Skip to content
Longterm Wiki
Back

Mozannar et al. (2020)

paper

Authors

Cameron C. Hopkins·Simon J. Haward·Amy Q. Shen

Credibility Rating

3/5
Good(3)

Good quality. Reputable source with community review or editorial standards, but less rigorous than peer-reviewed venues.

Rating inherited from publication venue: arXiv

This appears to be a fluid dynamics paper on viscoelastic flows through porous media, unrelated to AI safety. Likely misclassified or requires verification of actual content relevance to AI safety research.

Paper Details

Citations
18
1 influential
Year
2020

Metadata

arxiv preprintprimary source

Abstract

Viscoelastic flows through microscale porous arrays exhibit complex path-selection and switching phenomena. However, understanding this process is limited by a lack of studies linking between a single object and large arrays. Here, we report experiments on viscoelastic flow past side-by-side microcylinders with variable intercylinder gap. With increasing flow rate, a sequence of two imperfect symmetry-breaking bifurcations forces selection of either one or two of the three possible flow paths around the cylinders. Tuning the gap length through the value where the first bifurcation becomes perfect reveals regions of bi and tristability in a dimensionless flow rate-gap length `phase' diagram.

Summary

This experimental study investigates viscoelastic flow behavior around side-by-side microcylinders with variable spacing. The research demonstrates that increasing flow rates trigger symmetry-breaking bifurcations that force the fluid to select specific flow paths around the cylinders. By systematically varying the gap between cylinders, the authors map regions of bistability and tristability in a phase diagram, providing insights into path-selection mechanisms in viscoelastic flows through microscale porous structures.

Cited by 1 page

PageTypeQuality
AI-Human Hybrid SystemsApproach91.0

Cached Content Preview

HTTP 200Fetched Mar 20, 202639 KB
# Tristability in viscoelastic flow past side-by-side microcylinders

Cameron C. Hopkins
Simon J. Haward
Amy Q. Shen
Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa, 904-0495, Japan

###### Abstract

Viscoelastic flows through microscale porous arrays exhibit complex path-selection and switching phenomena. However, understanding this process is limited by a lack of studies linking between a single object and large arrays. Here, we report experiments on viscoelastic flow past side-by-side microcylinders with variable intercylinder gap. With increasing flow rate, a sequence of two imperfect symmetry-breaking bifurcations forces selection of either one or two of the three possible flow paths around the cylinders. Tuning the gap length through the value where the first bifurcation becomes perfect reveals regions of bi and tristability in a dimensionless flow rate-gap length ‘phase’ diagram.

††preprint: APS/123-QED

Since the advent of microfluidics in the early 2000s \[ [1](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib1 ""), [2](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib2 "")\], geometries with length-scales ℓ∼O(100μ\\ell\\sim O(100~{}\\mum) have become a vital tool in experimental fluid dynamics. At the microscale, viscoelastic fluids (with properties between viscous liquids and elastic solids) can flow with negligible inertia (Reynolds number Re∼ℓ≪1similar-toReℓmuch-less-than1\\textnormal{Re}\\sim\\ell\\ll 1), but high elasticity (Weissenberg number Wi∼ℓ−1≫1similar-toWisuperscriptℓ1much-greater-than1\\textnormal{Wi}\\sim\\ell^{-1}\\gg 1) \[ [2](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib2 "")\]. In such flows, elasticity becomes the dominant source of nonlinearity, leading to instabilities \[ [3](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib3 ""), [4](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib4 ""), [5](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib5 ""), [6](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib6 ""), [7](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib7 ""), [8](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib8 ""), [9](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib9 "")\], and time-dependency that impact widespread processes ranging from jet fragmentation \[ [10](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib10 ""), [11](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib11 "")\] to hemodynamics \[ [12](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib12 ""), [13](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib13 "")\] and porous media flows \[ [14](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib14 ""), [15](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib15 ""), [16](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib16 ""), [17](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib17 ""), [18](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bib18 ""), [19](https://ar5iv.labs.arxiv.org/html/2010.14749#bib.bi

... (truncated, 39 KB total)
Resource ID: de7b0afb58582174 | Stable ID: ZDY5YWE0MW