NASA STI Program | On the Comparison of the Long Penetration Mode (LPM) Supersonic Counterflowing Jet to the .. @NASASTIProgram | Uploaded November 2015 | Updated October 2024, 23 hours ago.
Classic tonal screech noise created by under-expanded supersonic jets; Long Penetration Mode (LPM) supersonic phenomenon -Under-expanded counter-flowing jet in supersonic free stream -Demonstrated in several wind tunnel tests -Modeled in several computational fluid dynamics (CFD) simulations; Discussion of LPM acoustics feedback and fluid interactions -Analogous to the aero-acoustics interactions seen in screech jets; Lessons Learned: Applying certain methodologies to LPM -Developed and successfully demonstrated in the study of screech jets -Discussion of mechanically induced excitation in fluid oscillators in general; Conclusions -Large body of work done on jet screech, other aero-acoustic phenomenacan have direct application to the study and applications of LPM cold flow jets. For the Oral/Visual Presentation in which this video was presented, please see the following link in the NASA Technical Reports Server (NTRS, http://ntrs.nasa.gov): hdl.handle.net/2060/20150016244