壁挂炉排放颗粒在建筑之间的扩散特性

Diffusion of Particles from Wall-mounted Boiler in Residential Zone

本文利用湍流-模型及离散相模型(DPM)数值研究了当两栋建筑之间设置燃气壁挂炉时,排烟中粒径为1μm、10μm和100μm的颗粒物的扩散特性及其对建筑物周围环境的影响。结果表明:来流方向和颗粒尺寸均会影响排烟颗粒物的扩散。燃气壁挂炉排烟方向与来流风向相反时,在两栋建筑物中间形成的大尺度涡旋,有利于大尺度颗粒物的扩散;当排烟方向与来流方向相同时,建筑物中间所形成的涡旋,使颗粒物的扩散困难,颗粒物在排放口附近积聚明显,恶化了排放建筑附近的空气质量。1μm和10μm粒径的颗粒物追随流体的性能好,其运行轨迹主要受流体影响。100μm粒径颗粒物因其自身重力较大,颗粒物运行轨迹主要受重力影响,其对环境的影响取决于重力与涡的力量平衡。

With the turbulence model of- and the Dispersed Phased Model(DPM) the diffusion characteristics of smoke from the exits of wall-mounted gas boilers between two buildings in residential zones are studied.The sizes of the smoke particles are 1μm,10μm and 100μm.The results show that both the direction of wind and the size of particles affect the diffusion of smoke.When the direction of wind is opposite the smoke the vortex formed between the two buildings enhances the diffusion of large scale particles,while when the direction of wind is opposite that of smoke it impedes the diffusion resulting in the accumulation of smoke particles around the vent and the worse air quality there.The particles,the size of which is in between 1μm and10μm follow well the wind.The track of them is mainly affected by the motion of wind.The motion track of 100μm particles is affected greatly by the gravity of them and the diffusion of them depends on the balance of the gravity and the energy of vortex.