目前对颗粒污垢的研究主要局限于实验研究，通过实验和模拟的手段分别对微米和纳米颗粒污垢沉积的内在关系研究较少。为了研究静止流体中纳米级颗粒污垢与微米颗粒污垢出现相似沉积特点的原因，分别在不同工况下进行纳米颗粒污垢和微米颗粒污垢的沉积实验，并应用扫描电镜对试片表面进行观测。通过模拟方式得出不同粒径微米颗粒污垢的沉积质量，由实验得出颗粒污垢沉积质量呈现出渐进增长趋势。随着浓度的增大其渐进沉积质量越来越大，达到渐进污垢沉积量的时间越来越短。由于颗粒间的团聚效应，使纳米颗粒污垢出现与微米颗粒污垢相似的沉积规律。基于这种规律，提出纳米颗粒污垢等效直径的概念。将实验结果与不同直径微米级颗粒沉积模拟结果相结合，得出浓度0.4g/L 的纳米悬浮液团聚后的等效直径约为9.2μm；浓度0.6g/L的纳米颗粒悬浮液团聚后的等效直径约为11.2μm。%Particulate fouling research is mainly done by experiment at present. There are hardly any research on internal relationship between nanometer and micrometer particles fouling through simulation and experiment. There are some similar deposition characteristics between nanoparticle and micro particle fouling. Nanoparticle and micro particle fouling deposition experiments were conducted under different working conditions,and surface characteristics were observed by SEM. The fouling deposition quantity was determined by simulation with different particle sizes. A gradual growth trend of deposition quantity of particles fouling was observed. Due to agglomeration effect,there was similar deposition result between nanoparticles and micro particles fouling. The equivalent diameter was proposed for nanoparticles by combining the nanoparticles experiment and micro particles simulation results. The equivalent diameter was 9.2μm for 0.4g/L nanometer suspensions. The equivalent diameter was 11.2μm for 0.6g/L nanometer suspensions.
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