Abstract: In order to study fouling of magnesium oxide nano-particles in alternating elliptical axis tube，magnesium oxide nano-particles were used to prepare colloidal solution as the study object. According to particulate size，particle concentration，liquid velocity and temperature，several groups of experiments were perfomed in the alternating elliptical axis tube. Scanning electron microscope was used to observe the fouling surface of the heat exchanger. The results show that particulate fouling of the alternating elliptical axis tube had no apparent induction period. Under the same conditions，the smaller the particulate size，the greater the fouling rate and asymptotic value of fouling resistance. The fouling rate and asymptotic value of fouling resistance increased with increasing particle concentration and decreased with increasing flow rate. The higher the inlet temperature，the smaller the asymptotic value of fouling resistance.

Key words: alternating elliptical axis tube, nanoparticles, fouling, colloid, fouling characteristics

摘要： 为探讨纳米氧化镁颗粒在交叉缩放椭圆管内部的污垢规律，本文选用纳米氧化镁颗粒配置纯胶体溶液为研究对象，对不同颗粒直径、颗粒浓度、工质流速和温度工况下交叉缩放椭圆管的污垢特性进行了实验研究，并通过扫描电镜观察其结垢表面。结果表明：交叉缩放椭圆管纳米颗粒污垢下无明显诱导期；在相同的工况下，颗粒粒径越小，结垢速率越快，污垢热阻渐近值越大；随着颗粒浓度的增加，结垢速率加快，污垢热阻渐近值明显增大；随着流速的增加，污垢热阻渐近值和结垢速率都有所降低；污垢热阻渐近值随着实验管段入口温度的升高而降低。

关键词: 交叉缩放椭圆管, 纳米粒子, 结垢, 胶体, 污垢特性