ausblenden:
Schlagwörter:
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Zusammenfassung:
The turbulent kinetic energy dissipation rate is one
of the most important quantities characterizing turbulence.
Experimental studies of a turbulent flow in terms of the en-
ergy dissipation rate often rely on one-dimensional measure-
ments of the flow velocity fluctuations in time. In this work,
we first use direct numerical simulation of stationary homo-
geneous isotropic turbulence at Taylor-scale Reynolds num-
bers 74 ≤ Rλ ≤ 321 to evaluate different methods for infer-
ring the energy dissipation rate from one-dimensional veloc-
ity time records. We systematically investigate the influence
of the finite turbulence intensity and the misalignment be-
tween the mean flow direction and the measurement probe,
and we derive analytical expressions for the errors associ-
ated with these parameters. We further investigate how sta-
tistical averaging for different time windows affects the re-
sults as a function of Rλ. The results are then combined with
Max Planck Variable Density Turbulence Tunnel hot-wire
measurements at 147 ≤ Rλ ≤ 5864 to investigate flow condi-
tions similar to those in the atmospheric boundary layer. Fi-
nally, practical guidelines for estimating the energy dissipa-
tion rate from one-dimensional atmospheric velocity records
are given.
