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Updated: Jan 17, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Experimental evidence for the continuous transition between elastic and elastoinertial turbulence
Yi-Bao Zhang1, Lu Li2, Yaning Fan1
1Department of Energy and Power Engineering, New Cornerstone Science Laboratory, Center for Combustion Energy, Key Laboratory for Thermal Science and Power Engineering of MoE, Tsinghua University, Beijing 100084, China.
Summary
Elastic turbulence (ET) and elastoinertial turbulence (EIT) in viscoelastic fluids are now shown to be connected via a continuous transition. Elasticity drives both instabilities, with inertia playing a secondary role, unifying our understanding of these unique flow states.
Area of Science:
- Fluid Dynamics
- Rheology
- Turbulence
Background:
- Viscoelastic fluids exhibit unique flow states: elastic turbulence (ET) and elastoinertial turbulence (EIT).
- The relationship between ET and EIT has been a long-standing controversy in fluid dynamics.
Purpose of the Study:
- To experimentally investigate the connection between elastic turbulence and elastoinertial turbulence.
- To elucidate the roles of elasticity and inertia in the transition between these turbulent states.
Main Methods:
- Experiments were conducted using Taylor-Couette flow with viscoelastic fluids.
- Quantified the influence of elasticity and inertia on flow stability and transition dynamics.
- Analyzed flow structures and energy spectra across different flow regimes.
Main Results:
- Provided experimental evidence for a continuous transition between ET and EIT.
- Demonstrated that elasticity is the primary driver for both elastic and elastoinertial instabilities.
- Showcased a unified critical condition for these instabilities, described by a single function.
- Observed seamless evolution of flow structures and energy spectra from ET to various EIT regimes.
Conclusions:
- The transition between elastic turbulence and elastoinertial turbulence is continuous.
- A unified framework explains the onset of instabilities in viscoelastic flows.
- Findings offer fundamental insights into turbulence in viscoelastic fluids with implications for drag reduction and polymer processing.
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