The numerical simulation of horizontal well bow missing characteristic wave

摘要

There may exist the bow missing at the top of the cement ring, the eccentric sound source and other complex situations in horizontal wells. It is better to build models of different height of bow missing, the eccentric sound source and so on. To achieve the numerical simulation of bow missing well sound field in horizontal wells, we often use the staggered - grid finite method to solve partial differential order equations of the stress - velocity. The results show that bow missing affects the amplitude of the first wave and the travel time of the sound field. We have collated the sound field of vertical well II interface channel. It is considered that the first wave is typical of II interface wave when the bow height is less than 30mm. The sound field of bow missing with the eccentric source is similar to that of II interface ring missing. Its characteristic wave amplitude and travel time are affected by the eccentricity. Finally, the receivers arranged around the borehole wall can determine the missing orientation.