Researchers Develop Framework for Measuring Hydrodynamic Forces on Oscillating Bodies at Fluid Interfaces
Scientists studied how floating planar bodies experience resistance when oscillating laterally along an air-water interface, using magnetic actuation to measure their response across different frequencies and conditions. The research applies oscillatory Stokes boundary-layer theory to predict both steady-state and transient hydrodynamic behavior. The work establishes a new experimental platform for quantifying unsteady hydrodynamic forces, with applications to understanding fluid-structure interactions at interfaces.
Researchers conducted an experimental study of floating planar bodies undergoing lateral oscillations at air-water interfaces to characterize hydrodynamic resistance. Using magnetic actuation, they drove interfacial bodies harmonically and measured amplitude response and phase lag across a range of frequencies, masses, sizes, and shapes. Scaling arguments and oscillatory Stokes boundary-layer theory provided theoretical predictions for the flow behavior at high Womersley numbers and small oscillation amplitudes. The team extracted effective added mass and damping coefficients from their frequency-response measurements, finding good agreement with boundary-layer theory predictions when interfacial deformation remained small. The transient startup behavior was also accurately predicted using a history integral approach. This work establishes a simple experimental platform for quantifying unsteady hydrodynamic forces at fluid interfaces.
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- arXiv physicsCenter
Hydrodynamic Resistance on Oscillating Planar Interfacial Bodies
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