气溶胶粒子在毛细管中沉积与再悬浮

Deposition and resuspension of aerosol particles in capillary tube.

采用亚微米单分散聚苯乙烯球形硬气溶胶粒子和脉冲进样技术,测定了气溶胶粒子在管道中的沉积率,研究了沉积率与流体速度、管道长度、管道直径和气溶胶粒子大小之间的关系.结果发现,在相同条件下,沉积率随管长增加而增大;随流体速度增加而减小.在相同体积流量下,沉积率与管径关系不大;而沉积率与气溶胶粒子大小之间的关系比较复杂.沉积的气溶胶粒子如果在更大流速冲击下,将发生反弹,部分气溶胶粒子从黏附表面上分离再次悬浮于流体中.

The deposition rate of aerosol particles in capillary tube was measured with submicrometer monodisperse polystyrene spheres solid aerosol particles and pulse sample inserting technique; and studies were made on the relationship between the flow velocity, the tube diameter, the tube length and aerosol particles size. Under same conditions the deposition rate increased with the tube length and decreased with the flow velocity. The tube diameter had light relation with deposition rate under same volume flow amount, while the relation of deposition rate with aerosol particles size was relatively complicated. The aerosol particles adhered on the surface might partially separate and resuspense under lashing of higher flow velocity.