The report investigates several ways of improving water jet delivery in order to increase the efficiency of hydraulic tunneling and mining. These approaches are directed toward the reduction of water jet velocity decay by suppressing pressure disturbances and turbulence which cause jet breakup, by such means as the use of turbulence suppressing chemical additives, the design of a minimum transverse turbulence nozzle, and the suppression of air shear on a free water jet by providing the jet with a moving air sheath. In addition, an investigation is made of the use of a Fluidic Jet Modulator to generate liquid slugs which would produce high pressure impulsive shocks when impacting upon a rock face. A survey is made of the various modes of rock fracture in order to relate the results of the investigation to the problems of tunneling or mining. An evaluation is made of each of the separate studies as to its applicability to tunneling and its technical and economic feasibility. Finally, a system is proposed which incorporates the most effective results of the investigation. (Author)

  • Corporate Authors:

    Bowles Engineering Corporation

    Silver Spring, MD  United States 
  • Publication Date: 1968-4

Media Info

  • Pagination: 119 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00039039
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: BEC-R-4-23-68 Final Rpt
  • Contract Numbers: 7-35381t
  • Files: TRIS
  • Created Date: Nov 24 1973 12:00AM