MODEL EXPERIMENTS ON THE ACOUSTIC SIGNAL FROM AIRDROPPED MINES
Abstract
Model experiments were undertaken to determine the origin of the acoustic pulse which occur after the pulse at impact. The experiments were designed primarily to distinguish between cavity closure and wall slap (due to whip) as possible sources of the acoustic signal. The projectiles used were 1- in.-diam model of the Mk 36 mine. Experimental evidence is presented which supports the following conclusions concerning acoustic signals from air-dropped mines: (1) The first signal is due to the nose entering the water. (2) Subsequent signals are produced by the tail touching the water (in the case of oblique entry) and by the slap of the tail of the mine case against the cavity wall. (3) Closure of the cavity does not produce a comparable signal, at least above 100. (4) The acoustic intensity is more dependent on the details of the impact than upon velocity. (5) Most, and perhaps all, of the acoustic signal is due to shock-excited vibrations of the mine case which are transmitted to the water.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1952
- Accession Number
- AD0006201
Entities
People
- Francis E. Fox
- Joseph L. Hunter
- Robert L. Meister
- Walter C. Connolly
Organizations
- The Catholic University of America