Effect of Nonuniform Entrance Flow Profile on Hypersonic Nozzle Pitching Moment
Abstract
The Scramjet Hypersonic Nozzle (SCHNOZ) parabolized Navier-Stokes computer code was used to model turbulent, chemically reacting flow present in a hypersonic nozzle. Two nozzle configurations were considered, an isolated nozzle (no external flow) and a nozzle with a finite length cowl. A single nonuniform entrance flow profile was generated and an equivalent uniform flow profile calculated for input into the nozzle code. Uniform and nonuniform cases for each nozzle were run using both frozen and finite rate chemistry. An increased grid resolution in the computer code was necessary to eliminate numerically induced anomalies in the results of the nonuniform cases for both nozzle configurations. Comparisons between the finite rate and frozen flow cases showed that chemistry was essentially frozen for the finite rate cases, indicating that for the nozzle inlet conditions and geometry used in this study, the extra computational time spent on finite rate kinetics was unnecessary. The effects of the nonuniform flowfield used in this study included an increase in the overall vehicles thrust and a decrease in the overall vehicle moment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1991
- Accession Number
- ADA244050
Entities
People
- Sandra L. Snelling
Organizations
- Air Force Institute of Technology