[en] The effect of nozzle aspect ratio on the mixing promotion capability of limiting tabs fixed at the exit of a Mach 2 convergent−divergent elliptical nozzle has been investigated experimentally. Limiting tabs of flat, triangular, circular arc and circular (crosswire) geometry placed along major and minor axes were studied in the presence of various levels of pressure gradient corresponding to NPR 4 to 8. These NPRs for Mach 2 flow correspond to highly overexpanded to marginally underexpanded states at the nozzle exit. In each case, the blockage offered by a limiting tab at the nozzle exit was 5% of the nozzle exit area. Among the tabs studied, the triangular tab was found to be the most efficient mixing promoter for this Mach 2 elliptical jet. The triangular tab promotes mixing to the largest extent when placed along the minor axis, leading to a core length reduction of about 82%, in the presence of adverse pressure gradient of about 36%, at the nozzle exit—that is, at NPR 5. At this NPR, circular arc and flat tabs protect the core—that is, these tabs retard the jet mixing, leading to an elongation of the core by 8.7% and 42.4% respectively, whereas the core reduction caused by crosswire is only 36.8% at this NPR. The triangular tab is also found to be most efficient mixing promoter for tab orientation along the major axis, but for this orientation the best core length reduction caused is only 73.4%, at NPR 8. The efficient mixing promotion caused by the triangular tab does not introduce any abnormal level of asymmetry to jet propagation. (paper)