A SmallScale Dynamic Model Using a TerrainFollowing Coordinate Transformation
Abstract
This paper describes a threedimensional finitedifference model of air flow over an irregular lower surface. The model is nonhydrostatic and the anelastic approximation has been used to filter sound waves. Secondorder difference equations are employed which provide excellent momentum and energy budgets. An outflow radiation boundary condition using a generalized Kreiss extrapolation scheme has been designed and implemented. Some twodimensional applications of the model to air flow over a "Witch of Agnesi" mountain barrier are described. Comparison with the linear theory of Queney indicates, for the cases treated, that the nonlinearity of the boundary condition has a firstorder effect on the resulting flow.
 Publication:

Journal of Computational Physics
 Pub Date:
 June 1977
 DOI:
 10.1016/00219991(77)900572
 Bibcode:
 1977JCoPh..24..186C
 Keywords:

 Air Flow;
 Boundary Value Problems;
 Coordinate Transformations;
 Dynamic Models;
 Finite Difference Theory;
 Three Dimensional Flow;
 Atmospheric Models;
 Boundary Conditions;
 Earth Surface;
 Energy Budgets;
 Kinetic Theory;
 Momentum Theory;
 Mountains;
 Numerical Analysis;
 Topography;
 Fluid Mechanics and Heat Transfer