Accession Number : ADA206099

Title :   Flow-Turning Losses in Solid Rocket Motors.

Descriptive Note : Final rept. Jul 81-Mar 88,

Corporate Author : HERSH ACOUSTICAL ENGINEERING CHATSWORTH CA

Personal Author(s) : Hersh, Alan S ; Tso, Jin

PDF Url : ADA206099

Report Date : Mar 1988

Pagination or Media Count : 66

Abstract : Results are presented of an experimental and analytical investigation of the flow-turning losses resulting from the injection of ambient air into an acoustically energized duct. Measurements show that acoustic energy is absorbed. In all test cases, however, the sound energies absorbed by the finite admittance duct side walls were significantly larger than that absorbed by the injected flows. One dimensional steady state and transient flow-turning solutions were derived. For the special case of rigid walls and low injection rates, the steady-state solutions showed that the flow-turning losses were approximately equal to 10 Log (1-Mav) where Mav is the average Mach number across the duct cross-section. The one-dimensional solutions inadequately predicted the measured acoustic energy losses. The transient solutions compared very favorably with Culick's model. Both estimated almost the same decay constants. Sound absorption, Sound attenuation, Sound flow acoustic losses, Combustion instability. (mjm)

Descriptors :   *ACOUSTIC ATTENUATION, *COMBUSTION STABILITY, *FLOW, *SOLID PROPELLANT ROCKET ENGINES, ACOUSTIC ABSORPTION, ACOUSTIC WAVES, ACOUSTICS, AIR, CONSTANTS, CROSS SECTIONS, DECAY, DUCTS, ENERGY, INJECTION, LOSSES, LOW RATE, MACH NUMBER, ONE DIMENSIONAL, RIGIDITY, SOLUTIONS(GENERAL), SOUND, STEADY STATE, TRANSIENTS, WALLS

Subject Categories : Solid Propellant Rocket Engines
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE