ISSN Online: 2688-7231
ISBN Online: 978-1-56700-524-0
Proceedings of the 26thNational and 4th International ISHMT-ASTFE Heat and Mass Transfer Conference December 17-20, 2021, IIT Madras, Chennai-600036, Tamil Nadu, India
Characteristics of laminar-turbulent bands in plane Couette flow
In plane Couette flow (pCf), the transitional regime is
characterized by oblique laminar-turbulent bands. These large scale patterns are periodic in both streamwise and spanwise directions. In this study, we perform direct numerical simulations (DNS) of pCf undergoing a reverse transition to understand the characteristics of the laminarturbulent bands. The large scale flow vectors near the bands are almost parallel to them due to a considerable spanwise velocity. Transitional pCf is different from its fully turbulent counterpart in certain aspects. Unlike fully turbulent flow, counter-rotating secondary roll cells are absent in the transitional regime. Another major difference is the presence of non-zero off-diagonal components of Reynolds stress tensor in transitional pCf.