ISSN:
1089-7666
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The spectrum of a passive temperature field, G(k), has been determined by a numerical simulation using three kinds of isotropic turbulent velocity fields. For a time independent and Gaussian velocity field, the resulting G(k) has the form G(k)=G0εθε2/3 χ−3k−17/3, with G0=0.33±0.02 Ko, confirming the prediction of Batchelor, Howells, and Townsend [J. Fluid Mech. 5, 134 (1959)]. For a velocity field developed through the Navier–Stokes equations and then frozen in time, G(k) has the same form as above, but with G0 =0.39±0.03 Ko. Finally, for a velocity field developed concurrently with the temperature field, G(k) collapses onto the spectrum obtained using a frozen, developed velocity field only for high enough values of the conductivity χ. For lower values of χ, the power law behavior of G(k) is less clear.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.867013
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