Partially-Averaged Navier-Stokes Simulation of the Flow Around Circular Cylinder at Re=3900: Comparison of Low and High Reynolds Number Approaches

Abstract

An appropriate choice of physical resolution for the Scale-Resolved Simulations (SRS) method is crucial for the accurate prediction of flow dynamics. The present study deals with numerical simulations of the flow past a circular cylinder using the Partially-Averaged Navier-Stokes bridging method. A subcritical Reynolds number 3900 is investigated at various physical resolution (the ratio of unresolved to total resolved turbulent kinetic energy f k) involving two approaches to estimate the ratio of unresolved to total resolved eddy dissipation rate fε, in particular a low Reynolds number fε = f k and a high Reynolds number fε = 1 approaches. Good agreement with experimental and DNS results was achieved for a higher physical resolution f k ≤ 0.5, fε = 1. The low Re approach led to the earlier transition of the separated boundary layer which resulted in a short recirculation region. Additionally, predicted results from simulations with the low Re approach were not influenced by a refinement of the computational grid.

Delayed Detached Eddy Simulation of Thermal Mixing in T-Junction

“…The velocity inlets were perturbed using the divergence-free synthetic eddy method [11]. This ensures that realistic inflow conditions are simulated, and eddies will not dissipate downstream the inlets [12,13]. Outlet condition was prescribed using constant pressure.…”

Numerical investigation of the effect of spanwise length and mesh density on flow around cylinder at Re = 3900 using LES model

“…The flow around a fixed cylinder at Re = 3900 come under the lower subcritical flow regime, which is highly sensitive in terms of flow separation, boundary layer nature, recirculation length, wake characteristics, and other hydrodynamic coefficients [3]. The availability of large-scale experimental and numerical data [4][5][6][7][8][9][10] for the flow around cylinders at Re = 3900 makes it an excellent benchmark case for assessing the capability of computational tools and process.…”

“…Korinek et al [7] used LES code and the Smagorinsky-Lilly subgrid-scale model to identify the effect of spanwise length and mesh resolution on measuring recirculation length and angle of separation around a fixed structure at Reynolds number = 3900. Most recently, Korinek et al [9] used partially average NS-bridging technique to investigate the flow over same Reynolds number at different ratio of resolved and unresolved turbulent kinetic energy. A shorter recirculation length is obtained at low Reynolds number due to earlier transition.…”