On the Laminar Separation of the Flow over a Backward Facing Step
Memoirs of the Faculty of Engineering, Yamaguchi University Volume 38 Issue 2
Page 203-211
published_at 1988
Title
後ろ向きステップの層流剥離に関する研究
On the Laminar Separation of the Flow over a Backward Facing Step
Creators
Nakanishi Suketsugu
Creators
Osaka Hideo
Source Identifiers
The flow over a backward facing step mounted in a two-dimensional channel was investigated numerically, and was especially examined for the zone of recirculating flow. A stream function-vorticity formulation for the flow equations was used, and was solved by the finite difference method using the pseudo-unsteady technique. The calculation was performed for the range of step Reynolds number (the Reynolds number based on the step height) of 25≦R_<eh>≦250,and for the range of step ratio of 0.1≦h_s≦1.0. The results of calculation are reported, and are compared with other numerical and experimental results. The present study also includes the experimental results utilizing the flow-visualization technique by the authors, and an example (R_<eh>=40) of those results is presented in this paper. Good agreement was obtained between the experimental and numerical results. In most of the available work, the step Reynolds number was used as a single parameter that defined the reattachment length (the length of recirculationg flow zone) in the laminar two-dimensional backward facing step flow. However, B. F. Armaly et al. (1983) suggested that the reattachment length in laminar two-dimensional backward facing step flow was not a function of a single variable but was more likely to be a function of three or more variables, including the step or expansion ratio, the step or inlet-section Reynolds number and the velocity profile at the inlet section. In this paper, this suggestion was examined by utilizing the numerical and experimental results.
Languages
jpn
Resource Type
departmental bulletin paper
Publishers
山口大学工学部
Date Issued
1988
File Version
Version of Record
Access Rights
open access
Relations
[ISSN]0372-7661
[NCID]AN00244228
Schools
工学部