High-Resolution, High Frequency, Real-Time Optical Flow Particle Image Velocimetry
J. Pimienta(1,2), J.L. Aider(2)
1: Photon Lines, 10 avenue des Touches, Pacé, 35740, France.
2: PMMH Laboratory, UMR7636 CNRS, ESPCI Paris, PSL Research University, Sorbonne Université, University Paris Diderot, 7-9 quai Saint Bernard, 75005 Paris, France.
DOI:
Particle image velocimetry (PIV) is a non-intrusive method that allows for the estimation of velocity fields from particle displacement in a scene. We present in this work advances in Live-Optical Flow Particle Image Velocimetry (L-OF-PIV). We validate the precision of the displacement field estimation using an homogeneous isotropic turbulence (HIT) DNS (Direct Numerical Simulation) dataset. We also present advances in the computing performances of the Live measurements, achieving real-time velocity fields estimation at more than 2 kHz with 1 Mp images, up to 1.1 kHz with 4 Mp images, and up to 200 Hz with 21 Mp images. We provide experimental validation by monitoring the flow past a cylinder, at ReD ≈6482, for more than 4 hours at an acquisition frequency fac = 100 Hz. Moreover, velocity-derived quantities were extracted in real-time to explore phenomena that would be complicated or impossible to capture with conventional post-processing. Overall, we demonstrate that L-OF-PIV now enables complex fluid flow estimation with dense velocity fields (one vector per pixel) at high frequencies in both mono- and multi-GPU configurations, in real-time and over extended periods of time.
