---
_id: '7258'
abstract:
- lang: eng
text: Many flows encountered in nature and applications are characterized by a chaotic
motion known as turbulence. Turbulent flows generate intense friction with pipe
walls and are responsible for considerable amounts of energy losses at world scale.
The nature of turbulent friction and techniques aimed at reducing it have been
subject of extensive research over the last century, but no definite answer has
been found yet. In this thesis we show that in pipes at moderate turbulent Reynolds
numbers friction is better described by the power law first introduced by Blasius
and not by the Prandtl–von Kármán formula. At higher Reynolds numbers, large scale
motions gradually become more important in the flow and can be related to the
change in scaling of friction. Next, we present a series of new techniques that
can relaminarize turbulence by suppressing a key mechanism that regenerates it
at walls, the lift–up effect. In addition, we investigate the process of turbulence
decay in several experiments and discuss the drag reduction potential. Finally,
we examine the behavior of friction under pulsating conditions inspired by the
human heart cycle and we show that under such circumstances turbulent friction
can be reduced to produce energy savings.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
citation:
ama: Scarselli D. New approaches to reduce friction in turbulent pipe flow. 2020.
doi:10.15479/AT:ISTA:7258
apa: Scarselli, D. (2020). New approaches to reduce friction in turbulent pipe
flow. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:7258
chicago: Scarselli, Davide. “New Approaches to Reduce Friction in Turbulent Pipe
Flow.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:7258.
ieee: D. Scarselli, “New approaches to reduce friction in turbulent pipe flow,”
Institute of Science and Technology Austria, 2020.
ista: Scarselli D. 2020. New approaches to reduce friction in turbulent pipe flow.
Institute of Science and Technology Austria.
mla: Scarselli, Davide. New Approaches to Reduce Friction in Turbulent Pipe Flow.
Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:7258.
short: D. Scarselli, New Approaches to Reduce Friction in Turbulent Pipe Flow, Institute
of Science and Technology Austria, 2020.
date_created: 2020-01-12T16:07:26Z
date_published: 2020-01-13T00:00:00Z
date_updated: 2023-09-15T12:20:08Z
day: '13'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: BjHo
doi: 10.15479/AT:ISTA:7258
ec_funded: 1
file:
- access_level: closed
checksum: 4df1ab24e9896635106adde5a54615bf
content_type: application/zip
creator: dscarsel
date_created: 2020-01-12T15:57:14Z
date_updated: 2021-01-13T23:30:05Z
embargo_to: open_access
file_id: '7259'
file_name: 2020_Scarselli_Thesis.zip
file_size: 26640830
relation: source_file
- access_level: open_access
checksum: 48659ab98e3414293c7a721385c2fd1c
content_type: application/pdf
creator: dscarsel
date_created: 2020-01-12T15:56:14Z
date_updated: 2021-01-13T23:30:05Z
embargo: 2021-01-12
file_id: '7260'
file_name: 2020_Scarselli_Thesis.pdf
file_size: 8515844
relation: main_file
file_date_updated: 2021-01-13T23:30:05Z
has_accepted_license: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: None
page: '174'
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
- _id: 25136C54-B435-11E9-9278-68D0E5697425
grant_number: HO 4393/1-2
name: Experimental studies of the turbulence transition and transport processes
in turbulent Taylor-Couette currents
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '6228'
relation: part_of_dissertation
status: public
- id: '6486'
relation: part_of_dissertation
status: public
- id: '461'
relation: part_of_dissertation
status: public
- id: '422'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: New approaches to reduce friction in turbulent pipe flow
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '6228'
abstract:
- lang: eng
text: Following the recent observation that turbulent pipe flow can be relaminarised bya relatively simple modification of the mean velocity profile, we here carry out aquantitative experimental investigation of this phenomenon. Our study confirms thata flat velocity profile leads to a collapse of turbulence and in order to achieve theblunted profile shape, we employ a moving pipe segment that is briefly and rapidlyshifted in the streamwise direction. The relaminarisation threshold and the minimumshift length and speeds are determined as a function of Reynolds number. Althoughturbulence is still active after the acceleration phase, the modulated profile possessesa severely decreased lift-up potential as measured by transient growth. As shown,this results in an exponential decay of fluctuations and the flow relaminarises. Whilethis method can be easily applied at low to moderate flow speeds, the minimumstreamwise length over which the acceleration needs to act increases linearly with theReynolds number.
article_processing_charge: No
arxiv: 1
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Jakob
full_name: Kühnen, Jakob
id: 3A47AE32-F248-11E8-B48F-1D18A9856A87
last_name: Kühnen
orcid: 0000-0003-4312-0179
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Scarselli D, Kühnen J, Hof B. Relaminarising pipe flow by wall movement. Journal
of Fluid Mechanics. 2019;867:934-948. doi:10.1017/jfm.2019.191
apa: Scarselli, D., Kühnen, J., & Hof, B. (2019). Relaminarising pipe flow by
wall movement. Journal of Fluid Mechanics. Cambridge University Press.
https://doi.org/10.1017/jfm.2019.191
chicago: Scarselli, Davide, Jakob Kühnen, and Björn Hof. “Relaminarising Pipe Flow
by Wall Movement.” Journal of Fluid Mechanics. Cambridge University Press,
2019. https://doi.org/10.1017/jfm.2019.191.
ieee: D. Scarselli, J. Kühnen, and B. Hof, “Relaminarising pipe flow by wall movement,”
Journal of Fluid Mechanics, vol. 867. Cambridge University Press, pp. 934–948,
2019.
ista: Scarselli D, Kühnen J, Hof B. 2019. Relaminarising pipe flow by wall movement.
Journal of Fluid Mechanics. 867, 934–948.
mla: Scarselli, Davide, et al. “Relaminarising Pipe Flow by Wall Movement.” Journal
of Fluid Mechanics, vol. 867, Cambridge University Press, 2019, pp. 934–48,
doi:10.1017/jfm.2019.191.
short: D. Scarselli, J. Kühnen, B. Hof, Journal of Fluid Mechanics 867 (2019) 934–948.
date_created: 2019-04-07T21:59:14Z
date_published: 2019-05-25T00:00:00Z
date_updated: 2024-03-25T23:30:20Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2019.191
ec_funded: 1
external_id:
arxiv:
- '1807.05357'
isi:
- '000462606100001'
intvolume: ' 867'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1807.05357
month: '05'
oa: 1
oa_version: Preprint
page: 934-948
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- '14697645'
issn:
- '00221120'
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
link:
- relation: supplementary_material
url: https://doi.org/10.1017/jfm.2019.191
record:
- id: '7258'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Relaminarising pipe flow by wall movement
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 867
year: '2019'
...
---
_id: '461'
abstract:
- lang: eng
text: Turbulence is the major cause of friction losses in transport processes and
it is responsible for a drastic drag increase in flows over bounding surfaces.
While much effort is invested into developing ways to control and reduce turbulence
intensities, so far no methods exist to altogether eliminate turbulence if velocities
are sufficiently large. We demonstrate for pipe flow that appropriate distortions
to the velocity profile lead to a complete collapse of turbulence and subsequently
friction losses are reduced by as much as 90%. Counterintuitively, the return
to laminar motion is accomplished by initially increasing turbulence intensities
or by transiently amplifying wall shear. Since neither the Reynolds number nor
the shear stresses decrease (the latter often increase), these measures are not
indicative of turbulence collapse. Instead, an amplification mechanism measuring
the interaction between eddies and the mean shear is found to set a threshold
below which turbulence is suppressed beyond recovery.
acknowledgement: We acknowledge the European Research Council under the European Union’s
Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement 306589, the European
Research Council (ERC) under the European Union’s Horizon 2020 research and innovation
programme (grant agreement no. 737549) and the Deutsche Forschungsgemeinschaft (Project
No. FOR 1182) for financial support. We thank our technician P. Maier for providing
highly valuable ideas and greatly supporting us in all technical aspects. We thank
M. Schaner for technical drawings, construction and design. We thank M. Schwegel
for a Matlab code to post-process experimental data.
article_processing_charge: No
author:
- first_name: Jakob
full_name: Kühnen, Jakob
id: 3A47AE32-F248-11E8-B48F-1D18A9856A87
last_name: Kühnen
orcid: 0000-0003-4312-0179
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Ashley
full_name: Willis, Ashley
last_name: Willis
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
- 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, Song B, Scarselli D, et al. Destabilizing turbulence in pipe flow.
Nature Physics. 2018;14:386-390. doi:10.1038/s41567-017-0018-3
apa: Kühnen, J., Song, B., Scarselli, D., Budanur, N. B., Riedl, M., Willis, A.,
… Hof, B. (2018). Destabilizing turbulence in pipe flow. Nature Physics.
Nature Publishing Group. https://doi.org/10.1038/s41567-017-0018-3
chicago: Kühnen, Jakob, Baofang Song, Davide Scarselli, Nazmi B Budanur, Michael
Riedl, Ashley Willis, Marc Avila, and Björn Hof. “Destabilizing Turbulence in
Pipe Flow.” Nature Physics. Nature Publishing Group, 2018. https://doi.org/10.1038/s41567-017-0018-3.
ieee: J. Kühnen et al., “Destabilizing turbulence in pipe flow,” Nature
Physics, vol. 14. Nature Publishing Group, pp. 386–390, 2018.
ista: Kühnen J, Song B, Scarselli D, Budanur NB, Riedl M, Willis A, Avila M, Hof
B. 2018. Destabilizing turbulence in pipe flow. Nature Physics. 14, 386–390.
mla: Kühnen, Jakob, et al. “Destabilizing Turbulence in Pipe Flow.” Nature Physics,
vol. 14, Nature Publishing Group, 2018, pp. 386–90, doi:10.1038/s41567-017-0018-3.
short: J. Kühnen, B. Song, D. Scarselli, N.B. Budanur, M. Riedl, A. Willis, M. Avila,
B. Hof, Nature Physics 14 (2018) 386–390.
date_created: 2018-12-11T11:46:36Z
date_published: 2018-01-08T00:00:00Z
date_updated: 2024-03-25T23:30:20Z
day: '08'
department:
- _id: BjHo
doi: 10.1038/s41567-017-0018-3
ec_funded: 1
external_id:
isi:
- '000429434100020'
intvolume: ' 14'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1711.06543
month: '01'
oa: 1
oa_version: Preprint
page: 386-390
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
publication: Nature Physics
publication_status: published
publisher: Nature Publishing Group
publist_id: '7360'
quality_controlled: '1'
related_material:
record:
- id: '12726'
relation: dissertation_contains
status: public
- id: '14530'
relation: dissertation_contains
status: public
- id: '7258'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Destabilizing turbulence in pipe flow
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 14
year: '2018'
...