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Published on: June 1, 2016
Conditional statistics of temperature fluctuations in turbulent convection
Summary
In turbulent convection, temperature differences become Gaussian when buoyancy drives mixing. Intermittency in these fluctuations arises from variations in the local temperature dissipation rate, clarifying temperature structure function behavior.
Area of Science:
- Physics
- Fluid Dynamics
- Turbulence Research
Background:
- Turbulent convection involves complex fluid mixing and temperature fluctuations.
- Understanding intermittency in temperature fluctuations is crucial for turbulence modeling.
- Previous models often struggle to explain the behavior of temperature structure functions.
Purpose of the Study:
- To investigate the statistical properties of temperature differences in turbulent convection.
- To determine the cause of intermittency in temperature fluctuations within buoyancy-driven regimes.
- To derive and analyze the functional behavior of conditional temperature structure functions.
Main Methods:
- Analysis of conditional statistics of temperature difference at fixed dissipation rates.
- Focus on the buoyancy-driven mixing regime in turbulent convection.
- Derivation of the functional form for conditional temperature structure functions.
Main Results:
- Conditional temperature difference statistics follow a Gaussian distribution in the buoyancy-driven regime.
- Intermittency is solely attributed to variations in the locally averaged temperature dissipation rate.
- A novel functional form for conditional temperature structure functions was obtained.
Conclusions:
- The study clarifies the origin of intermittency in turbulent convection temperature fluctuations.
- The derived functional form for temperature structure functions challenges existing dimensional arguments.
- This work enhances the fundamental understanding of temperature dynamics in turbulent flows.
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