be used to quantify the flow rate of the behind-the-casing flow. Keywords: active thermometry; temperature field; induction heating; aquifer; ecological monitoring; behind-the-casing flow.