Combined Application of Particle Image Velocimetry (PIV) and Laser Doppler Anemometry (LDA) to Swirling Flows Under Compression
The velocity field of a strongly swirling flow has been examined using an LDA and PIV in combination. The PIV revealed an asymmetric component of the flowfield, in particular a movement of the swirl center away from the geometric center of the rotating cylinder. A statistical description of this asymmetric component has been developed, from which the apparent turbulence measured with an LDA has been estimated. These results are compared to the actual LDA measurements. The conclusion is that a large portion of the measured turbulence using a one point technique (LDA) can be attributed to this effect and can also explain the previously observed discrepancy between experiment and numerical simulation.
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- Brereton, G.J. And Kodal, A. (1991) A Frequency-Domain Filtering Technique for Triple Decomposition of Unsteady Turbulent Flow Google Scholar
- RASK, R.B. (1981) Comparison of Window, Smoothed-Ensemble and Cycle-to-Cycle Data Reduction Techniques for Laser Doppler Anemometer Measurements of in-Cylinder Velocity, Fluid Mechanics of Combustion Systems, ed. Morel, T., Lohmann, R.P. and Rackley, J.M., 11–20, ASMEGoogle Scholar
- HILTON, A.D.M., ROBERTS, J.B. AND HADDED, O. (1991) Autocorrelation Based Analysis of Ensemble Averaged LDA Engine Data for bias-free Turbulence Estimates: A Unified Approach, SAE 910479Google Scholar
- Jakirlic, S. And Hanjalic, K. (1995) A Second-Moment Closure for Non-Equilibrium and Separating High- and Low-Re-Number Flows, Proc. 10th Symposium on Turbulent Shear Flows, The Pennsylvania State University, USA, August 14–16Google Scholar
- ABRAMOWITZ, M. AND STEGUN, I.A. (1970) Handbook of Mathematical Functions, New York, S. 892f.Google Scholar