气相井喷的泄漏源模型及其仿真

 钻井过程的井喷是气田开发中最严重的事故之一，研究气相井喷的泄漏和扩散进而为现场应急提供科学依据，必须首先明确钻井过程中井喷的泄漏源模型。采用流体力学特别是气体动力学理论与计算流体力学技术相结合的方法，分析和模拟了气相井喷的泄漏源模型。通过基于理论分析的数值仿真，得到了气相井喷的温度、静压和马赫数分布等气体动力学参数，仿真结果与理论分析以及相关实验的结论具有很好的一致性。研究表明，钻井过程中气相井喷的泄漏源可以用塞流模型表征，气相井喷可视为欠膨胀射流。

Study on Leakage Model of Gas Blowout and Its Numerical Simulation

Blowout is one of the most serious accidents of gas wells during drilling.To investigate leakage and dispersion of gas blowout and to provide scientific guidance for on-site emergency response,it is necessary to identify what model should be used to describe the leakage source.Leakage source model of gas blowout was theoretically analyzed by fluid dynamics and aerodynamics,and was also numerically demonstrated by computational fluid dynamics.Distributions of temperature,static pressure and Mach number were obtained from simulation based on theoretical analysis.These numerical results agree well with both theoretical results and related experimental results done by other researchers.The present study shows that leakage source of gas blowout during drilling stage can be characterized by model of choked flow and gas blowout can be recognized as under-expanded jet flow.