Magnetic Flowmeter Measurement of Solid Propellant Pressure-Coupled and Velocity-Coupled Responses
Abstract
This report documents a continuation of previous work with the pressure-coupled magnetic flowmeter burner to extend its measurements capacity to include a wider frequency spectrum and variety of propellants. The results obtained in this experimental program extend the operable frequency range of a magnetic flowmeter burner to a lower limit of 200 Hz, well into the range where intermediate frequency instabilities occur. Six formulations of AP-HTPB composite propellant (including one moderately aluminized composition) were successfully tested, and their pressure-coupled response functions measured over the burner's operating frequency range. This research also attempted to directly measure a high-frequency solid propellant velocity-coupled admittance. The velocity-coupled admittance was defined in this research as the complex ratio of the oscillatory mass-flow velocity generated from the surface of a burning propellant to the oscillatory cross-flow velocity above the surface. These oscillatory velocities were measured simultaneously inside a rectangular slab- burning combustion chamber with a magnetic flowmeter. The high-frequency cross flows were created by spinning a spur gear over the sonic nozzle exhaust of the combustion chamber, thus exciting acoustic modes inside the chamber. The admittance results show similar trends under the same burning conditions, and approximate values could be estimated. Keywords: Solid rocket propellants, Combustion stability, Acoustic admittance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1988
- Accession Number
- ADA203988
Entities
People
- A. Colozza
- I. Chung
- M. M. Micci
- R. D. Taylor
Organizations
- Pennsylvania State University