钻井液连续脉冲信号频域传输速度影响因素

Influence factor of transmission velocity in frequency domain of drilling-fluid consecutive pulse signal

随钻测量过程中,有效提高脉冲信号的传输速度能减少信号延迟时间,提高信号传输精度。根据连续脉冲信号传输频域模型,对影响信号传输速度的钻井液组分含量特性、钻井液水力摩擦系数以及脉冲信号频率等参数进行了计算分析。结果表明:随着钻井液密度及压缩性的提高,信号的频域传输速度降低,钻井液的含气量对速度的影响更为显著;信号传输速度随脉冲信号频率的增加而增加,并存在稳定传输频率值;钻井液水力摩擦系数越大,信号传输速度越小,而信号稳定传输频率越大。

During measurement while drilling, the increase of transmission velocity of pulse can reduce the signal delay and raise the transmission precision. According to the model of transmission velocity of consecutive pulse in frequency domain, the effects of the content of drilling fluid component, hydraulic friction coefficient of drilling fluid and frequency of consecutive pulse on the pulse transmission velocity were analyzed. The results show that the transmission velocity of pulse decreases and the influence of free-gas content of drilling fluid is much more remarkable with the density and compressibility of drilling fluid increasing. The transmission velocity increases with the pulse frequency increasing and there is a stable transmission frequency for drilling fluid system. The transmission velocity decreases and the stable transmission frequency of pulse increases with the hydraulic friction coefficient of the drilling fluid increasing.