摘要 |
<p>Apparatus for generating a pressure pulse in a fluid comprising a pipe, an opening into said pipe for filling said pipe with fluid, a piston mounted in the pipe, and coupled to a vibrator output. An air bleeder is mounted through said pipe at a location to remove all the air in the pipe as it is filled with fluid and vibrator control apparatus for controlling the frequency and phase of the vibrator and any additional vibrators coupled to a common fluid path.</p> |