University of Illinois Urbana-Champaign

Stability and Vortex Shedding of Bluff Body Arrays

Parker, S.J.; Balachandar, S.

Content Files
TR189.pdf

Permalink

https://hdl.handle.net/2142/12042

Description

Title
Stability and Vortex Shedding of Bluff Body Arrays
Author(s)
  • Parker, S.J.
  • Balachandar, S.
Issue Date
2001-08
Keyword(s)
heat transfer enhancement
Date of Ingest
2009-06-04T21:16:16Z
Abstract
The primary purpose of this study was to develop an understanding of the stability of laminar flow through bluff body arrays, and investigate the nature of the unsteady vortex shedding regime that follows. The flow was numerically investigated using a specially developed multi-domain spectral element solver. Important criteria in the solver development were flexibility, efficiency, and accuracy. Flexibility was critical to the functionality of the code, as arrays of varying geometry were investigated. Efficiency with a high degree of accuracy was also of primary importance, with the code implemented to run efficiently on today's massively parallel architectures. Numerical two-dimensional stability analysis of the flow in several configurations of inline and staggered array geometries was performed. The growth rate, eigenfunction, and frequency of the disturbances were determined. The critical Reynolds number for flow transition in each case was identified and compared to that of flow over a single body. Based on the solutions of the laminar flow, a one-dimensional analytical analysis was performed on selected velocity profiles in the wake region. The results of this analysis were used to guide the interpretation of the two dimensional results and formulate a general theory of stability of inline and staggered bluff body arrays. The nature of the flow in the unsteady regime following the onset of instability was examined for an inline and a staggered arrangement. Particular attention was focused on the vortex shedding which was visualized and quantified through computation of the flow swirl, a quantity which identifies regions of rotary motion. The conditions required for the generation of leading edge vortex shedding were identified and discussed. Finally, a third geometry related to the inline and staggered arrays was considered. Flow solution data for this geometry is presented and its suitability as a model for louvered arrays was discussed.
Publisher
Air Conditioning and Refrigeration Center. College of Engineering. University of Illinois at Urbana-Champaign.
Series/Report Name or Number
Air Conditioning and Refrigeration Center TR-189
Type of Resource
text
Genre of Resource
Technical Report
Language
en
Permalink
http://hdl.handle.net/2142/12042
Sponsor(s)/Grant Number(s)
Air Conditioning and Refrigeration Project 112

Owning Collections

Technical Reports - Air Conditioning and Refrigeration Center PRIMARY