FlowMaster 3D-PTV / Shake-the-Box

Shake-the-Box is the most advanced 3D Lagrangian Particle Tracking Velocimetry (PTV) method for densely seeded flows at highest spatial resolution. Compared to the voxel-based Tomo-PIV approach Shake-the-Box is a purely particle-based technique using an Iterative Particle Reconstruction (IPR) technique in combination with an advanced 4D-PTV algorithm using the time-information for track reconstruction. Shake-the-Box achieves a higher reconstruction accuracy at much faster processing speed compared with its TR-Tomo-PIV counterpart.
Beside different DaVis software packages FlowMaster systems for TR-Tomo-PIV and Shake-the-Box are using the same hardware.

FlowMaster Shake-the-Box
System Features
  • time-resolved PTV for 4D flow analysis at high seeding densities
  • award-winning particle reconstruction and tracking algorithm:
    4th International PIV Challenge
  • unsurpassed precision for velocity and acceleration of particle tracks
  • very fast processing speed
  • hardware compatible with FlowMaster TR-Tomo-PIV setups
Flow field of a large thermal air plume calculated with Shake-the-Box applying Helium-filled soap bubble seeding,
courtesy DLR Goettingen

Large Scale PIV/PTV in air

Air seeding with µm-particles is not suitable for large scale PIV/PTV experiments due to their limited scattering power. Neutrally buoyant Helium-filled Soap Bubbles (HFSB) with a diameter of 0.3 mm and a response time less than 15 µs scatter 10000x more light than µm-particles and, therefore, are suitable for large scale PIV/PTV experiments in the lower subsonic regime.
LaVision’s HFSB Seeding Generator can deliver 0.3 mm mono-sized bubbles at a production rate of 40000 bubbles per second and per nozzle and can operate simultaneously up to 60 nozzles in parallel. The typical life time of the Helium-filled soap bubbles is a few minutes. Furthermore, the increased scattering intensity allows to switch from laser to LED illumination, greatly reducing the cost of the light source.

Time-Resolved 3D Flow Field Imaging in a Wind Tunnel for Full Scale Automotive Testing

Time-resolved 3D flow fields have been successfully measured behind a serial car in a large wind tunnel at Volkswagen. The field-of-view was 2 m x 1.6 m with a light sheet thickness of 0.2 m. The air flow was seeded with 0.3 mm in diameter Helium-filled soap bubbles applying seeding rates of more than 2 million bubbles per second operating 60 seeding nozzles.

Four high-speed cameras recorded the 3D wake flow at wind speeds of 60 km/h and 120 km/h, respectively. A high-speed laser was used for illumination. LaVision’s Shake-the-Box time-resolved 3D-PTV technique was applied to calculate the time-resolved 3D flow fields.