热浮升烟流扩散的拉格朗日粒子模拟

Lagrangian Particle Simulation of Buoyant-Plume Dispersion

本文建立了一个处理对流边界层热浮升烟流扩散的拉格朗日粒子模式。模式既考虑了对流边界层的特殊气流结构，并作了均匀湍流参数化的简化；同时提出了在拉格朗日模式中合理计入热浮升烟流抬升影响的近似方法。模拟计算结果表明：烟流热浮力的影响使得地面最大浓度值远比被动烟流的低，而且出现位置离源更远。模式计算与外场试验结果合理地一致。模式物理概念明确合理，输入参数少，计算量小，具有简单实用的优点，适合日常环境应用需要。

In this paper, the Lagrangian particle model based on authors' study to simulate the dispersion of the passive plume in the CBL was developed in a simple and approximate manner to deal with the dispersion of practical buoyant-plumes. The special flow structure in the CBL was introduced into the model and homogeneous turbulence assumption was made. A simple and approximate method was further proposed to account for the effects of buoyancy. The simulation shows that the buoyancy results in lower ground-level maximum concentration which appears in farther distance downwind the source than those of passive-plume. Model results were found to be in good agreement with laboratory and field measurements. The model is better than other models, because it uses less input parameters and computer resources, reasonable simplicities and is feasible.