Three-dimensional shock wave/boundary layer interactions on compression corners*

Shock wave/Boundary Layer Interactions (SBLI) are a typical hallmark of high-speed aerodynamics.

SBLI often cause extensive reversed flow, with associated low-frequency unsteady pressure loads generated from the reflected shock motion.

These phenomena pose serious concerns to aircraft design, since pressure fluctuations can trigger fluid-structure interaction phenomena with potential structural damage and performance decrease.

Most SBLI studies, both experimental and numerical, focus on two-dimensional configurations, where the shock impingement line is orthogonal to the incoming flow. In practical applications, the line where the shock impinges is rarely orthogonal to the incoming flow, which results at an angle with respect to the nominal impigment line. Depending on the shock strength and sweep angle, the interaction exhibits either parallel or divergent separation/reattachment lines along the spanwise direction, featuring a cylindrical or conical symmetry, respectively.

In this context, we deem it valuable to gain a more profound insight into the physical mechanisms driving low-frequency unsteadiness in swept SBLI. To this aim, we utilize a newly developed DNS dataset of supersonic turbulent compression ramp flow, where the flow sweep angle is systematically varied.

We plan to analyze frequency-wavenumber spectra of wall pressure distribution to deduce the characteristic length and velocity scales of the phenomenon. Based on these findings, we intend to derive a scaling law for the typical frequencies of pressure fluctuations.