TY - JOUR
T1 - Suboptimal control for drag reduction via suppression of near-wall Reynolds shear stress
AU - Fukagata, Koji
AU - Kasagi, Nobuhide
N1 - Funding Information:
This work was supported through the Project for Organized Research Combination System by the Ministry of Education, Culture, Sports and Technology of Japan (MEXT).
PY - 2004/6
Y1 - 2004/6
N2 - We propose a new suboptimal control law for drag reduction in wall-turbulence, which requires the streamwise wall-shear signal only. The cost function is designed to reduce the near-wall Reynolds shear stress that is directly related to the turbulent skin friction drag. The suboptimal solution to minimize the cost function is analytically derived by using the procedure proposed by Lee et al. [J. Fluid Mech. 358 (1998) 245]. Direct numerical simulation of turbulent pipe flow shows that the friction drag can be successfully reduced by the derived control law. Moreover, the sign of Reynolds shear stress in the near-wall layer is found to be reversed with the present control.
AB - We propose a new suboptimal control law for drag reduction in wall-turbulence, which requires the streamwise wall-shear signal only. The cost function is designed to reduce the near-wall Reynolds shear stress that is directly related to the turbulent skin friction drag. The suboptimal solution to minimize the cost function is analytically derived by using the procedure proposed by Lee et al. [J. Fluid Mech. 358 (1998) 245]. Direct numerical simulation of turbulent pipe flow shows that the friction drag can be successfully reduced by the derived control law. Moreover, the sign of Reynolds shear stress in the near-wall layer is found to be reversed with the present control.
KW - Control
KW - Control theory
KW - Direct numerical simulation
KW - Drag reduction
KW - Reynolds shear stress
KW - Turbulence
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U2 - 10.1016/j.ijheatfluidflow.2004.02.015
DO - 10.1016/j.ijheatfluidflow.2004.02.015
M3 - Article
AN - SCOPUS:2542604545
SN - 0142-727X
VL - 25
SP - 341
EP - 350
JO - International Journal of Heat and Fluid Flow
JF - International Journal of Heat and Fluid Flow
IS - 3
ER -