TY - CONF
T1 - FEEDBACK CONTROL EFFECT IN TURBULENT CHANNEL FLOW WITH A BUMP BY MEANS OF DIRECT NUMERICAL SIMULATION
AU - Okochi, Yusuke
AU - Nabae, Yusuke
AU - Fukagata, Koji
N1 - Funding Information:
Authors are grateful to Drs S. Obi, K. Ando, and T. Kawata (Keio University) for fruitful discussions. This work was supported through JSPS KAKENHI grant No. 18H03758 and 21H05007 by Japan Society for the Promotion of Science.
Publisher Copyright:
© 2022 12th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2022. All rights reserved.
PY - 2022
Y1 - 2022
N2 - We investigate the effect of feedback control in a turbulent channel flow with a bump by means of direct numerical simulation (DNS). In this study, the opposition control proposed by Choi et al. (1994), which is the simplest feedback control method, is applied and the detection plane is set at about 15 wall units from the wall. Two bulk Reynolds numbers, Reb = 5600 and 12600, and two different bump heights, h+ ≈ 20 and 40, are considered. According to the DNS results, although the pressure drag is hardly changed, the total drag is decreased due to reduction of the friction drag in both cases of h+ ≈ 20 and 40. In addition, the control effect decreases as the bump height increases due to enhancement of the flow separation. The control effect decreases also as the Reynolds number increases.
AB - We investigate the effect of feedback control in a turbulent channel flow with a bump by means of direct numerical simulation (DNS). In this study, the opposition control proposed by Choi et al. (1994), which is the simplest feedback control method, is applied and the detection plane is set at about 15 wall units from the wall. Two bulk Reynolds numbers, Reb = 5600 and 12600, and two different bump heights, h+ ≈ 20 and 40, are considered. According to the DNS results, although the pressure drag is hardly changed, the total drag is decreased due to reduction of the friction drag in both cases of h+ ≈ 20 and 40. In addition, the control effect decreases as the bump height increases due to enhancement of the flow separation. The control effect decreases also as the Reynolds number increases.
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M3 - Paper
AN - SCOPUS:85143818770
T2 - 12th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2022
Y2 - 19 July 2022 through 22 July 2022
ER -