Heavy inertial particles in turbulent flows gain energy slowly but lose it rapidly.

  title={Heavy inertial particles in turbulent flows gain energy slowly but lose it rapidly.},
  author={Akshay Bhatnagar and Anupam Gupta and Dhrubaditya Mitra and Rahul Pandit},
  journal={Physical review. E},
  volume={97 3-1},
We present an extensive numerical study of the time irreversibility of the dynamics of heavy inertial particles in three-dimensional, statistically homogeneous, and isotropic turbulent flows. We show that the probability density function (PDF) of the increment, W(τ), of a particle's energy over a time scale τ is non-Gaussian, and skewed toward negative values. This implies that, on average, particles gain energy over a period of time that is longer than the duration over which they lose energy… Expand
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