Accession Number : AD0744623

Title :   Longitudinal Mode Acoustic Losses in Short Nozzles.

Descriptive Note : Research rept.,

Corporate Author : NAVAL WEAPONS CENTER CHINA LAKE CALIF

Personal Author(s) : Zinn,Ben T.

Report Date : JUN 1972

Pagination or Media Count : 27

Abstract : The report is a revision of a previous report AD-728 754 that investigated longitudinal mode acoustic losses in short nozzles. In the present report the analysis of nozzle acoustic losses has been extended to rigorously account for second order effects. It is shown herein that when the time average of the mass flux in the wave is zero, the nozzle acoutic losses can be expressed in terms of first order quantities only. It is also shown that the term describing the nozzle acoustic losses is the flux term in an equation that describes the instantaneous conservation of wave energy in the presence of mean flow. The revised report establishes the relationship between nozzle acoustic losses and the expressions used to calculate the nozzle decay coefficient. (Author)

Descriptors :   (*ROCKET ENGINE NOISE, ATTENUATION), (*ROCKET NOZZLES, ROCKET ENGINE NOISE), OSCILLATION, SCREAMING COMBUSTION, NOZZLE THROATS, NOZZLE AREA RATIO, SPECIFIC HEAT, STAGNATION POINT, MATHEMATICAL ANALYSIS

Subject Categories : Acoustics
      Rocket Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE