Assessment of Various Low-Profile Mechanical Vortex Generators in Controlling a Shock-Induced Separation

An experimental investigation was conducted to assess the effectiveness of five microvortex generator configurations in controlling an incident shock-induced separation associated with a 14 deg shock generator in a Mach 2.05 flow. The vortex generator configurations studied include the Ashill, Anderson, split-Anderson, trapezoidal, and ramp-vane designs. Each device height h spanned 30% of the local boundary-layer thickness delta estimated just upstream of the separation for no control. An array of each control device configuration was implemented 10 delta upstream of the separation location for no control. Additionally, one ramp-vane device with h/delta = 0.5 was also tested. Out of all the configurations tested, the ramp-vane device (h/delta = 0.5) shows the maximum downstream shift (21%) in separation location. This device and the split-Anderson configuration (h/delta = 0.3) both show a reduction in the maximum rms values by 26 and 24%, respectively. The study on ramp-vane devices (h/delta = 0.3, 0.5) further shows that the size of the split relative to the device height also seems to be an important parameter. For the ramp-vane devices (h/delta = 0.3, 0.5), a smaller intervane spacing of 1.7h (h/delta = 0.5) instead of 3h (h/delta = 0.3) shows a very effective control. From this perspective, providing a split size of 1h in split-Anderson device has also shown favorable results.