R. A. Antonia

Abstract: All three components of the vorticity fluctuation have been measured simultaneously in a turbulent wake using a new eight-sensor vorticity probe. The vorticity fluctuation spectra agree reasonably well with those from a direct numerical simulation of a turbulent channel flow at high wavenumbers. The similarity between the instantaneous energy dissipation rate e and the instantaneous enstrophy ω2 is examined using spectra and probability density functions. The correlation between ω2 and e is evaluated in some detail. The homogeneous value of e is strongly correlated with ω2. The full value of e and, more especially its isotropic value, are less well correlated with the enstrophy. Conditional averaging indicates that high enstrophy regions are associated with high energy dissipation rate regions.

TL;DR: In this article, the mean dissipation rate of the temperature variance is measured on the axis of a heated turbulent round jet using a constant current anemometer (CCA) operating fine Pt-10%Rh wires at very low overheat.

TL;DR: In this article, the validity of velocity and scalar invariants in slightly heated and approximately isotropic turbulence generated by passive conventional grids is examined in the context of published data for both passive and active grids.

TL;DR: In this article, it was shown that the equilibrium similarity of the terms in the scale-by-scale (s-b-s) budget of the turbulent energy q2¯ is reasonably well approximated on the axis of the intermediate wake of a circular cylinder.

TL;DR: In this paper, the similarity between the temperature spectrum and the spectrum corresponding to the mean turbulent energy in a wide variety of turbulent (shear) flows is re-examined within the framework of second-order velocity and temperature structure functions.