Accession Number:

ADA056937

Title:

Design and Evaluation of a Facility to Study Two-Dimensional Supersonic Air-Helium Mixing.

Descriptive Note:

Final rept.,

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING

Personal Author(s):

• Carlile,John D.

Report Date:

1978-03-01

Pagination or Media Count:

47.0

Abstract:

A facility to study two-dimensional supersonic air-helium mixing in a gas dynamic laser cavity was designed, constructed, and evaluated. The flow field may be analyzed via static and total pressure measurements, gas mixture samples, and schlieren photography. The multiple nozzle test section consisted of Mach 3.0 air nozzles alternated with Mach 3.0 helium nozzles exhausted into an instrumented test cavity. Pressure was maintained in the cavity by two alternate methods simple diffusers exhausted to atmospheric conditions, and exhausting the cavity into a group of evaculated air tanks. Both methods gave similar cavity flow fields as indicated by schlieren photography and static pressure measurements. Gas samples and pressure measurements were taken with a series of small diameter probes and automatically timed solenoid valves. Gas samples were not analyzed in this study. Nozzle exit plane Mach numbers were calculated from pressure measurements and verified with schlieren photographs of a wedge inserted into the flow. The apparatus has low helium consumption and yields accurate, repeatable pressure measurements. The facility is to be used for a subsequent complete flow field analysis. Author

Descriptors:

• *JET MIXING FLOW
• *GAS DYNAMIC LASERS
• AIR
• THESES
• CAVITIES
• FLOW VISUALIZATION
• PRESSURE MEASUREMENT
• FLOW FIELDS
• MIXING
• HELIUM
• SUPERSONIC FLOW
• NOZZLE GAS FLOW
• SCHLIEREN PHOTOGRAPHY

Subject Categories:

• Lasers and Masers
• Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE