Abstract:
The flow field around the cylinder cascade is widely used to
analyze the interaction of vortex shedding and the information
on heat transfer. Large eddy simulation (LES) can be used to
get the turbulent flow information in detail. The resolved largescale
structures are determined by the size of the grid, and the
turbulent vortex dissipation is modeled with a subgrid scale
model. Whereas there is no accurate criterion to provide the
subgrid scale with the physical meaning. Based on turbulent
energy ratio coefficient and numerical simulation results with
turbulent model, the subgrid was generated for the
incompressible fluid flowing around a column of cylinder
cascade with a gap-to-diameter ratio of 2. Smagorinsky-Lily
(SM) model was applied to LES analysis. The turbulent flow
information was compared with the experimental data by PIV.
Two cases with different Reynolds numbers were studied.
When the turbulent energy ratio coefficient reached to 30%-
40%, the turbulent dissipation could be captured by LES
method with less grid number. The large scale vortex
interaction behind the cylinder cascade was analyzed further. It
is verified that LES method can be used for engineering based
on the turbulent energy ratio coefficient with acceptable
computational cost.
Description:
papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.