FLUENT数值模拟室内污染物扩散组分边界条件探究

Research on Component Boundary Conditions in FLUENT Numerical Simulation of Indoor Pollutant Diffusion

基于FLUENT15.0应用质量入口(mass flow inlet)作为组分边界条件,对室内甲醛扩散的浓度分布进行数值模拟,探究质量入口边界参数质量流量、组分质量分数、湍流指定方式对浓度数值结果的影响。结果表明:质量流量的不同会导致数值结果的差异,其参数值的设定对数值结果的准确性有直接影响;组分质量分数数量级增大,计算所得甲醛浓度则增大为同等数量级,对室内甲醛浓度的分布起决定性作用;质量入口湍流指定方式也会导致数值结果不同。因此,组分边界条件参数的正确、合理设置,是室内污染物扩散数值模拟极为关键的一个环节。

This paper carried out the numerical simulation of indoor formaldehyde diffusion concentration distribution based on FLUENT15.0 and mass flow inlet as component boundary condition,investigated the influences of mass inlet boundary parameters such as mass flow rate,mass fraction of components and turbulence assignment mode on the numerical results of concentration.The results show that the difference of mass flow rate will lead to the difference of numerical results,and the setting of parameters has a direct effect on the accuracy of numerical results;when the order of magnitude of component mass fraction increases,the calculated formaldehyde concentration increases to the same order of magnitude,which plays a decisive role in the indoor formaldehyde concentration distribution;the specified mode of mass inlet turbulence will also lead to different numerical results.Therefore,the correct and reasonable setting of parameters of component boundary conditions is a very important link in the numerical simulation of indoor pollutant diffusion.