PIV + InfraRed (IR)

Particle Image Velocimetry and Infared Tomography for the characterization of coherent structures in the near-wall region

We investigated the flow field in a turbulent boundary layer in a flume, by using Particle Image Velocimetry (PIV) and Hot-Foil Infrared Imaging (HFIRI) techniques. Coherent patterns in the flow were identified and characterized by using instantaneous velocity and temperature fields. The velocity fields in the streamwise–spanwise plane were measured in parallel to the temperature distribution of the flume bottom. The identified patterns are represented by means of their spatial characteristics – a non-dimensional spatial separation between streamwise patterns, \lambda^+.

PIV-IR

Fig. 1. Schematic view of the combined PIV–HFIRI experimental setup

Measurement principle

IR_image

Fig. 2. Infrared image of the temperature field of the foil surface

Enhanced image

Fig. 3. Enhanced image of the temperature field

RESULTS

Fig. 9. Fluctuating velocity vector field measured by using PIV

Fig. 4. Fluctuating velocity vector field measured by using PIV and the fluctuating temperature field measured by using the HFIRI technique

References

Gurka R., Liberzon, A. and Hetsroni, G. (2004) “Detecting coherent patterns in a flume by using PIV and IR imaging techniques”, Experiments in Fluids, 37(2), pp. 230-236.