Thermal-Hydrodynamic Modeling Includes Fracture-Flow Analysis To Assess Well Flow

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTeC 4054832, “Horizontal Well-Flow-Profile Assessment: Advanced Thermal-Hydrodynamic Modeling With Fracture-Flow Analysis,” by Maxim Volkov, Yulia Fesina, SPE, and Natalya Kudryavaya, TGT Diagnostics, et al. The paper has not been peer reviewed. _ Production logging in horizontal wells plays a critical role in the strategic development of hydrocarbon fields. However, conventional diagnostic methods for reservoir evaluation often face challenges in interpreting well performance accurately because of complex flow patterns. The complete paper discusses the concept, applications, and continual evolution of a new 3D temperature and spectral acoustics modeling and logging approach. This methodology has undergone rigorous testing across diverse field trials, encompassing a variety of completion designs, logging conditions, and operational types, that have validated the effectiveness of the modeling approach and illuminated its potential. Theoretical Background and Modeling This section of the complete paper provides a comprehensive overview of a recently developed thermophysical model designed for the quantitative interpretation of temperature and pressure-logging data in horizontal wells. The model accurately details the dynamics of fluid flow and heat-transfer phenomena within a well with multiple fractures and drilled in an anisotropic reservoir. It describes complex interactions between the wellbore, surrounding geological structures, and fluid dynamics, thereby facilitating a deeper understanding of the reservoir’s behavior under various operational conditions. This advanced modeling approach enables more-precise predictions and improved decision-making in the management and exploitation of hydrocarbon resources. The complete paper details the theoretical foundations of the model, including equations related to the modeling of hydrodynamics and conjugate heat transfer. To enhance the understanding of downhole temperatures and reduce uncertainties in interpreting temperature anomalies, temperature logging typically is conducted alongside passive spectral acoustic tools. Measuring acoustic fields while flowing the well allows for the classification of the flow type at each measurement point within a 10- to 15-ft scanning radius. This approach helps identify turbulence (acoustic noise) from flow in the matrix, fractures, and their initiation points, and annular flow between the casing and liner and the sand interface, including cases of completion-integrity failure. Although modeling temperature is feasible without spectral acoustics, using hydrophones significantly aids in deciphering indicated temperature anomalies, detecting minor flow zones that may not produce temperature anomalies. Spectral acoustic data acquisition covers the same intervals as temperature logging but generally is performed during the upward pass at stations spaced proportionally to the number of tools used, with vertical resolution parameters set before the operation. Recent advancements have enabled a vertical resolution of 1 ft and the capability to assess the radial distance to the acoustic source. Temperature data are collected primarily during a continuous down pass at a speed of 15–20 ft/min. To calibrate the Cascade 3D model, it is advisable to use at least two different well operational regimes: shut-in and either flowing or injection. Two case studies are included in the complete paper to show the application of the described modeling in the horizontal producer and injectors, its ability to assess the temperature response in different well configurations such as openhole and smart completions, and its potential to identify and quantify the flow from the areas that are supposed to be isolated. Both surveys were conducted using coiled tubing methods under at least two logging regimes: shut in and flowing. The first case study is included in this synopsis.