Abstract
The flow around two bluff bodies in tandem is an interesting phenomenon whose nature strongly depends on the distance between the bodies. In this work oil smoke visualizations of the flow around two normal flat plates in tandem configuration are compared with phase averaged Laser Doppler Anemometry measurements of the flow field for a full period. Phase averaging is exploited to resolve the mean time evolution of the flow and the signal from a single constant temperature hot wire probe is employed as phasing reference. The flow-field information obtained from visualizations agrees well with quantitative indications provided by measures, and the comparison allows to precisely understand what information can be extracted from simple visualizations. As a result, new insight in flow mechanism is obtained from the analysis of the flow data showing that, for the analyzed plate distance, the gap between the two plates behaves substantially as a cavity while the vortex formation process takes place in the wake region behind the aft plate.
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Franco Auteri: He received his MSc. degree in Aeronautical Engineering in 1996 from Politecnico di Milano and his Ph.D. in Aerospace Engineering in 2000 from the same university. He has been working in the Aerodynamics Laboratory of the Aerospace Engineering Department, Politecnico di Milano, since 2001. He became assistant professor of fluid dynamics at the Industrial Engineering Faculty of Politecnico di Milano in 2005. His research interests are related to experimental and computational fluid mechanics.
Marco Belan: He received his MSc. in Physics in 1991 from Università di Torino and his Ph.D. in Aerospace Engineering in 1995 from Politecnico di Torino. He has been working in the Aerodynamics Laboratory of the Aerospace Engineering Department, Politecnico di Milano, since 1999. He is now assistant professor of aerodynamics, his main research topics belong to experimental fluid dynamics and applied mathematics.
Carlo Cassinelli: He received his MSc. degree in Aeronautical Engineering in 2008 from Politecnico di Milano. He worked in the second half of 2008 in the Aerodynamic Engineering Research Laboratory of Politecnico di Milano as research associate collaborating to the present work on bluff body aerodynamics. Then, he left Politecnico to join AgustaWestland where he is presently employed.
Giuseppe Gibertini: He received his MSc. degree in Aeronautical Engineering in 1987 from Politecnico di Milano. He received a post-graduate Diploma in Fluid Dynamics in 1988 at Von Karman Institute then he rejoined the Politecnico where he obtained the Ph.D in Aerospace Engineering in 1992 with a thesis on “Separated turbulent flows”. He is now assistant professor at Politecnico di Milano where he is in charge of the Experimental Fluid Dynamic course since 1999. His current main research interests are bluff bodies fluid dynamics and unsteady aeronautical aerodynamics.
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Auteri, F., Belan, M., Cassinelli, C. et al. Interacting wakes of two normal flat plates an investigation based on phase averaging of LDA signals. J Vis 12, 307–321 (2009). https://doi.org/10.1007/BF03181875
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DOI: https://doi.org/10.1007/BF03181875