Experimental and Theoretical Investigation of Base-Flow Buffeting on Ariane5 Launch Vehicles

Experimental analysis of the pressure–velocity correlations of external unsteady flow over rocket launchers

“…These effects are shown schematically in Fig. 4 and correspond exactly to the structural modes of the nozzle [9,20,25].…”

“…Wong et al [25] analyzed wall pressure measurements obtained from more than 40 pressure transducers distributed uniformly over the Ariane 5 after-body. These measurements have been conducted with different free-stream Mach numbers ranging from 0.4 to 0.9.…”

Control of base pressure for a boat-tailed axisymmetric afterbody via base geometry modifications

“…The spectra for M ∞ of 0.8-0.9 show a broad peak the vortex shedding of large-scale turbulent structures for axisymmetric bluff bodies [24,37]. The spectra between M ∞ of 0.8-0.9 also show dominance of three discrete frequencies centered around [22,24,26,28]. The amplitude of these frequencies is however seen to decrease with increase in M ∞ .…”

“…Another challenge associated with these control strategies is the reduction of base pressure fluctuations that are often associated with a turbulent separated flow, to alleviate the dynamic loading on the nozzle structure of the missile/launcher [24,25]. A serrated skirt (which in principle acts as a base cavity studied earlier [1]) added to the launch vehicle tail end is reported to reduce the pressure and side-load fluctuations on the external nozzle [26]. However the serrations were not observed to modify the spatial organization of the separated flow region.…”

From pressure fluctuations to dynamic loads on axisymmetric step flows with minimal number of kulites

“…The survey of buffet loads and internal side loads have been the subject of numerous publications [1,18,19,25]. The load measurement problem highlighted in the literature [13] is found to be the same for our interest in external side loads.…”