TY - GEN
T1 - Spatially-localized optimal control of transition to turbulence
AU - Moarref, Rashad
AU - Lieu, Binh K.
AU - Jovanović, Mihailo R.
PY - 2011
Y1 - 2011
N2 - For the problem of controlling the onset of turbulence in a channel flow, we study the design of localized optimal state-feedback controllers. The actuation is generated by blowing and suction at the walls and we assume that the actuators are placed along a two-dimensional lattice of equally spaced points, and that each actuator uses information from only a limited number of nearby neighbors. We utilize recently developed tools for designing structured optimal feedback gains to reduce variance amplification of velocity fluctuations in the presence of flow disturbances. Our high-fidelity simulations of nonlinear flow dynamics, conducted at low Reynolds numbers, show that this approach can indeed maintain the laminar flow. This is in contrast to the localized strategies obtained by spatial truncation of optimal centralized controllers, which may introduce instability and promote transition even in the situations where the uncontrolled flow stays laminar.
AB - For the problem of controlling the onset of turbulence in a channel flow, we study the design of localized optimal state-feedback controllers. The actuation is generated by blowing and suction at the walls and we assume that the actuators are placed along a two-dimensional lattice of equally spaced points, and that each actuator uses information from only a limited number of nearby neighbors. We utilize recently developed tools for designing structured optimal feedback gains to reduce variance amplification of velocity fluctuations in the presence of flow disturbances. Our high-fidelity simulations of nonlinear flow dynamics, conducted at low Reynolds numbers, show that this approach can indeed maintain the laminar flow. This is in contrast to the localized strategies obtained by spatial truncation of optimal centralized controllers, which may introduce instability and promote transition even in the situations where the uncontrolled flow stays laminar.
KW - Flow control
KW - Navier-Stokes equations
KW - direct numerical simulations
KW - structured optimal control
KW - transition to turbulence
UR - http://www.scopus.com/inward/record.url?scp=80053141594&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80053141594&partnerID=8YFLogxK
U2 - 10.1109/acc.2011.5991032
DO - 10.1109/acc.2011.5991032
M3 - Conference contribution
AN - SCOPUS:80053141594
SN - 9781457700804
T3 - Proceedings of the American Control Conference
SP - 3577
EP - 3582
BT - Proceedings of the 2011 American Control Conference, ACC 2011
PB - Institute of Electrical and Electronics Engineers Inc.
ER -