### Abstract

The pseudospectral method, in conjunction with a technique for obtaining scaling exponents

*ζ*from the structure functions_{n}*S*, is presented as an alternative to the extended self-similarity (ESS) method and the use of generalized structure functions. We propose plotting the ratio ∣∣_{n}(r)*S*∣∣ against the separation_{n}(r)/S_{3}(r)*r*in accordance with a standard technique for analyzing experimental data. This method differs from the ESS technique, which plots*S*against_{n}(r)*S*, with the assumption_{3}(r)*S*. Using our method for the particular case of_{3}(r)∼r*S*we obtain the result that the exponent_{2}(r)*ζ*decreases as the Taylor-Reynolds number increases, with_{2}*ζ*→ 0.679±0.013 as_{2}*R*→∞. This supports the idea of finite-viscosity corrections to the K41 prediction for_{λ}*S*, and is the opposite of the result obtained by ESS. The pseudospectral method also permits the forcing to be taken into account exactly through the calculation of the energy input in real space from the work spectrum of the stirring forces._{2}Original language | English |
---|---|

Article number | 053010 |

Number of pages | 12 |

Journal | Physical Review E |

Volume | 90 |

Issue number | 5 |

DOIs | |

Publication status | Published - 20 Nov 2014 |

### Fingerprint

### Keywords

- spectral analysis
- structure functions
- isotropic turbulence
- extended self-similarity
- ESS

### Cite this

McComb, W. D., Yoffe, S. R., Linkmann, M. F., & Berera, A. (2014). Spectral analysis of structure functions and their scaling exponents in forced isotropic turbulence.

*Physical Review E*,*90*(5), [053010]. https://doi.org/10.1103/PhysRevE.90.053010