This work presents a computational study to understand different heat transfer and phase transition processes of two-phase flow in a geothermal wellbore. The simulation uses a six-equation model with mass, momentum, and energy balance equations for the liquid and vapour phase, which is available in Ansys Fluent. The model considers the effect of phase transition due to flashing, caused by thermal non-equilibrium at the liquid-vapour interface. Two wellbore scenarios, one with a constant inner diameter and the other a variable inner diameter along the flow direction due to calcite scaling, were simulated using the model. Comparison of the simulation results with measured pressure log data shows good agreement. Simulation studies for the fluid flow in a wellbore with variable diameter occurring due to calcite scaling shows higher mass transfer rate and wall normal bubble flux in the region of scaling, resulting in higher chances of mineral precipitation and deposition in the same region.

这项工作提出了一项计算研究，以了解地热井筒中两相流的不同传热和相变过程。仿真使用六方程模型，其中包含液相和气相的质量、动量和能量平衡方程，Ansys Fluent 中提供了该模型。该模型考虑了由闪蒸引起的相变影响，这是由液-汽界面处的热非平衡引起的。使用该模型模拟了两种井筒情景，一种具有恒定内径，另一种具有沿流动方向由于方解石结垢而变化的内径。模拟结果与测得的压力测井数据的比较显示出良好的一致性。