  The intakes of air-breathing high-speed flying vehicles produce a large share
of the thrust propulsion. Furthermore, the propulsion performance of these
engines increases when the single-ramp intake is replaced with a multiple-ramps
intake. Many scholars numerically and experimentally studied the high-speed
engine performance over static single and multiple compression ramps. However,
the transient behavior of the flow during the rotation of the double
compression ramp from a single ramp is not fully investigated. The present
paper aims to numerically investigate the transient shock reflection phenomenon
over a rotating double wedge. The problem will start with a 3-Mach number
inviscid flow over a single wedge. Then, a portion of the wedge will be rotated
upstream at a quite low trailing Mach number to avoid the significant lag
effect in the shock waves system. This idea could be applied in the supersonic
intake or extensionally in the hypersonic intake of scramjets with a somehow
complex mechanism. Further, the length of the rotating portion of the wedge
will be changed three times to study its effect on the shock system. The
results show a high gain in the pressure due to the rotation of the wedge.
Moreover, the wave angles were larger at the low chord ratio value of $w_2/w_i=
0.25$ than at the high values of $w_2/w_i$ at the same second wedge rotating
angle, $\theta_2$, resulting in a higher pressure distribution.
