Experiments on Taylor-Couette flow are performed when the working fluid (water) is stably stratified with salt. Depending on the rotation speeds and directions of inner and outer cylinders, different types of instability are observed and the path to turbulence is diverse.
1. Stratorotational instability (SRI)
2. Centrifugal instability (CI)
3. Mixed instabilities (SRI + CI)
Laminar-turbulent transition in supersonic boundary layers is studied by means of direct numerical simulation (DNS). At inflow, disturbance composed of instability waves enters a boundary layer at Mach number 1.6.
Streamwise velocity perturbation u'
Total temperature T
Large-eddy simulations of urban flows over a real urban area (Gangnam, Seoul, South Korea) show turbulent vortex shedding behind high-rise buildings.
This is the main work presented in doctoral thesis by Dr B.-S. Han at Seoul National University.
See also Han et al. (2018, QJRMS) for more details.