Short Description
Optical system for the high-speed measurement of time-resolved, three-dimensional velocity fields in turbulent channel flows.
The system consists of pulsed illumination source (laser, up to 10 kHz) and 4 high-speed cameras (up to 4Mpx).
The flow is seeded with small particles (tracers) that are used to reconstruct the velocity field.
The system is also used to study the dynamics of fibres (length 1 millimeter, diameter 10 micrometer) carried by the flow.
Contact Person
Univ.Prof. Dipl.-Ing. Dr.-Ing. Alfredo Soldati
Research Services
Optical system for the high-speed measurement of time-resolved, three-dimensional velocity fields in turbulent channel flows.
The system can be used to study either the turbulent flow field in a water channel, or to investigate the dynamics of non-axisymmetric object in turbulent flows. Further details available in [1].
[1] Alipour, De Paoli, Ghaemi and Soldati, Long non-axisymmetric fibers in turbulent channel flow, Journal of Fluid Mechanics (2021)
Methods & Expertise for Research Infrastructure
Flow velocity measurements:
The laser illuminates the field of view at a frequency corresponding to the cameras acquisition rate.
The images are stored and preprocessed via DaVis 10 (LaVision GmbH). The velocity field is finally obtain from particle tracking velocimetry (Shake-The-Box). For further details, see [1].
Fibre tracking and velocimetry:
When the flow is seeded with fibres (non-axisymmetric particles), MART is used to reconstruct the fibres orientation and distribution.
First, images are processed with Davis 10 (LaVision GmbH). Then, a MatLab-based in-house code is used to identify the orientation and distribution of the fibres. For further details, see [1].
[1] Alipour, De Paoli, Ghaemi and Soldati, Long non-axisymmetric fibers in turbulent channel flow, Journal of Fluid Mechanics (2021)