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Updated: Jun 19, 2026
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Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
Scaling and statistical geometry in passive scalar turbulence
Andrea Mazzino1, Paolo Muratore-Ginanneschi
1Department of Physics, University of Genova, INFN and CNISM, via Dodecaneso 33, 16146 Genova, Italy.
Summary
Turbulent passive scalar statistics at larger scales show multiscaling. This arises from a weaker mechanism than conservation laws, with explicit predictions for scaling exponents in the Kraichnan model.
Area of Science:
- Fluid dynamics
- Statistical physics
- Turbulence theory
Background:
- Turbulent passive scalars are crucial in various scientific fields.
- Understanding their statistical properties at different scales is a key challenge.
- Existing models often rely on statistical conservation laws to explain observed phenomena.
Purpose of the Study:
- To investigate the multiscaling behavior of turbulent passive scalars at scales larger than the pumping.
- To propose a new mechanism for multiscaling beyond statistical conservation laws.
- To develop a general formalism for predicting scaling exponents in the Kraichnan model.
Main Methods:
- Development of a general theoretical formalism.
- Analysis of the Kraichnan model for turbulent passive scalars.
- Investigation of scaling exponents at different scales.
Main Results:
- Demonstration of multiscaling in turbulent passive scalar statistics at larger scales.
- Identification of a weaker mechanism driving multiscaling compared to conservation laws.
- Explicit predictions for large-scale scaling exponents derived from the developed formalism.
Conclusions:
- Multiscaling in turbulent passive scalars can occur due to mechanisms other than statistical conservation laws.
- The developed formalism provides accurate predictions for scaling exponents.
- The geometric origin of multiscaling at both small and large scales is discussed.
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