Accession Number:

AD0392072

Title:

ACOUSTIC LINERS FOR STORABLE PROPELLANT ROCKET CHAMBERS - PHASE II

Descriptive Note:

Final rept. 28 Mar 1967-31 May 1968

Corporate Author:

PRATT AND WHITNEY AIRCRAFT WEST PALM BEACH FL FLORIDA RESEARCH AND DEVELOPMENT CENTER

Report Date:

1968-08-27

Pagination or Media Count:

223.0

Abstract:

The work consisted of three interrelated tasks 1 the establishment and testing of a theory and design procedure for nonresonant absorbers 2 the evaluation of the effects on liner performance of coolant flow through andor past the liner apertures and 3 the evaluation of ablative liners. The types of cooled liners that were studied were transpiration liners wafer and porous types, film-cooled, and ablative liners. Impedance data were obtained on transpiration and ablative-type liner samples and the results applied to liner design theory. The film-cooled liners demonstrated stable combustion when no cooling and low cooling flows were used, but the combustion became progressively more unstable as cooling flow was increased. The wafer liner provided stable operation when no cooling was used but combustion was extremely unstable when hydrogen cooling was introduced. The test results show that when the chamber or liner wall is cooled externally with a film layer, or transpirationally, combustion stability varied inversely with the coolant flowrate. A dual-open area parallel array ablative liner was effective in suppressing combustion oscillations but an ablative liner with individual resonators failed to stabilize combustion. From the results of this program it was concluded that nonresonant absorbers are not as effective in suppressing combustion oscillations as are resonant absorbers.

Subject Categories:

  • Acoustics
  • Combustion and Ignition
  • Liquid Propellant Rocket Engines
  • Liquid Rocket Propellants

Distribution Statement:

APPROVED FOR PUBLIC RELEASE