ISSN Online: 2377-424X
ISBN Print: 0-89116-909-1
International Heat Transfer Conference 9
INFLUENCE OF DENSITY VARIATIONS ON SMALL TURBULENT STRUCTURES OF TEMPERATURE IN STRONGLY HEATED FLOWS
Abstract
Using conventional average, a first order series expansion on pressure fluctuations is applied on the formulation of the set of equations governing the turbulent motion of variable density nonchemically-reacting perfect gas. Equations for velocity and temperature fluctuations are given putting forward the fluid dilatation effect on turbulence, including buoyancy. A Fourier transform of these equations is made in application to the local isotropy wave number range of the turbulent velocity and temperature structures. Density variation effects appear to be mainly significative on temperature field. A spectral transfer model is used for quantitative analysis: in the general case of established turbulence the -5/3 law of the temperature turbulence spectra inertial range is replaced by a -1 law.