---
_id: '422'
abstract:
- lang: eng
text: We show that a rather simple, steady modification of the streamwise velocity
profile in a pipe can lead to a complete collapse of turbulence and the flow fully
relaminarizes. Two different devices, a stationary obstacle (inset) and a device
which injects fluid through an annular gap close to the wall, are used to control
the flow. Both devices modify the streamwise velocity profile such that the flow
in the center of the pipe is decelerated and the flow in the near wall region
is accelerated. We present measurements with stereoscopic particle image velocimetry
to investigate and capture the development of the relaminarizing flow downstream
these devices and the specific circumstances responsible for relaminarization.
We find total relaminarization up to Reynolds numbers of 6000, where the skin
friction in the far downstream distance is reduced by a factor of 3.4 due to relaminarization.
In a smooth straight pipe the flow remains completely laminar downstream of the
control. Furthermore, we show that transient (temporary) relaminarization in a
spatially confined region right downstream the devices occurs also at much higher
Reynolds numbers, accompanied by a significant local skin friction drag reduction.
The underlying physical mechanism of relaminarization is attributed to a weakening
of the near-wall turbulence production cycle.
article_processing_charge: Yes (via OA deal)
author:
- first_name: Jakob
full_name: Kühnen, Jakob
id: 3A47AE32-F248-11E8-B48F-1D18A9856A87
last_name: Kühnen
orcid: 0000-0003-4312-0179
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Markus
full_name: Schaner, Markus
id: 316CE034-F248-11E8-B48F-1D18A9856A87
last_name: Schaner
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Kühnen J, Scarselli D, Schaner M, Hof B. Relaminarization by steady modification
of the streamwise velocity profile in a pipe. Flow Turbulence and Combustion.
2018;100(4):919-942. doi:10.1007/s10494-018-9896-4
apa: Kühnen, J., Scarselli, D., Schaner, M., & Hof, B. (2018). Relaminarization
by steady modification of the streamwise velocity profile in a pipe. Flow Turbulence
and Combustion. Springer. https://doi.org/10.1007/s10494-018-9896-4
chicago: Kühnen, Jakob, Davide Scarselli, Markus Schaner, and Björn Hof. “Relaminarization
by Steady Modification of the Streamwise Velocity Profile in a Pipe.” Flow
Turbulence and Combustion. Springer, 2018. https://doi.org/10.1007/s10494-018-9896-4.
ieee: J. Kühnen, D. Scarselli, M. Schaner, and B. Hof, “Relaminarization by steady
modification of the streamwise velocity profile in a pipe,” Flow Turbulence
and Combustion, vol. 100, no. 4. Springer, pp. 919–942, 2018.
ista: Kühnen J, Scarselli D, Schaner M, Hof B. 2018. Relaminarization by steady
modification of the streamwise velocity profile in a pipe. Flow Turbulence and
Combustion. 100(4), 919–942.
mla: Kühnen, Jakob, et al. “Relaminarization by Steady Modification of the Streamwise
Velocity Profile in a Pipe.” Flow Turbulence and Combustion, vol. 100,
no. 4, Springer, 2018, pp. 919–42, doi:10.1007/s10494-018-9896-4.
short: J. Kühnen, D. Scarselli, M. Schaner, B. Hof, Flow Turbulence and Combustion
100 (2018) 919–942.
date_created: 2018-12-11T11:46:23Z
date_published: 2018-01-01T00:00:00Z
date_updated: 2024-03-28T23:30:36Z
day: '01'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1007/s10494-018-9896-4
ec_funded: 1
external_id:
isi:
- '000433113900004'
file:
- access_level: open_access
checksum: d7c0bade150faabca150b0a9986e60ca
content_type: application/pdf
creator: dernst
date_created: 2018-12-17T15:52:37Z
date_updated: 2020-07-14T12:46:25Z
file_id: '5717'
file_name: 2018_FlowTurbulenceCombust_Kuehnen.pdf
file_size: 2210020
relation: main_file
file_date_updated: 2020-07-14T12:46:25Z
has_accepted_license: '1'
intvolume: ' 100'
isi: 1
issue: '4'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: 919 - 942
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
publication: Flow Turbulence and Combustion
publication_status: published
publisher: Springer
publist_id: '7401'
quality_controlled: '1'
related_material:
record:
- id: '7258'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Relaminarization by steady modification of the streamwise velocity profile
in a pipe
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 100
year: '2018'
...