TY - GEN
T1 - Hybrid RANS/LES simulations of turbulent channel flow
AU - Gross, A.
AU - Fasel, H. F.
PY - 2009
Y1 - 2009
N2 - For the simulations discussed in this paper two geometries are considered: A square-duct channel flow at a Reynolds number based on bulk velocity and hydraulic diameter of 10,000 (627 based on friction velocity and hydraulic diameter) and a 1:3.33 rectangular channel flow at a Reynolds number based on bulk velocity and channel height of 10,000 (909 based on friction velocity and hydraulic diameter). Reynolds-averaged Navier-Stokes (RANS) and hybrid turbulence model simulations based on the flow simulation methodology (FSM), filter-based RANS, and partially-averaged Navier-Stokes simulations were carried out. In addition, for the square-duct flow, as a reference, we also carried out direct numerical simulations (DNS). A new FSM contribution function is proposed and tested. It is also shown how hybrid RANS/LES models can be extended to allow for "turbulence seeding" ("backscatter") in regions of vanishing model contribution and energy transfer to the unresolved scales in regions with increasing model contribution. A comparison of the mean flow data obtained with the different methods for three different grid resolutions showed that FSM and filter-based RANS with variable filter width consistently yielded the best bulk velocity and velocity profile predictions. It remains to be investigated if these methods perform equally well for more complex flows, such as separated diffuser flows.
AB - For the simulations discussed in this paper two geometries are considered: A square-duct channel flow at a Reynolds number based on bulk velocity and hydraulic diameter of 10,000 (627 based on friction velocity and hydraulic diameter) and a 1:3.33 rectangular channel flow at a Reynolds number based on bulk velocity and channel height of 10,000 (909 based on friction velocity and hydraulic diameter). Reynolds-averaged Navier-Stokes (RANS) and hybrid turbulence model simulations based on the flow simulation methodology (FSM), filter-based RANS, and partially-averaged Navier-Stokes simulations were carried out. In addition, for the square-duct flow, as a reference, we also carried out direct numerical simulations (DNS). A new FSM contribution function is proposed and tested. It is also shown how hybrid RANS/LES models can be extended to allow for "turbulence seeding" ("backscatter") in regions of vanishing model contribution and energy transfer to the unresolved scales in regions with increasing model contribution. A comparison of the mean flow data obtained with the different methods for three different grid resolutions showed that FSM and filter-based RANS with variable filter width consistently yielded the best bulk velocity and velocity profile predictions. It remains to be investigated if these methods perform equally well for more complex flows, such as separated diffuser flows.
UR - http://www.scopus.com/inward/record.url?scp=78549248512&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78549248512&partnerID=8YFLogxK
U2 - 10.2514/6.2009-1327
DO - 10.2514/6.2009-1327
M3 - Conference contribution
AN - SCOPUS:78549248512
SN - 9781563479694
T3 - 47th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition
BT - 47th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition
PB - American Institute of Aeronautics and Astronautics Inc.
ER -