Accession Number:

AD0850142

Title:

Advanced Penetration Problems. Volume 2. Wake Structure Measurements

Descriptive Note:

Final rept. 15 Oct 1967-15 Oct 1968

Corporate Author:

PHILCO-FORD CORP NEWPORT BEACH CA SPACE AND RE-ENTRY SYSTEMS DIV

Personal Author(s):

Report Date:

1968-10-31

Pagination or Media Count:

179.0

Abstract:

This report summarizes experimental work done on the structure of compressible turbulent wakes and turbulent plasmas. Detailed point measurements in the two dimensional wake, made very far from the body, have fully confirmed the predictions of the Dynamic Equilibrium Hypothesis regarding the asymptotic values of the Velocity and temperature fluctuation and the statistics of the interface. For flight at angle of incidence radical changes in the wake structure have been observed, while heat transferred from the model to the flow was found to delay greatly the onset of transition to turbulence. In the plasma jet transition zone the remnants of the laminar fluid create a turbulent fluid of highly heterogeneous electron density with hitherto unexpected statistics. The longitudinal scales of the electrons are larger than those of the temperature but numerically not much different from low-speed turbulence scales. The electron density fluctuations always predominate the temperature fluctuations especially at the higher frequencies. Spectral decay obtains a -5 3 range for the temperature but this behavior is not observed for the electrons.

Subject Categories:

  • Countermeasures
  • Fluid Mechanics
  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE