HIGH-RESOLUTION NUMERICAL ANALYSIS OF TURBULENT FLOW IN STRAIGHT OPEN DUCTS WITH RECTANGULAR CROSS-SECTION etc15 Tracking Number 219Presentation: Session: Vortex Dynamics 2 Room: Room B Session start: 15:00 Tue 25 Aug 2015 Yoshiyuki Sakai yoshiyuki.sakai@kit.edu Affifliation: Institute for Hydromechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany Markus Uhlmann markus.uhlmann@kit.edu Affifliation: Institute for Hydromechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany Genta Kawahara kawahara@me.es.osaka-u.ac.jp Affifliation: Department of Mechanical Science and Bioengineering, Osaka University, Toyonaka, Japan Topics: - Vortex dynamics and structure formation, - Wall bounded flows Abstract: Turbulent secondary flow in straight open ducts with rectangular cross-section are studied numerically by means of pseudo- spectral direct numerical simulation (DNS). Similarly to the corresponding closed duct flows, the mean streamwise vorticity pattern in turbulent open duct flows were found to be the statistical footprint of the most probable locations of the quasi-streamwise vortices. A major difference between the two configurations was found in the vicinity of mixed-boundary corners where noticeably persistent vortical structures exist.Turbulent secondary flow in straight open ducts with rectangular cross-section are studied numerically by means of pseudo- spectral direct numerical simulation (DNS). Similarly to the corresponding closed duct flows, the mean streamwise vorticity pattern in turbulent open duct flows were found to be the statistical footprint of the most probable locations of the quasi-streamwise vortices. A major difference between the two configurations was found in the vicinity of mixed-boundary corners where noticeably persistent vortical structures exist. |