Abstract
An experimental study of scramjet asymmetric nozzle flowfields is conducted to investigate the effects on nozzle performance of interactions between engine exhaust and hypersonic external flow. The test model consists of a flat-plate ramp and a short cowl. Tests are performed in a hypersonic wind tunnel (Mx = 7.1) whose freestream constitutes the external flow around an aerospace plane. Room temperature air is used to simulate engine exhaust flow. Model surface pressure and pitot pressure distributions in the flowfields are measured, from which nozzle performance is calculated. Flow visualizations are performed using several techniques. It is found that in underexpansio n conditions, the external flow affects the model surface pressure only from the ramp sides because the intercepting shock (barrel shock) does not impinge upon the ramp surface. It is shown that the external flow produces an effect which suppresses boundary-layer separation on the ramp surface. When using a long side fence (SF), span wise expansion of the exhaust flow is restrained, thus, a slight gain of thrust can be obtained relative to that using a shorter side fence. The predicted nozzle performance by the twodimensional method of characteristi cs with boundary-layer correction agrees well with the long side fence experimental results.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
