超声波在钻井液中传播衰减理论研究

Research of ultrasonic attenuation theory in drilling fluid

刘飞 付建红 张智 许亮斌

LIU Fei FU Jianhong ZHANG Zhi XU Liangbin

西南石油大学·油气藏地质及开发工程国家重点实验室，四川成都　610500 中石化石油工程技术研究院，北京　100101 中海石油研究总院，北京　100027

State Key Laboratory for Oil and Gas Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China Research Institute of Petroleum Engineering, SINOPEC, Beijing 100101, China

超声波流量计是现阶段精度最高、通用性好、灵敏度最高的流量计，但由于超声波在钻井液中衰减很大，使其未能测出钻井液的环空返出流量。通过Urick模型研究了超声波流量计在测量钻井液流量中超声波的衰减规律，分析了传播距离、超声波频率、液体密度等因素对超声波衰减的影响。通过研究得出钻井液中固相颗粒的数量每增加1个数量级，超声波能量衰减也增加一个数量级，超声波能量衰减随钻井液中固相颗粒直径、钻井液密度、传播距离的增加而增大，超声波频率越大，超声波能量衰减越快。该研究结果为超声波在钻井液测量中的进一步应用提供了理论基础。

At present, the return of drilling mud is measured by target type meter, but the result is not very accurate because of environment. The ultrasonic flowmeter is the most accurate, normal and sensitive apparatus, but the return flow of drilling mud can not be measured by ultrasonic flowmeter because of the huge ultrasonic attenuation in drilling fluid. The ultrasonic attenuation law was researched with the Urick Model when the flow of drilling fluid was measured by ultrasonic flowmeter. The effects of the factors on ultrasonic attenuation were analyzed, such as ultrasonic propagation distance, frequency, and liquid density..It was concluded that the ultrasonic attenuation would increase by one order of magnitude with the increase of the quantity of solid-phase pellet in the drilling fluid by one order of magnitude, and the ultrasonic attenuation increased with the increase of the diameter of solid-phase particles in the drilling fluid, the drilling fluid density and the propogation distance. The larger ultrasonic frequency is, the quicker ultrasonic attenuation is.