气体循环钻井室内相似模拟方法研究

The research on indoor simulation method of gas circulation drilling in a similar way

武乾文 柳贡慧 李军

WU Qianwen LIU Gonghui LI Jun

中国石油大学，北京　102249 北京联合大学，北京　100010

China University of Petroleum, Beijing 102249, China Beijing Union University, Beijing 100010, China

气体循环钻井是一种新的工艺方式，与常规气体钻井存在不同之处。当气体钻井转变为气体循环钻井时，井内的压力、流速会发生变化，进而对携岩产生影响。因此，针对气体循环钻井的室内相似模拟的研究具有重要的工程意义。在相似理论的基础上，以管流内压力的变化规律为研究对象，对气体循环钻井室内模拟方法进行了研究。研究的3种模拟方法分别为动力相似模拟、雷诺数相似模拟、欧拉相似模拟。其中，动力相似模拟适用于对关键点的模拟，雷诺数相似模拟适用于对整体过程的模拟，欧拉数相似模拟适用于对部分井段的模拟。通过不同模拟条件下的模拟数据对比，验证了3种模拟方法的可行性，为气体循环钻井室内相似模拟奠定了理论基础。

Gas circle drilling is a new drilling technology, which is difference from conventional gas drilling. When gas drilling is transformed into the cyclic form, the pressure and gas velocity in the bore hole will be changed, as a result the carring capacity of the rock will be influenced. So it is of great significance to carry out simulation research on the gas circle drilling in the lab. Based on the similarity theory, taking the pressure variation regulalarity as the research target, three simulation methods of gas circle drilling are studied in the lab, i.e. the similar dynamic simulation that is applicable to the simulation of key points, the similar Reynold’s mumber simulation that is applicable to the simulation of the whole process, and the similar Euler number simulation that is applicable to the simulation of some hole sections. They are proved to be feasible as the results of the related simulation coincide with the theory, providing theoretical basis for the lab simulation of gas circle drilling.