Blending and internal boundary-layer heights, and shear stress     

J.R. Philip 《Boundary-Layer Meteorology》1997,84(1):85-98

Previous studies of blending heightsfor scalars, using periodic solutions of atmosphericconvection-diffusion equations, raise two questions. 1. What is the relation between growth of the internalboundary-layer height downwind of a step in surfaceconditions, and the increase of blending height withdownwind pattern wavelength? 2. Can the approach beextended to shear stress? The answers are: 1. Thedependence of boundary-layer height on fetch has thesame functional form as that of blending height onwavelength; but it is greater by a factor of about1.9. 2. Representing eddy diffusivity as the productof mean windspeed and a power of height gives a linearhorizontal momentum equation. A further approximationgives a convection-diffusion equation for shearstress, analogous to those used previously forscalars.  相似文献   

Three-dimensional finite difference model for transport of conservative pollutants   总被引：1，自引：0，他引：1  

S. Sankaranarayanan  N.J. Shankar  H.F. Cheong 《Ocean Engineering》1998,25(6):425-442

A three-dimensional finite difference transport model appropriate for the coastal environment is developed for the solution of the three-dimensional convection-diffusion equation. A higher order upwind scheme is used for the convective terms of the convection-diffusion equation, to minimise the numerical diffusion. The validity of the numerical model is verified through five test problems, whose exact solutions are known.  相似文献