High Density, Long-Term 3D PTV Using 3D Scanning Illumination and Telecentric Imaging

Kitzhofer, J.; Kirmse, Clemens; Brücker, Christoph

doi:10.1007/978-3-642-01106-1_13

Cited by 6 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The illumination of the entire experimental volume was then recorded on a single sensor exposure of each of the three cameras employed and subsequently reconstructed using a pixel line-of-sight technique. In a related PTV work, Kitzhofer et al 19 used the same experimental setup as above but gated the sensors to acquire images for each of 10 scanning volumes. This latter technique is similar to our fast-scan mirror protocol where the mirror is scanned as rapidly as possible across the experimental domain, capturing a single image at each mirror location.…”

Section: A Volumetric Measurements Of Velocitymentioning

confidence: 99%

Scanning tomographic particle image velocimetry applied to a turbulent jet

2013

View full text Add to dashboard Cite

We introduce a modified tomographic PIV technique using four high-speed video cameras and a scanning pulsed laser-volume. By rapidly illuminating adjacent subvolumes onto separate video frames, we can resolve a larger total volume of velocity vectors, while retaining good spatial resolution. We demonstrate this technique by performing time-resolved measurements of the turbulent structure of a round jet, using up to 9 adjacent volume slices. In essence this technique resolves more velocity planes in the depth direction by maintaining optimal particle image density and limiting the number of ghost particles. The total measurement volumes contain between 1 ×106 and 3 ×106 velocity vectors calculated from up to 1500 reconstructed depthwise image planes, showing time-resolved evolution of the large-scale vortical structures for a turbulent jet of Re up to 10 000.

show abstract

Section: A Volumetric Measurements Of Velocitymentioning

confidence: 99%

Scanning tomographic particle image velocimetry applied to a turbulent jet

2013

View full text Add to dashboard Cite

show abstract

“…The resulting 10 % of ghost particles are treated through time-resolved information with predictors based on previous time steps. This increases the accuracy Malik et al (1993); Cierpka et al (2013) and allows to filter ghost particles which typically have a short track length Kitzhofer et al (2009).…”

Section: D Experimental Turbulent Jetmentioning

confidence: 99%

A meshless and binless approach to compute statistics in 3D Ensemble PTV

Ratz,

Mendez

2024

Preprint

View full text Add to dashboard Cite

We propose a method to obtain super-resolution of turbulent statistics for three-dimensional ensemble particle tracking velocimetry (EPTV). The method is "meshless" because it does not require the definition of a grid for computing derivatives, and it is "binless" because it does not require the definition of bins to compute local statistics. The method combines the constrained radial basis function (RBF) formalism introduced Sperotto et al. (Meas Sci Technol, 33:094005, 2022) with a kernel estimate approach for the ensemble averaging of the RBF regressions. The computational cost for the RBF regression is alleviated using the partition of unity method (PUM). Three test cases are considered: (1) a 1D illustrative problem on a Gaussian process, (2) a 3D synthetic test case reproducing a 3D jet-like flow, and (3) an experimental dataset collected for an underwater jet flow at Re = 6750 using a four-camera 3D PTV system. For each test case, the method performances are compared to traditional binning approaches such as Gaussian weighting (Agüí and Jiménez, JFM, 185:447-468, 1987), local polynomial fitting (Agüera et al, Meas Sci Technol, 27:124011, 2016), as well as a binned version of the RBF statistics.

show abstract

“…The tomographic reconstruction methods and the cuboid tracking have been implemented and tested in an experimental set‐up of a vortex ring in a water tank. The experiment has been conducted by the Institute of Mechanics and Fluid Dynamics at TU Freiberg, Germany, in their experimental facility (Kitzhofer et al, 2009b). A vortex ring in a water tank is illuminated by a 3D laser beam device.…”

Section: Sensor and Datamentioning

confidence: 99%

“…The experiments are performed with an image rate of 1000 fps. See Kitzhofer et al (2009a) for more detailed specifications of this experimental set‐up.…”

Section: Sensor and Datamentioning

confidence: 99%

See 1 more Smart Citation

Photogrammetric Techniques for Voxel‐Based Flow Velocity Field Measurement

Westfeld

Maas

2011

The Photogrammetric Record

View full text Add to dashboard Cite

The paper presents improved photogrammetric techniques for the determination of 3D flow velocity fields with the goal of optimising the performance, efficiency and flexibility of the method. This includes a multi‐camera system configuration and calibration, as well as approaches for volumetric reconstruction. The result of the volumetric reconstruction process is a time‐resolved, voxel‐space representation of tracer particles marking a flow. Using a high‐speed camera, a typical data‐set consists of 1000 volumetric data‐sets per second, each with 1000 × 1000 × 300 voxels. 3D tracking in the time‐resolved voxel data is performed by 3D least squares tracking, determining 12 parameters of a 3D affine transformation between cuboids in successive voxel data‐sets. Besides the cuboid translation, these parameters also include information on the shear tensor of each cuboid. The tomographic reconstruction methods and the cuboid tracking have been implemented and validated with both simulated and real data in an experimental set‐up of a vortex ring in a water tank.

show abstract

High Density, Long-Term 3D PTV Using 3D Scanning Illumination and Telecentric Imaging

Cited by 6 publications

References 4 publications

Scanning tomographic particle image velocimetry applied to a turbulent jet

Scanning tomographic particle image velocimetry applied to a turbulent jet

A meshless and binless approach to compute statistics in 3D Ensemble PTV

Photogrammetric Techniques for Voxel‐Based Flow Velocity Field Measurement

Contact Info

Product

Resources

About