Wellbore leakage of carbon dioxide (CO₂) injected into storage zones can induce significant temperature anomalies. These thermal signals arise from expansion of the leaking CO₂ associated with the pressure drop across the leak, known as the Joule-Thomson effect, which has the potential to reveal the nature of leakage and determine the wellbore leakage rate of CO₂. We investigate the strength of the temperature signal as a function of leakage rate and develop a control volume analysis to relate these two in the complex two-phase leakage conditions. This analytical thermal model for CO₂ leakage enables quick analysis with sufficient accuracy to estimate the leakage rate. The application range of this approach is identified from the results of comprehensive investigations. The nature of the thermal signal is sensitive to the balance between the Joule-Thomson effect and heat conduction. The ratio of these two effects and newly defined JT/cond Number provide general criteria for the applicability of modeling these thermal signals in the range of 40–90% and 1.6-4, respectively. Furthermore, in the case of higher leakage rate, we extend the analytical model to predict the leakage transmissibility with improved accuracy compared to the direct rate estimation from leakage thermal model in this scenario. The general procedure and flow chart to apply the proposed approach to a practical problem are provided, which is suitable for both injection and post-injection periods for a CO₂ storage project. This analytical model breaks a new ground to apply recent temperature wellbore monitoring developments for CO₂ leakage detection and characterization purposes. Field applications of this model can complement other leakage rate estimation techniques and be an essential part of the CO₂ leakage detection tool if other approaches are not viable.

注入存储区的二氧化碳（CO ₂）的井眼泄漏会引起明显的温度异常。这些热信号是由泄漏的CO _2的膨胀引起的，该膨胀与穿过泄漏的压降相关联，称为焦耳-汤姆森效应，它有可能揭示泄漏的性质并确定井眼的CO ₂泄漏率。我们研究温度信号的强度与泄漏率的关系，并进行控制量分析以在复杂的两相泄漏条件下将这两者联系起来。此CO ₂分析热模型泄漏能够以足够的准确性进行快速分析，以估计泄漏率。这种方法的应用范围是从综合调查的结果中确定的。热信号的性质对焦耳-汤姆逊效应和热传导之间的平衡敏感。这两种效应的比率以及新定义的JT / cond数分别为在40-90％和1.6-4范围内对这些热信号进行建模的适用性提供了通用标准。此外，在较高泄漏率的情况下，与这种情况下的泄漏热模型的直接速率估算相比，我们扩展了分析模型以提高泄漏预测的准确性。提供了将建议的方法应用于实际问题的一般过程和流程图，_2个存储项目。该分析模型为将最新的温度井眼监测开发应用到CO ₂泄漏检测和特征分析中开辟了新的天地。如果其他方法不可行，该模型的现场应用可以补充其他泄漏率估算技术，并且是CO ₂泄漏检测工具的重要组成部分。