Lamb波在石油勘探中的应用研究实验

Applied research experiment of oil exploration using Lamb wave

用频率为342 kHz的Lamb波检测水基钻井液的含气情况.实验结果表明:发射、接收传感器之间在重叠-100.0^-56.0 mm时,可接收到理想的信号;声速随含气量的增加变化很小,最大变化约为9 m/s,不易用声速来检测钻井液中的含气量;而声透射损失随含气量的增加急剧增大,在气泡大小、分布一定的条件下,可以用声透射损失来反映水基钻井液中的含气量.

The concentration of entrained air in water-based drilling fluid is inspected by 342 kHz Lamb wave. The experiment results indicated that ideal signal appeared at a superposed distance of -100.0--56.0 mm between the emission and receiver transducer. The velocity of sound doesn＇t change obviously with increasing entrained air concentration. The largest change is roughly 9 m/s. Therefore, the ultrasonic velocity is unsuitable to inspect the concentration of entrained air. But the transmission loss is very sensitive to the increase of the concentration of entrained air. Given the natural condition of the size and distribution of bubbles, the concentration of entrained air might be inspected by using the sound transmission loss.