Operation Upshot-Knothole. Project 1.1d Dynamic Pressure versus Time and Supporting Air Blast Measurements

Abstract

Project 1.1d of Operation UPSHOT-KNOTHOLE measured dynamic pressures in the shock wave and preshock pressures. It also conducted a feasibility study of new and modified gages to measure dynamic pressure, density, temperature, and particle velocity. Measured dynamic pressures can be compared with those calculated from the measured overpressures using the Rankine-Hugoniot shock relations and regular reflection theory. When no precursor is formed, measured dynamic pressures are in reasonable agreement with those calculated although some effects of thermal and mechanical interaction are noted. Dynamic pressures measured in the precursor are much higher than those calculated. Laboratory tests have indicated that the end instrument used does respond to dust as well as to air, and the quantity measured by these gages is apparently (1/2 rho u-squared)air + (rho u-squared)dust when dust is present in the shock wave, as is true in the precursor. Measurements have shown a few instances of real but small preshock increases in air pressure, all apparently caused by thermal radiation alone.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1954
Accession Number
ADA076361

Entities

People

  • C. D. Broyles

Tags

Communities of Interest

  • Air Platforms
  • Counter WMD
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Pressure
  • Blast
  • Dynamic Pressure
  • Explosions
  • Ground Zero
  • Height Of Burst
  • Measurement
  • Overpressure
  • Pressure Gages
  • Pressure Measurement
  • Pressure Transducers
  • Radiation
  • Recording Systems
  • Shock Tubes
  • Shock Waves
  • Static Pressure
  • Waveforms

Readers

  • Combustion Dynamics and Shock Wave Physics.