Shock-related unsteadiness of axisymmetric spiked bodies in supersonic flow

Shock-related unsteadiness over axisymmetric spiked body configurations is experimentally investigated at a freestream supersonic Mach number of 2.0 0 $$^\circ $$ angle attack. Three different forebody mounted with sharp spike-tip ranging from blunt to streamlined (flat-face, hemispherical, and elliptical) are considered. Steady unsteady pressure measurements, short-exposure high-speed shadowgraphy, shock footprint analysis $$x-t$$ plots, identification dominant spatiotemporal modes through modal carried out explain the flow physics. The present investigation tools validated against well-known events ‘pulsation’ corresponding flat-face case. hemispherical case characterized by formation separated free shear layer associated localized oscillations. cycle charging ejection fluid mass recirculation zone identified drive unsteadiness. Such an event triggers movement reattachment shocks in opposite direction respect each other (out-of-phase motion). In elliptical case, overall field resembles that except dampened value cone ( $$\lambda ) region found responsible for fluctuations caused mass. Thereby, it controls extent out-of-phase motion. reduced as observed be smaller. Based on gathered results understanding, reduction aerodisk demonstrated explained via almost complete elimination