Characteristics and survival rate of a turbulent puff depending on the genration process(Fostering Joint International Research)

2017 Fiscal Year Final Research Report

• Project/Area Number: 15KK0219
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Fluid engineering
• Research Institution: Hokkaido University
• Principal Investigator: Tasaka Yuji 北海道大学, 工学研究院, 准教授 (00419946)
• Research Collaborator: ECKERT Sven Helmoholtz Zentrum Dresden-Rossendorf(HZDR), Group of Magnetohydrodynamics, Director ; PEIXINHO Jorge Université du Havre, Laboratoire Ondes et Milieux complexes, CNRS 1^[st] class researcher
• Project Period (FY): 2016 – 2017
• Keywords: 乱流遷移 / 渦列 / 孤立乱流塊

Outline of Final Research Achievements

Influences of hair-pin vortex street generated by a synthetic-jet actuator on creations of a turbulent puff in a pipe flow was investigated. The vortex street enhances the creation of puffs, but too much number of the hair-pins prevent growth of puffs and provide relaminarization. Further application of SJA on a local turbulence in flows through a sudden expansion of a pipe indicated that oscillatory perturbation provides different transition process to create the turbulence in comparison with standard, continuous-jet-type perturbations.

Free Research Field

流体力学