Analysis of flow structure
Fluid motions are used to be complex as a result of instability and turbulence. However, in the statistical sense, the fluid motion has a particular pattern, consists of the small- and large-scale motions. Investigation of the pattern itself (i.e., flow structure) and the relationship to the flow statistics is important to improve the modeling of the nonlinear flow behavior and to understand the nature. To simplify the information in the flow fields, the algorithm for detecting the large-scale motions is devised.
Analysis of flow structures
Detection of the large-scale structures in instantaneous turbulent flow fields
Development of the streak detection method to investigate the large-scale turbulent structures statistically
Identification of the structures in the 3-D instantaneous flow fields Turbulent/non-turbulent interface Large-scale coherence of velocity fluctuations, vorticity and/or the Reynolds stress
Tracking of the detected structures with time
Sorting of the detected structures by the spatial dimension
Related papers: Lee & Zaki (C&F 2018), Lee et al. (JFM 2014, PoF 2015), Hwang et al. (JFM 2016)
Detection of the turbulent/non-turbulent (T/NT) interface
Vorticity magnitude as a detector function
Normalization for the Reynolds-number independent detection
Related paper: Lee & Zaki (C&F 2018), Lee et al. (JFM 2017)