垂直切变风场中大气污染物输送扩散的分层模式

应用分层处理法,将大气边界层中水平流场有明显转折的层次定为分界层,建立了污染物输送扩散的分层模式。研究结果表明,当上、下层流场一致时,本模式的解与传统模式基本一致。而当上、下层风向不一致时,污染物的横向散布范围被加大,地面污染轴线将随着距离增加逐渐向下层风的下风向偏移。

A DIVIDING-LAYER MODEL FOR ATMOSPHERIC POLLUTANTS TRANSPORT AND DIFFUSION IN A VERTICAL SHEAR WIND FIELD

A dividing-layer model was developed to describe the atmospheric pollutants transport and diffusion in a vertical shear wind field and the dividing layer was defined as a layer on two sides of which wind fields are different. When pollutants from a real source arrive at one side of the layer, they will transport across it only by vertical diffusion and the flux then can be looked as a new source for the other side of the layer. In the case that wind fields on both sides of the layer were same, the solution of the model was similar to that of conventional model and when wind fields were different, the model revealed that the lateral distribution range of pollutant was larger than usual and the ground concentration central line gradually leaned towards the leeward of the lower layer wind.