Turbulent diffusion in a shearing oscillatory flow |
| |
Authors: | Zhang Fagao Takashi Ichiye |
| |
Institution: | (1) Institute of Oceanology, Academia Sinica, China;(2) Dept. of Oceanography, Texas A & M University, USA |
| |
Abstract: | The diffusion in a shearing oscillatory flow from an instantaneous surface point source is considered. An analytical solution
is obtained by Fourier transform. The results show that, for three dimensional diffusion in an oscillatory flow with constant
shear, the distribution of the contaminant follows the multivariate Gaussian distribution rule. When the frequency is very
high, or the time very short, the shear does not influence the diffusion. For moderate values of time, there are fluctuations
with longitudinal variance. For large values of time the longitudinal variance increases as t, and the peak concentration
decreases as t−1.5, which are faster than those in a flow without shear, but much slower than those in a steady flow, where the longitudinal
variance increases as t3 and the peak concentration decreases as t−2.5. The contaminant patch is elongated in the longitudinal direction of the shear flow and moves back and forth with the water
motion.
Contribution No. 1306 from the Institute of Oceanology, Academia Sinica. Received July 12, 1985 |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|