Dynamic Mode Decomposition on Moving Bodies-Moving Processing Window

This study presents an enhanced Dynamic Mode Decomposition (DMD) algorithm for accurately computing DMD modes on moving bodies. To extend DMD to moving bodies, we perform the analysis in the body frame and transform the dynamic characteristics to the inertial frame. In addition to accounting for the induced velocity in the body frame due to relative motion, we address the induced velocity caused by interpolation between frames, particularly for rapid movements. This is achieved by introducing an interpolation map and subtracting it from the flow data. The method is validated using a 2D oscillating cylinder and applied to complex geometries and motions.