Implosion test method for underwater hollow structures

By compressing air above water in a pressure tank, a photo multiplies tube underwater implosion test was conducted at 0.5 MPa hydrostatic pressure. The pressure tank was made of steel with its diameter of 3 m and its length of 5 m, and its inner wall was stuck with a layer of low acoustic impedance rubber material to reduce effectively the influences of the reflection shock wave at the inner wall surface on the implosion test results. By providing high-power lighting through the PMMA window of the pressure tank, a high-speed camera recorded the implosion test process clearly. It was shown that the pressure curve in time domain of shock wave in the underwater implosion test agrees well with that of theoretical study. The study results provided a good implosion test method for underwater hollow structures.