Accession Number:

ADA551163

Title:

Scramjet Isolator Modeling and Control

Descriptive Note:

Doctoral thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT

Personal Author(s):

Report Date:

2011-12-01

Pagination or Media Count:

224.0

Abstract:

The scramjet isolator is a duct in which pressure increases from the inlet to the combustor via a shock train. The shock train leading edge LE location must be controlled in an operational scramjet. A LE location measurement algorithm, dynamic model, and control algorithm were developed and validated with 500 frame per second FPS shadowgraph images in this research. The test apparatus consisted of a direct connect cold-flow high-speed wind tunnel with an adjustable ramp mounted in the tunnel floor. Ramp adjustments changed the tunnel cross-sectional area which changed the tunnel back pressure and LE location. Wall-mounted pressure transducers and a high-speed camera were used for data collection. The LE location measurement algorithm is the first with results validated using 500 FPS shadowgraph images to measure the LE location with root mean square RMS errors less than 20 of a duct height, D, although the transducers were separated by 50 of D. The developed and validated dynamic model is the first with error RMS values less than 24 of D. Finally, the first control algorithm capable of controlling the LE location within 50 of D was developed and validated.

Subject Categories:

  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE