Abstract
Direct numerical simulation (DNS) is used to calculate the three-dimensional cases of elongated bluff body under low Reynolds numbers (Re=1000). Primary instabilities such as Von Karman vortices and secondary instabilities including Mode A and Mode C are identified in the numerical results to investigate the physical mechanism of the wake region. Besides, vortex formation length and wave length of secondary instabilities are also characterized to reveal the flow structures. In the cases where Re=1000, Mode A is the dominant secondary instability in RANS initialized calculation. The spanwise and streamwise wavelength of Mode A is about 3D and 4D respectively, where D is the thickness of trailing edge. The sense of rotation alternates every half shedding cycle, which exhibits out-phase symmetry. However, Mode A and Mode C coexist in free-stream-condition initialized calculation. The spanwise wavelength of Mode C is about 0.5D. Conclusion is reached that difference in initialization method may result in difference in wake flow instabilities.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
