Home – Home – Jornals – Russian Geology and Geophysics 2026 number 9

This paper presents the development and experimental validation of an active thermometry method for quantitatively assessing the fluid flow rate in horizontal wells. Two approaches are investigated in experiments on a physical well model under single-phase flow conditions: the calorimetric method, based on the integral superheat of a homogenized flow, and the convective method, which relies on the relationship between the heated pipe wall temperature and the flow rate. The Richardson number (Ri) is identified as the key criterion governing the heat transfer mechanism. For Ri > 1 (low flow rate), thermogravitational effects dominate, leading to significant thermal stratification of the flow. Under such conditions, the calorimetric method proves more reliable and enables flow rate determination with high accuracy (a deviation of ≤ 10%). The limitations of the convective method are also identified. In this study, the interpretation of the convective method considers only the forced convection component (Dittus-Boelter model). This method is valid only for Ri < 0.1 (high flow rates). This work provides a methodological foundation for further development of the method, with key directions including the refinement of the convective model to account for free (natural) convection and the adaptation of both approaches to multiphase flow conditions.