ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
This paper summarizes an experimental study of turbulent diffusion downstream of a line source of heat. Mean temperature profiles in the core of nearly fully developed pipe flow were measured at four mean velocities, from Uc = 72.6 to 160 ft./sec. Hot-wire anemometer surveys showed that the turbulence in the axial core was nearly homogeneous and isotropic. The objective was to find empirical relations between the anemometer (Eulerian) specification of the turbulence and the Lagrangian statistical properties which determine diffusion.The diffusion results agreed with predictions of G. I. Taylor's theory of diffusion by continuous movements; the eddy diffusivity increased from zero at the heat source to a constant, asymptotic value far downstream. The Lagrangian correlation coefficients inferred from the diffusion data had shapes similar to the Eulerian correlations over most of the range of time and space. Empirical relations were found to relate the coordinates of the Lagrangian and Eulerian correlation coefficients over the range of this experiment. In addition preliminary measurements are reported for a general Eulerian correlation which is a function of both space and time; the results indicate that a special case of this new Eulerian function may be a fair approximation of the Lagrangian correlation.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690070115
