ISSN:
1089-7666
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Velocity autocorrelations and the mean-square displacements of fluid particles are obtained for decaying, isotropic homogeneous turbulence by numerical simulation of the flow field, using 1283 and 2563 grids, and tracking several tens of thousands of fluid particles, using a third-order interpolation scheme. A self-preserving Lagrangian velocity autocorrelation coefficient is found in terms of a dimensionless time variable s, defined by ds=dt/Ts(t), under the observation of a power-law energy decay and the assumption that Ts(t) is proportional to the Lagrangian integral timescale TL. This timescale is in turn assumed to be proportional to the length scale of the energy-containing eddies Le∼K3/2/ε divided by the turbulent velocity u′, where K=3/2u′2 is turbulent energy and ε is the energy dissipation rate. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.868780
