Numerical study of separated boundary layer transition under pressure gradient
Conference paper
Authors | Yang, Z. |
---|---|
Type | Conference paper |
Abstract | Large-eddy simulation (LES) is conducted to study the transition process of a separated boundary layer on a flat plate with an elliptical leading edge. A streamwise pressure distribution is imposed and the free stream turbulence intensity is 3% to mimic the suction surface of a low-pressure turbine (LPT) blade. A dynamic sub-grid scale model is employed in the study and the current LES results compare well with available experimental data and previous LES results. The transition process has been analysed with a particular focus on primary instabilities at work. Streaky structures further upstream of the separation, known as the Klebanoff Streaks, have been observed. Typical two-dimensional Kelvin-Helmholtz (K-H) rolls are distorted in the separated region. When Klebanoff streaks passing over a full-span K-H roll, portion of the two-dimensional roll merges with the Klebanoff streaks and develop into chaotic three-dimensional structures, whereas the remaining undisrupted two-dimensional K-H rolls develop into Λ-vortex indicating that despite the disturbances before separation, the K-H instability may still be the main instability at work. |
Keywords | Separated boundary layer; Transition |
Year | 2016 |
Journal | Proceedings of the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics |
Web address (URL) | http://hdl.handle.net/10545/620617 |
http://creativecommons.org/licenses/by-nc-nd/4.0/ | |
hdl:10545/620617 | |
File | File Access Level Open |
File | File Access Level Open |
File | File Access Level Open |
Publication dates | Jul 2016 |
Publication process dates | |
Deposited | 17 Oct 2016, 13:17 |
Contributors | University of Sussex, Brighton, UK and University of Derby, Derby, UK |
https://repository.derby.ac.uk/item/92xvz/numerical-study-of-separated-boundary-layer-transition-under-pressure-gradient
Download files
File
Numerical Study of Separated Boundary Layer Transition_2016.pdf | ||
File access level: Open |
license_url | ||
File access level: Open |
license.txt | ||
File access level: Open |
42
total views21
total downloads0
views this month0
downloads this month