井下声波信号沿油管传输特性试验

Experimental study on transmission characteristics of downhole acoustic signals along tubing

针对试油测试中声波遥传技术的信号传输问题,研制了声波中继器试验样机,开展了声波沿管柱的传输特性试验研究。通过3口井的现场试验,探索了声波沿管柱的传输规律,结果表明,声波信号沿管柱的传输特性受井眼尺寸、油管长度以及套管内介质影响较大,声波信号强度随油管长度的增加呈指数衰减规律,本次试验条件下,最大传输距离为805 m;井内介质对声波信号的较优载波频率影响较大,当井内为空气时较优载波频段为10~10.5kHz,当井内充满水时较优载波频段为13~13.5 kHz。研究成果为声波遥传技术相关工具的开发提供数据支持,也为打破技术垄断,实现实时高效测试技术奠定基础。

For signal transmission in acoustic telemetry during well testing,a prototype acoustic repeater was developed,and an experimental study was conducted on the transmission characteristics of acoustic signals along tubing strings.Field experiments in three wells were carried out to explore the transmission patterns of acoustic signals along the tubing.The results show that the transmission characteristics of acoustic signals are significantly influenced by the wellbore dimensions,tubing length,and the medium inside the casing.The signal strength of acoustic waves decays exponentially with increasing tubing length,with a maximum transmission distance of 805 meters under the experimental conditions.The optimal carrier frequency of the acoustic signal is notably affected by the medium within the wellbore.When the wellbore is filled with air,the optimal carrier frequency range is 10~10.5 kHz;when filled with water,the optimal range shifts to 13~13.5 kHz.These findings provide valuable data for the development of tools related to acoustic telemetry technology,which lays a foundation for breaking technological monopolies and achieving real-time efficient testing.