Visualization of Baffled Tube Ram Accelerator Internal Flow Using Focused Shadowgraph Imaging

High-speed shadowgraph videography provides both pseudo-quantitative geometric data (such as shock wave angles) and high-fidelity qualitative visualization of the axisymmetric flow fields within Baffled Tube Ram Accelerators (BTRA). The collection of shadowgraph videos of shock wave dynamics of projectile-baffle interactions within the BTRA will enable optimization of projectile and baffle geometries for minimum drag and validation of computational fluid dynamics (CFD) models in future design work. A portable imaging system capable of performing focused shadowgraphy is designed and constructed, and its sensitivity is verified using pistondriven shock waves.