In order to be adapted to the development of the low-pressure drilling,aerate drilling technology was developed.It has advantages of high-capability of carrying cuttings,reducing the leakage,greatly improving the mechanical drilling speed,protecting low-pressure oil and gas reser-voir,and little formation damage,etc.Guo model and Beggs-Brill model which are gas-liquid two-phase flow theoretical models commonly used in aeration drilling of are compared to analyze the respective advantages and disadvantages.Based on the theory of multiphase flow and underbal-anced drilling and according to effect of cuttings on downhole negative pressure in the actual drill-ing process,Beggs-Brill model is modified to improve the calculation precision and rationality of the flow model by considering cuttings.What’s more,as an example,in this paper the calculation procedure in use of the field data is simulated,and the law of the flow in the shaft is analyzed to gives the reasons for the influence results.The results,compared with the measurement data, show that Beggs-Brill model is applicable.%欠平衡充气钻井技术是为了适应低压钻井的需要而发展起来的一项技术，具有携岩能力强、降低漏失、大幅度提高机械钻速和保护低压油气储层、地层损害小等优点。通过对比 Guo 模型和Beggs-Brill 模型2种充气钻井气液两相流的理论模型，分析了各自的优缺点。以多相流理论和欠平衡钻井基本原理为基础，根据实际钻井过程中岩屑对井底负压的影响，通过考虑岩屑来提高该流动模型的计算精度及合理性，对 Beggs-Brill 模型进行了改进。结合现场资料，应用 Beggs-Brill 模型对现场的充气钻井实例进行了模拟计算，分析了井筒流动规律，并对其变化情况进行了解释，将计算结果和现场实测结果对比分析，验证了模型的适用性。
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