Nozzle heating and cooling patterns for improved hypersonic quiet wind-tunnel design.
Abstract
Variations in wall temperature have long been known to affect the growth of first- and second-mode instability, with the standard rule of thumb that whole-wall-heating dampens second-mode growth and enhances first-mode growth (and opposite occurs for whole-wall cooling). However, as our understanding of the fundamental physical processes governing first- and second-mode dynamics evolved, this general rule of thumb required revision. Recently, it has shown that localized wall temperature variations can be exploited to alter the acoustic second-mode growth without adverse first-mode growth. Consistent with the thermoacoustic interpretation of second-mode instability, such wall temperature variations represent a fluid-structure interaction in which the thermal boundary layer is modulated by localized wall heating-cooling. This modulation locally ‘tunes-detunes’ second-mode instabilities of differing frequencies, thus disrupting the integrated disturbance growth. Through a combined numerical-experimental approach, it is the objective of this work to exploit such patterned wall temperature variation to improve hypersonic quiet wind tunnel nozzle design. This research will be conducted in the AFOSR–Notre Dame Large Mach-6 Quiet Tunnel, with preliminary investigation conducted on a canonical straight cone model.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2023
- Source ID
- FA95502210017
Entities
People
- Joseph Kuehl
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Delaware