A STUDY OF RAM TYPE INTAKE PARAMETERS

The subject of this paper is an investigation of the significant factors that affect the performance of a subcavitating pitot type intake for a waterjet propulsion system for hydrofoil craft. A computer model for design of an inlet nacelle is developed which accepts values of two parameters and several system constants from a control program and designs a nacelle to meet those requirements subject to limitations imposed by cavitation and geometry. The parameters are inlet velocity ratio and inlet diameter to maximum diameter ratio. A body of revolution configuration with profile shape based on certain desirable pressure distributions is assumed. Extensive use is made of empirical data from the available unclassified literature. The design conditions are those existing at maximum speed, called cruise speed, and the minimum foil-borne speed, called take-off speed. The subroutine will accept up to three additional speeds at which a performance prediction will be made after design is completed from the first two. Pressure recovery characteristics and cavitation limits for some typical designs are displayed as graphs. The subroutine listing and flow diagram is included in Appendix C. In addition, an alternate design method which accepts only the inlet velocity ratio as a parameter is included in Appendix D.

• Corporate Authors:

  Massachusetts Institute of Technology

  Department of Ocean Engineering, 77 Massachusetts Avenue
  Cambridge, MA  United States  02139
• Authors:
  • Conner, B T
• Publication Date: 1972-6

Subject/Index Terms

• TRT Terms: Hydrofoils; Performance; Water pumps; Waterjet propelled craft; Waterjets
• Old TRIS Terms: Waterjet propulsion; Waterjet pump performance
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00044177
• Record Type: Publication
• Source Agency: Massachusetts Institute of Technology
• Files: TRIS
• Created Date: May 11 1973 12:00AM