Spectra of decaying scalar fluctuations in homogeneous isotropic turbulence

More recent measurements have shown that the degree of the decay of scalar fluctuations (respectively the exponent m) depends on the manner of generation. Experiments conducted by Warhaft and Lumley (1978) showed that growing values of m corresponded to an increasing displacement of the wave number k of the peak of the three-dimensional spectrum to larger wave numbers. It is shown that the displacement of the maximum is also a consequence of the similarity law of the scalar spectrum for the inertia convection range derived by Szablewski (1980). The obtained data are compared with the values measured by Warhaft and Lumley.