• Title/Summary/Keyword: Helical Wavy Vortex

Search Result 2, Processing Time 0.015 seconds

On the Structures of Taylor Vortices. (Taylor Vortex의 구조에 대한 연구)

  • Hwang, Jong-Yeon;Yang, Kyung-Soo
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.27 no.8
    • /
    • pp.1081-1088
    • /
    • 2003
  • Numerical investigation on the structures of various Taylor vortices induced in the flow between two concentric cylinders, with the inner one rotating and with a pressure-driven axial flow imposed, is carried out, and compared with the experiments of Wereley and Lueptow [Phys. fluid, 11(12), 1999] who studied the Taylor vortices using PIV in detail. Especially, the properties of helical vortices and random wavy vortices are discussed, and their three-dimensional structures are visualized using the numerical data. Our simulation also predicts that random wavy vortices have quasi-periodic movement which can be explained by traveling waves formed in the azimuthal direction. The numerical results are well consistent with the experimental findings of Wereley and Lueptow.

Axial Wall Slits Effect on the Helical Flow in the Gap between two Concentric Cylinders

  • Liu, Dong;Yang, Xiao-Yong;Ding, Jian;Kim, Hyoung-Bum
    • International Journal of Fluid Machinery and Systems
    • /
    • v.5 no.2
    • /
    • pp.60-64
    • /
    • 2012
  • The helical flow regime was investigated by using DPIV when the rotating Reynolds number is small. The wall slits were azimuthally located along the inner wall of outer cylinder and the slits number of each model was 9 and 18, another plain wall model was also studied for comparison purpose. The helical vortex flow regime can be observed in all the three models. The negative temperature gradients determine the direction of the rotation and movement of the helical vortex. But the helical wavy vortex flow can only be found in the plane and 9-slit models. And the result showed that the existence of slit wall accelerated the transition process.