TY - JOUR
T1 - Scalar dissipation rate and dissipative anomaly in isotropic turbulence
AU - Donzis, D. A.
AU - Sreenivasan, K. R.
AU - Yeung, P. K.
PY - 2005/6/10
Y1 - 2005/6/10
N2 - We examine available data from experiment and recent numerical simulations to explore the supposition that the scalar dissipation rate in turbulence becomes independent of the fluid viscosity when the viscosity is small and of scalar diffusivity when the diffusivity is small. The data are interpreted in the context of semi-empirical spectral theory of Obukhov and Corrsin when the Schmidt number, Sc, is below unity, and of Batchelor's theory when Sc is above unity. Practical limits in terms of the Taylor-microscale Reynolds number, Rλ, as well as Sc, are deduced for scalar dissipation to become sensibly independent of molecular properties. In particular, we show that such an asymptotic state is reached if RλSc1/2 ≫ 1 for Sc < 1, and if ln(Sc)/Rλ ≫ 1 for Sc < 1.
AB - We examine available data from experiment and recent numerical simulations to explore the supposition that the scalar dissipation rate in turbulence becomes independent of the fluid viscosity when the viscosity is small and of scalar diffusivity when the diffusivity is small. The data are interpreted in the context of semi-empirical spectral theory of Obukhov and Corrsin when the Schmidt number, Sc, is below unity, and of Batchelor's theory when Sc is above unity. Practical limits in terms of the Taylor-microscale Reynolds number, Rλ, as well as Sc, are deduced for scalar dissipation to become sensibly independent of molecular properties. In particular, we show that such an asymptotic state is reached if RλSc1/2 ≫ 1 for Sc < 1, and if ln(Sc)/Rλ ≫ 1 for Sc < 1.
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U2 - 10.1017/S0022112005004039
DO - 10.1017/S0022112005004039
M3 - Article
AN - SCOPUS:21344464206
SN - 0022-1120
VL - 532
SP - 199
EP - 216
JO - Journal of Fluid Mechanics
JF - Journal of Fluid Mechanics
ER -