Accession Number:

AD0643549

Title:

A STUDY OF THE BULK CAVITATION CAUSED BY UNDERWATER EXPLOSIONS

Descriptive Note:

Research and development rept.

Corporate Author:

DAVID TAYLOR MODEL BASIN PORTSMOUTH VA UNDERWATER EXPLOSIONS RESEARCH DIV

Personal Author(s):

Report Date:

1966-09-01

Pagination or Media Count:

172.0

Abstract:

The detailed theoretical models of bulk cavitation and bulk cavitation data obtained from tests are used to develop simple calculations for predicting bulk cavitation phenomena. Several reasonable mathematical approximations describing these phenomena are derived. The mathematical treatments have, as a foundation, concepts derived in the theoretical study however they are modified and simplified where experimental results indicate that such modifications and simplifications are justified. With these approximate mathematical models, estimations can be made of the boundaries, depths and durations of cavitation as well as the motion of the water surface for a wide variety of conditions without employing a computer. Other findings derived from the experimental test data are 1 for the closer regions extending even beyond the ring of first impact, the bubble expansion causes the water below the closure depth to rise and thus causes closure to occur at a much earlier time, sine the layer does not have to fall to its original position 2 when the draft of a floating structure is small compared to the thickness of the water layer, the bodily motions of that structure are essentially the same as the water layer, and these motions are relatively independent of the cross sectional shape of the structure and 3 negative reflections from the bottom strong enough to produce cutoff are quite possible even with relatively large pressure amplitudes, and are capable of considerably modifying the region of cavitation.

Subject Categories:

  • Explosions
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE