Collapse of turbulence in optimised curved pipe flow

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Bagheri, Eman, Becker, Stefan, Schlatter, Philipp
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910164576108544
author Bagheri, Eman
Becker, Stefan
Schlatter, Philipp
author_facet Bagheri, Eman
Becker, Stefan
Schlatter, Philipp
contents The increased friction caused by turbulence is a significant contributor to energy consumption in the fluid-transport and piping industries. Here we describe a passive approach to reduce friction: we show that a local increase in streamwise flow curvature, combined with changing the circular cross-section to an oval, relaminarizes turbulent flow in curved pipes. We exemplify this effect in a $180^\circ$ bend at $Re_D = 10\,000$ and $20\,000$, well above the linear-stability limit. Curvature inhibits streamwise Reynolds stresses, and cross-sectional modifications weaken the secondary flow, together disrupting the near-wall regeneration cycle and collapsing turbulence. Simulations and experiments confirm that these geometric modifications suppress turbulence and reduce pressure loss by 53% and 36% compared with the baseline $180^\circ$ bend and an equal-length fully developed straight pipe, respectively. The results establish a passive, mechanism-based route to relaminarization in curved pipes with implications for energy-efficient control in other wall-bounded flows with curvature.
format Preprint
id arxiv_https___arxiv_org_abs_2511_17073
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Collapse of turbulence in optimised curved pipe flow
Bagheri, Eman
Becker, Stefan
Schlatter, Philipp
Fluid Dynamics
The increased friction caused by turbulence is a significant contributor to energy consumption in the fluid-transport and piping industries. Here we describe a passive approach to reduce friction: we show that a local increase in streamwise flow curvature, combined with changing the circular cross-section to an oval, relaminarizes turbulent flow in curved pipes. We exemplify this effect in a $180^\circ$ bend at $Re_D = 10\,000$ and $20\,000$, well above the linear-stability limit. Curvature inhibits streamwise Reynolds stresses, and cross-sectional modifications weaken the secondary flow, together disrupting the near-wall regeneration cycle and collapsing turbulence. Simulations and experiments confirm that these geometric modifications suppress turbulence and reduce pressure loss by 53% and 36% compared with the baseline $180^\circ$ bend and an equal-length fully developed straight pipe, respectively. The results establish a passive, mechanism-based route to relaminarization in curved pipes with implications for energy-efficient control in other wall-bounded flows with curvature.
title Collapse of turbulence in optimised curved pipe flow
topic Fluid Dynamics
url https://arxiv.org/abs/2511.17073