Accession Number:

AD0772931

Title:

Percussive Water Jets for Rapid Excavation.

Descriptive Note:

Final rept. 28 Dec 72-31 Dec 73,

Corporate Author:

SCIENTIFIC ASSOCIATES INC SANTA MONICA CALIF

Report Date:

1973-12-01

Pagination or Media Count:

63.0

Abstract:

A preliminary experimental investigation on the feasibility of producing percussive water jets and their potential utility for rock excavation was conducted. A percussive jet applies force to the rock as a series of high-frequency impact, rather than steadily. Percussive jets can be produced by modulating the jet discharge, i.e., by cycling the discharge rate above and below its average. Flow modulation suitable for testing was obtained by means of a cyclically varying flow resistance upstream of the discharge nozzle. Modulated free stream effects were observed by stroboscopic light and percussive impact was observed by means of a piezoelectric force gauge with high-frequency response. Modified author abstract

Subject Categories:

  • Mining Engineering
  • Civil Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE