Counting efficiency is an important performance indicator of condensation particle counter ( CPC) , witch is influenced by several factors such as the working mode, working fluid, physical and chemical properties of the particle to be tested, temperature of condenser and saturator and the flow field of condenser. In order to find the in-fluence of multiple factors on counting efficiency and explicit prediction model, the paper engaged sodium chloride particle as particle source to investigate the butanol based condensation particle counter developed by the team. The experiment conditions were determined engaging the method of response surface in the Design Expert. The results show that the influence of condenser temperature variation on efficiency is more significant than that of saturator temperature, and the flow velocity of condenser and sample tube have less influence on counting efficiency, while they have obvious interactive influence on the cut-off particle size, besides, there is an optimal velocity difference between condenser and sample tube velocity, under which the counter can reach the highest counting efficiency. The empirical formula for predicting the cut-off size of condensation particle counter can be derived and used to pre-dict the cut-off size and describe the relationship between these factors and the counting efficiency.%计数效率是表明凝聚核粒子计数器(CPC)计数性能的重要指标,受计数器工作方式、工质种类、测试粒子物理化学特性、饱和器冷凝器温度以及冷凝器内流场等多重因素的影响.为明确多重因素对计数效率的影响关系,并确定切割粒径的预测模型,以氯化钠细颗粒物为粒子源,采用响应曲面实验设计方法设计实验工况点研究自主研发的正丁醇基凝聚核粒子计数器特性关系.研究结果表明:冷凝器温度变化对切割粒径的影响明显高于饱和器温度变化对切割粒径的影响,采样器流速和冷凝器内流速对切割粒径的作用不明显;采样器流速与冷凝器流速对切割粒径的交互影响显著,且采样器流速、冷凝器流速之间存在流速差使计数效率最优;研究得到凝聚核粒子计数器切割粒径预测公式,且公式能较好地利用各参数描述切割粒径.
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