TY - JOUR

T1 - A reduced-order model of three-dimensional unsteady flow in a cavity based on the resolvent operator

AU - Gomez, F.

AU - Blackburn, H. M.

AU - Rudman, M.

AU - Sharma, A. S.

AU - McKeon, B. J.

PY - 2016

Y1 - 2016

N2 - A novel reduced-order model for time-varying nonlinear flows arising from a resolvent decomposition based on the time-mean flow is proposed. The inputs required for the model are the mean-flow field and a small set of velocity time-series data obtained at isolated measurement points, which are used to fix relevant frequencies, amplitudes and phases of a limited number of resolvent modes that, together with the mean flow, constitute the reduced-order model. The technique is applied to derive a model for the unsteady three-dimensional flow in a lid-driven cavity at a Reynolds number of 1200 that is based on the two-dimensional mean flow, three resolvent modes selected at the most active spanwise wave number, and either one or two velocity probe signals. The least-squares full-field error of the reconstructed velocity obtained using the model and two point velocity probes is of the order of 5 % of the lid velocity, and the dynamical behaviour of the reconstructed flow is qualitatively similar to that of the complete flow.

AB - A novel reduced-order model for time-varying nonlinear flows arising from a resolvent decomposition based on the time-mean flow is proposed. The inputs required for the model are the mean-flow field and a small set of velocity time-series data obtained at isolated measurement points, which are used to fix relevant frequencies, amplitudes and phases of a limited number of resolvent modes that, together with the mean flow, constitute the reduced-order model. The technique is applied to derive a model for the unsteady three-dimensional flow in a lid-driven cavity at a Reynolds number of 1200 that is based on the two-dimensional mean flow, three resolvent modes selected at the most active spanwise wave number, and either one or two velocity probe signals. The least-squares full-field error of the reconstructed velocity obtained using the model and two point velocity probes is of the order of 5 % of the lid velocity, and the dynamical behaviour of the reconstructed flow is qualitatively similar to that of the complete flow.

KW - Low-dimensional models

KW - Nonlinear dynamical systems

UR - https://www-scopus-com.ezproxy.lib.monash.edu.au/record/display.uri?eid=2-s2.0-84973866276&origin=resultslist&sort=plf-f&src=s&st1=++A+reduced-order+model+of+three-dimensional+unsteady+flow+in+a+cavity+based+on+the+resolvent+operator&st2=&sid=69C6A3FEA18A92A1D2CFE2FBE4C407D7.f594dyPDCy4K3aQHRor6A%3a810&sot=b&sdt=b&sl=117&s=TITLE-ABS-KEY%28++A+reduced-order+model+of+three-dimensional+unsteady+flow+in+a+cavity+based+on+the+resolvent+operator%29&relpos=0&citeCnt=0&searchTerm=

U2 - 10.1017/jfm.2016.339

DO - 10.1017/jfm.2016.339

M3 - Article

AN - SCOPUS:84973866276

VL - 798

SP - R2-1-R2-14

JO - Journal of Fluid Mechanics

JF - Journal of Fluid Mechanics

SN - 0022-1120

ER -