On two distinct Reynolds number regimes of a turbulent square jet
The effects of Reynolds number on both large-scale and small-scale turbulence properties are investigated in a square jet issuing from a square pipe. The detailed velocity fields were measured at five different exit Reynolds numbers of 8×103≤Re≤5×104. It is found that both large-scale properties (e....
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doaj-f2d7dc00033a4659b54d4a7f167b2b942020-11-24T23:14:27ZengElsevierTheoretical and Applied Mechanics Letters2095-03492015-05-015311712010.1016/j.taml.2015.04.001On two distinct Reynolds number regimes of a turbulent square jetMinyi Xu0Jianpeng Zhang1Pengfei Li2Jianchun Mi3Marine Engineering College, Dalian Maritime University, Dalian 116026, ChinaState Key Laboratory of Turbulence & Complex Systems, College of Engineering, Peking University, Beijing 100871, ChinaState Key Laboratory of Turbulence & Complex Systems, College of Engineering, Peking University, Beijing 100871, ChinaState Key Laboratory of Turbulence & Complex Systems, College of Engineering, Peking University, Beijing 100871, ChinaThe effects of Reynolds number on both large-scale and small-scale turbulence properties are investigated in a square jet issuing from a square pipe. The detailed velocity fields were measured at five different exit Reynolds numbers of 8×103≤Re≤5×104. It is found that both large-scale properties (e.g., rates of mean velocity decay and spread) and small-scale properties (e.g., the dimensionless dissipation rate constant A=εL/〈u2〉3/2) are dependent on Re for Re≤3×104 or Reλ≤190, but virtually become Re-independent with increasing Re or Reλ. In addition, for Reλ>190, the value of A=εL/〈u2〉3/2 in the present square jet converges to 0.5, which is consistent with the observation in direct numerical simulations of box turbulence, but lower than that in circular jet, plate wake flows, and grid turbulence. The discrepancies in critical Reynolds number and A=εL/〈u2〉3/2 among different turbulent flows most likely result from the flow type and initial conditions.http://www.sciencedirect.com/science/article/pii/S2095034915000392Square jetHot-wireReynolds numberSmall-scale turbulenceMean energy dissipation rate |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Minyi Xu Jianpeng Zhang Pengfei Li Jianchun Mi |
spellingShingle |
Minyi Xu Jianpeng Zhang Pengfei Li Jianchun Mi On two distinct Reynolds number regimes of a turbulent square jet Theoretical and Applied Mechanics Letters Square jet Hot-wire Reynolds number Small-scale turbulence Mean energy dissipation rate |
author_facet |
Minyi Xu Jianpeng Zhang Pengfei Li Jianchun Mi |
author_sort |
Minyi Xu |
title |
On two distinct Reynolds number regimes of a turbulent square jet |
title_short |
On two distinct Reynolds number regimes of a turbulent square jet |
title_full |
On two distinct Reynolds number regimes of a turbulent square jet |
title_fullStr |
On two distinct Reynolds number regimes of a turbulent square jet |
title_full_unstemmed |
On two distinct Reynolds number regimes of a turbulent square jet |
title_sort |
on two distinct reynolds number regimes of a turbulent square jet |
publisher |
Elsevier |
series |
Theoretical and Applied Mechanics Letters |
issn |
2095-0349 |
publishDate |
2015-05-01 |
description |
The effects of Reynolds number on both large-scale and small-scale turbulence properties are investigated in a square jet issuing from a square pipe. The detailed velocity fields were measured at five different exit Reynolds numbers of 8×103≤Re≤5×104. It is found that both large-scale properties (e.g., rates of mean velocity decay and spread) and small-scale properties (e.g., the dimensionless dissipation rate constant A=εL/〈u2〉3/2) are dependent on Re for Re≤3×104 or Reλ≤190, but virtually become Re-independent with increasing Re or Reλ. In addition, for Reλ>190, the value of A=εL/〈u2〉3/2 in the present square jet converges to 0.5, which is consistent with the observation in direct numerical simulations of box turbulence, but lower than that in circular jet, plate wake flows, and grid turbulence. The discrepancies in critical Reynolds number and A=εL/〈u2〉3/2 among different turbulent flows most likely result from the flow type and initial conditions. |
topic |
Square jet Hot-wire Reynolds number Small-scale turbulence Mean energy dissipation rate |
url |
http://www.sciencedirect.com/science/article/pii/S2095034915000392 |
work_keys_str_mv |
AT minyixu ontwodistinctreynoldsnumberregimesofaturbulentsquarejet AT jianpengzhang ontwodistinctreynoldsnumberregimesofaturbulentsquarejet AT pengfeili ontwodistinctreynoldsnumberregimesofaturbulentsquarejet AT jianchunmi ontwodistinctreynoldsnumberregimesofaturbulentsquarejet |
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1725594398408835072 |