Numerical implementation and evaluation of resolvent-based estimation for space-time energy spectra in turbulent channel flows  

作　　者：Bowen Yang Guodong Jin Ting Wu Zixuan Yang Guowei He 

机构地区：[1]State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China [2]School of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Acta Mechanica Sinica》2020年第4期775-788,共14页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Basic Science Center Program for“Multiscale Problems in Nonlinear Mechanics”)(Grant 11988102);The authors would like to thank the support from the Strategic Priority Research Program(Grant XDB22040104)。

摘　　要：Resolvent operator has been increasingly used to investigate turbulent flows and develop control strategies.Recently,Towne et al.(J Fluid Mech 883:A17,2020)proposed a resolvent-based estimation(RBE)method for predicting turbulent statistics in a channel flow.In this paper,we utilize the RBE method to predict the root-mean-square(RMS)and space-time energy spectra of streamwise velocity fluctuation,where the input is the space-time energy spectra at a reference horizontal plane located in the logarithmic layer and the output is the space-time energy spectra in the buffer layer.The explicit formulas for the RBE method are given in detail for numerical implementation.The results show the capability of the RBE method in the prediction of the convection velocity and bandwidth of the space-time energy spectra.Furthermore,we make a systematic evaluation of the performance of the RBE method by varying the input configurations,including the wall-normal location of the reference plane,the inclusion or exclusion of the pressure as an input variable,the implementation approach of the pressure boundary condition,and the choice of the window function.It is found that the results of both RMS velocity and space-time energy spectra obtained from the RBE method are sensitive to the location of the reference plane.However,the pressure boundary conditions and inclusion of pressure as an input do not cause significant change in the RMS velocity and space-time energy spectra.Although it does not influence the prediction of the RMS velocity,a window function is found crucial in the RBE method for the prediction of the space-time energy spectra.

关 键 词：Space-time energy spectra Turbulent channel flow Resolvent operator 

分 类 号：O357.5[理学—流体力学]