中文摘要：

基于动态光散射法,采用同差探测实现了纳米流体分散体系的粒度测量。对体积分数为0.005%和0.0025%浓度的SiO2/H2O纳米流体颗粒粒径进行了测量,粒径的实验值的平均偏差分别为1.37%和1.39%,可以满足纳米颗粒粒径的高精度测量要求。两种浓度的SiO2/H2O纳米流体的平均粒径基本一致,偏差在实验的不确定度以内,且随时间无明显变化,证明了颗粒分散的稳定性,本方法可以用于纳米流体分散稳定性的评价。

英文摘要：

A new system for nanofluid’s particle size measurement was built based on the dynamic light scattering method.The homodyne scheme was used to analyze light intensity signal.SiO2’s particle sizes were measured within the SiO2/H2O nanofluids with volume fractions of 0.005%and0.0025%,separately.The average deviations of the results were 1.37%and 1.39%,separately.The results can meet the high accuracy requirement of the particle size measurement of nanoparticles.The average particle sizes in two nanofluids with different volume fraction were same,and the deviations were within the uncertainty of the experiment.The sizes were constant with time passed by,which can prove the stability of the nanofluid.This method could be used for evaluating the stability of nanofluid.