WATER-ENTRY CAVITY MODELING. PART I. VERTICAL CAVITIES

Abstract

Modeling studies were conducted with a 2 inch diameter hemisphere head missile as a prototype and with 1- and l/2-inch-diameter models of the prototype. This "modeling with models" program was carried out to investigate the importance of gas density scaling in conjunction with Froude and cavitation number scaling in water entry cavity modeling. The observation of the cavities formed by the vertical entry of those model. showed that one-to-one scaling of the Froude and cavitation numbers and of the gas density coefficient modeled the cavity to a high degree of accuracy. Failure to scale the cavitation number did not prevent good modeling. but when the gas density coefficient was not scaled modeling did not occur. Good water penetration distance modeling obtained for all modeling conditions. Evaluation of the importance of atmospheric density scaling on water entry modeling must be deferred until tests are extended to include launchings of models at oblique angles. Cavitation number scaling cannot be disregarded in the general water entry modeling problem because it has been found necessary to model missile motion in oblique water entry.

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Document Details

Document Type
Technical Report
Publication Date
Oct 08, 1956
Accession Number
AD0128957

Entities

People

  • G. W. Stubstad
  • J. G. Waugh

Organizations

  • Naval Air Weapons Station China Lake

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Atmospheric Density
  • Barometric Pressure
  • Bodies
  • California
  • Frequency
  • Froude Number
  • Measurement
  • Munitions
  • Ordnance Laboratories
  • Oscillation
  • Pressure Measurement
  • Steady State
  • Vapor Pressure
  • Variable Pressure
  • Vibration
  • Water Tunnels

Readers

  • Computational Modeling and Simulation
  • Fluid Dynamics.
  • Underwater engineering and Marine Technology.