Skin-friction critical points in wall-bounded flows

1st Multiflow Summer Workshop

Cardesa, José I.^1 ; Monty, Jason P.^2 ; Soria, Julio^3 ; Chong, Min S.^2

School of Aeronautics, Universidad Politécnica de Madrid, Madrid, Spain^1

Mechanical Engineering Department, University of Melbourne, VIC 3010, Australia^2

Mechanical Engineering Department, Monash University, VIC 3800, Australia^3

关键词: Area density;    Average Distance;    Conditional average;    Statistical descriptions;    Time sequences;    Wall bounded flows;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/506/1/012009/pdf
DOI  :  10.1088/1742-6596/506/1/012009

来源: IOP

【 摘 要 】

Critical points in the skin friction field of wall-bounded ows were investigated using data from direct numerical simulations of channels at Reτ = 934 and Reτ = 1834. A method for their detection and characterisation is outlined, and a statistical description of their properties is reported. Their lifetime, average distance, velocity and area density were computed. Conditionally averaged fields were calculated in order to examine the average ow in the vicinity of a critical point. It was found that the critical points are connected to surprisingly large features in the channel. A mechanism for the generation of the critical points is postulated, based on the conditional averages and analysis of time sequences in the ow above them.