Accession Number:

ADA080220

Title:

Rotating Valve for Velocity Coupled Combustion Response Measurements.

Descriptive Note:

Final scientific rept.,

Corporate Author:

UNITED TECHNOLOGIES CORP SUNNYVALE CALIF CHEMICAL SYSTEMS DIV

Personal Author(s):

Report Date:

1979-11-01

Pagination or Media Count:

80.0

Abstract:

GSD has investigated the dual valve approach for measuring propellant velocity coupled characteristics. Analytical studies have developed a mathematical analysis of the transient ballistics. The solution of the transient mass, momentum, and energy equations incorporates both linear and nonlinear velocity coupling, as well as pressure coupling, particle damping, flow turning, and nozzle losses in the analysis. The analysis shows that velocity coupling dominates the system response when the two valves operate 180 deg out of the phase. The analytical solutions agree with known solutions for low frequency, bulk mode conditions and for the frequency response characteristics at acoustic resonance. Studies were conducted to explore the limitations of the dual valve approach and to estimate the effects of experimental uncertainties. Parametric studies using the linear velocity coupling model indicated properties of the solution that suggested an approximate method for deriving the response from pressure data using the linear velocity coupling assumption. Parametric studies were also made using the nonlinear velocity coupling model. The results show the interaction of mean velocity magnitude, threshold velocity, and amplitude of the velocity oscillation on the predicted pressure oscillations. A method was developed to derive the velocity response from experimental data for a given threshold velocity, but no method was found for deriving threshold velocity from experimental data.

Subject Categories:

  • Numerical Mathematics
  • Combustion and Ignition
  • Solid Propellant Rocket Engines
  • Solid Rocket Propellants

Distribution Statement:

APPROVED FOR PUBLIC RELEASE