Modeling and Simulation of Momentum and Heat Transfer in the Atmospheric Boundary Layer over Rough Surface: Study with Improved Turbulence Model

摘要

In the present study we are focused on the mesoscale simulation of turbulent momentum and heat transfer in the stably stratified boundary layer over a flat urbanized surface by using the improved three-parameter turbulence model in which buoyancy effects are accurately taken into account [1]. A horizontal inhomogeneity of a mechanical nature is accompanied by a thermal inhomogeneity. In some field studies, urbanized surfaces were observed to be generally warmer than the adjacent vicinities. This situation is referred to as an urban heat island [2]. Aerodynamic roughness and the urban heat island produce significant disturbances in the wind and temperature fields due to an intense upward flow of warm unstable air. This flow is induced by the horizontal temperature gradient between the more strongly heated air over the urbanized surface and the less heated air over its environs [1]. In this case, vertical turbulent heat transfer has a nonlocal (countergradient) character [3].