## Abstract

This study focuses on the distribution of time scales and its relation to integral time scales in non-Gaussian turbulence within plant canopies. We introduce the idea of persistence usually used to describe nonequilibrium systems to the analysis of time series of turbulence as a simple approach to characterize the distribution of time scales. Analysis of turbulence data within and above a cornfield shows that the integral time scale is not adequate to characterize the duration of long events in non-Gaussian turbulence. Positive and negative events have different time scales as a consequence of the skewness of the velocity fluctuations. Sweeps (u' > 0 and w' < 0) are stronger and have shorter durations, and dominate the behavior of the integral time scale. At the same time, ejections (u' < 0 and w' > 0) tend to be much longer lived, and their signature (which is not clearly seen in the integral time scale) is clearly identified in the distributions of persistence time.

Original language | English (US) |
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Article number | 115110 |

Journal | Physics of Fluids |

Volume | 25 |

Issue number | 11 |

DOIs | |

State | Published - Aug 30 2013 |

## All Science Journal Classification (ASJC) codes

- Computational Mechanics
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Fluid Flow and Transfer Processes