Abstract
A methodology for the rapid determination of turbulent statistics is presented to enable the efficient non-intrusive evaluation of velocity profiles using a compact continuous-wave laser PIV system, particularly useful in cases where an experimental facility or model must be modified or repositioned in order to achieve a desired flow condition. In the present work this approach is used to guide the adjustment of a flexible roof in a large water tunnel in order to establish an ideally self-similar adverse pressure gradient turbulent boundary layer at the verge of separation. Following the feedback from real-time velocity statistics the height of the roof is adjust until a self-similar mean velocity profile was achieved while maintaining a small bias towards instantaneously attached flow. Initial results show an excellent collapse in the mean streamwise velocity profile over a extent of more than two boundary layer thickness with momentum thickness based Reynolds numbers ranging from Reδ2= 7500 to 8800, yet a trend of increasing peak Reynolds stress is observed with downstream position. Despite this trend the average profiles across this domain are in agreement with recent complementary direct numerical simulations
Original language | English |
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Title of host publication | Proceedings of the 18th International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics |
Subtitle of host publication | Lisbon, Portugal, July 4 - 7, 2016 |
Editors | D. F. G. Durão, K. Hishida, E. K. Longmire, A. L. Moreira, C. Tropea |
Publisher | Springer-Verlag London Ltd. |
Number of pages | 13 |
ISBN (Electronic) | 9789899877788 |
Publication status | Published - 2016 |
Event | International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics 2016 - The Calouste Gulbenkian Foundation, Lisbon, Portugal Duration: 4 Jul 2016 → 7 Jul 2016 Conference number: 18th http://ltces.dem.ist.utl.pt/lxlaser/lxlaser2016/ |
Conference
Conference | International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics 2016 |
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Country | Portugal |
City | Lisbon |
Period | 4/07/16 → 7/07/16 |
Other | often referred to simply as the "Lisbon Symposia |
Internet address |
Keywords
- PIV
- Turbulent boundary layers
- Adverse pressure gradient
- Separation
- Self-similarity