Side-load phenomena in highly overexpanded rocket nozzles
2004 (English)In: Journal of Propulsion and Power, ISSN 0748-4658, Vol. 20, no 4, 695-704 p.Article in journal (Refereed) Published
The operation of rocket engines in the overexpanded mode, that is, with the ambient pressure considerably higher than the nozzle exit wall pressure, can result in dangerous lateral loads acting on the nozzle. These loads occur as the boundary layer separates from the nozzle wall and the pressure distribution deviates from its usual axisymmetric shape. Different aerodynamic or even coupled aerodynamic/structural mechanic reasons can cause an asymmetric pressure distribution. A number of subscale tests have been performed, and three potential origins of side loads were observed and investigated, namely, the pressure fluctuations in the separation and recirculation zone due to the unsteadiness of the separation location, the transition of separation pattern between free-shock separation and restricted-shock separation, and aeroelastic coupling, which indeed cannot cause but do amply existing side loads to significant levels. All three mechanisms are described in detail, and methods are presented to calculate their magnitude and pressure ratio at which they occur.
Place, publisher, year, edition, pages
2004. Vol. 20, no 4, 695-704 p.
Aerodynamics, Boundary layers, Friction, Nozzles, Pressure effects, Sea level, Specific heat, Strain gages
IdentifiersURN: urn:nbn:se:kth:diva-43641ISI: 000222836200013ScopusID: 2-s2.0-3843080639OAI: oai:DiVA.org:kth-43641DiVA: diva2:448716
QC 20111018. AIAA/ASME/SAE/ASEE 37th Joint Propulsion Conference. SALT LAKE CITY, UTAH. JUL 08-11, 2001 2011-10-182011-10-172011-10-18Bibliographically approved