| 6 | 0 | 10 |
| 下载次数 | 被引频次 | 阅读次数 |
目的:进一步降低冷凝粒子计数器检测颗粒的粒径下限。方法:基于颗粒冷凝生长技术，在已有的三段式颗粒生长装置设计上，新增一个“采样段”;通过调整该采样段的温度和流速，达到降低检测颗粒粒径下限的目的。结果:实验结果表明：在四段式颗粒生长装置中，当采样段的温度从30℃降低至5℃时，颗粒的中值粒径从3.28μm增加至3.79μm;当采样段流速从0.2 L/min降低至0.1 L/min时，颗粒中值粒径从3.05μm增加至4.07μm。数值模拟结果表明：在四段式颗粒生长装置中，当采样段温度从30℃降低至5℃时，系统过饱和峰值增加约0.3;检测颗粒的粒径下限从1.72 nm降低至1.56 nm。当采样段流速从0.21 L/min降低至0.03 L/min时，系统过饱和峰值增加约0.2;检测颗粒的粒径下限从1.69 nm降低至1.59 nm。结论:新的四段式设计，通过降低采样段的温度及流速，进一步提升了系统的过饱和峰值、增加了颗粒中值粒径，降低了检测颗粒的粒径下限。
Abstract：Aims: This paper aims to further reduce the lower detection limit of particle size in condensation particle counters. Methods: Based on the particle condensation growth technology, a “sampler” was integrated into the existing three-stage particle growth device design. By precisely adjusting the temperature and flow velocity within this stage, the lower detection limit of particle size could be effectively reduced. Results: The experimental results showed that in a four-stage particle growth system, when the temperature of the sampler was decreased from 30 ℃ to 5 ℃, the median particle size increased from 3.28 μm to 3.79 μm. When the flow rate in the sampler was reduced from 0.2 L/min to 0.1 L/min, the median particle size increased from 3.05 μm to 4.07 μm. Numerical simulations of the four-stage particle growth device revealed that the reducing of the sampler temperature from 30 ℃ to 5 ℃ increased the system's supersaturation peak value by approximately 0.3, thereby lowering the particle size detection limit from 1.72 nm to 1.56 nm. Similarly, the decreasing of the sampler flow rate from 0.21 L/min to 0.03 L/min enhanced the supersaturation peak by 0.2 and reduced the detection limit from 1.69 nm to 1.59 nm. Conclusions: Reducing the temperature and flow rate in the sampler further enhances the system's supersaturation peak, increases the median particle size, and lowers the detection lower limit for particle size.
[1] PAVLIDIS D,SIPPIAL D J,FLOROU K,et al.Exploring the discrepancies between SMPS and AMS measurements in secondary organic aerosol formation experiments[J].Aerosol Science and Technology,2024,58(2):195-205.
[2] BALENDRA S,KALE A,PONGETTI J,et al.Condensation particle counters:Exploring the limits of miniaturisation[J].Journal of Aerosol Science,2024,175:106266.
[3] ZERVAKI O,DIONYSIOU D D,KULKARNI P.Compact,high-flow,water-based,turbulent-mixing,condensation aerosol concentrator for collection of spot samples[J].Aerosol Science and Technology,2024,58(8):889-901.
[4] AGARWAL J K,SEM G J.Continuous flow,single-particle-counting condensation nucleus counter[J].Journal of Aerosol Science,1980,11(4):343-357.
[5] SEM G J.Design and performance characteristics of three continuous-flow condensation particle counters:A summary[J].Atmospheric Research,2002,62(3-4):267-294.
[6] HAO W X,MEI F,HERING S,et al.Mapping the performance of a versatile water-based condensation particle counter (vWCPC) with COMSOL simulation and experimental study[J].Atmospheric Measurement Techniques Discussions,2023,16(17):3973-3986.
[7] MAGNUSSON L E,KOROPCHAK J A,ANISIMOV M P,et al.Correlations for vapor nucleating critical embryo parameters[J].Journal of Physical and Chemical Reference Data,2003,32(4):1387-1410.
[8] KUPC A,BISCHOF O,TRITSCHER T,et al.Laboratory characterization of a new nano-water-based CPC 3788 and performance comparison to an ultrafine butanol-based CPC 3776[J].Aerosol Science and Technology,2013,47(2):183-191.
[9] LI Y R,CHEN X T,WU J,et al.A convertible condensation particle counter using alcohol or water as the working fluid[J].Aerosol Science and Technology,2025,59(2):185-194.
[10] HERING S V,SPIELMAN S R,LEWIS G S.Moderated,water-based,condensational particle growth in a laminar flow[J].Aerosol Science and Technology,2014,48(4):401-408.
[11] BIAN J J,GUI H Q,WEI X L,et al.Development and application of a wide dynamic range and high resolution atmospheric aerosol water-based supersaturation condensation growth measurement system[J].Atmosphere,2021,12(5):558.
[12] HERING S V,LEWIS G S,SPIELMAN S R,et al.A MAGIC concept for self-sustained,water-based,ultrafine particle counting[J].Aerosol Science and Technology,2019,53(1):63-72.
[13] HERING S V,LEWIS G S,SPIELMAN S R,et al.Detection near 1-nm with a laminar-flow,water-based condensation particle counter[J].Aerosol Science and Technology,2017,51(3):354-362.
[14] FLUENT A.Ansys Fluent Theory Guide[M].USA:Ansys Inc,2011:724-746.
[15] AMOR C F.A graphical solution of the Kelvin equation[J].Journal of the Institution of Electrical Engineers,1961,7(73):22-24.
[16] KELTON K F,GREER A L.Heterogeneous nucleation[J].Tettamanzy,2010,18(9):287-360.
[17] HERING S V,STOLZENBURG M R.A method for particle size amplification by water condensation in a laminar,thermally diffusive flow[J].Aerosol Science and Technology,2005,39(5):428-436.
[18] TAYLOR P,LIU W,KAUFMAN S L,et al.Water-based condensation particle counters for environmental monitoring of ultrafine particles water-based condensation particle counters for environmental monitoring of ultrafine particles[J].Journal of the Air & Waste Management,2014,56(4):37-41.
[19] BIAN J J,GUI H Q,XIE Z B,et al.Simulation of three-stage operating temperature for supersaturation water-based condensational growth tube[J].Journal of Environmental Sciences,2020,90:275-285.
[20] HERING S V,STOLZENBURG M R,QUANT F R,et al.A laminar-flow,water-based condensation particle counter (WCPC)[J].Aerosol Science and Technology,2005,39(7):659-672.
基本信息:
DOI：
中图分类号:TB383.1
引用信息:
[1]陈曦,李旭娟,于明州.四段式水基纳米颗粒冷凝生长装置的研究[J].中国计量大学学报,2025,36(01):17-25.
基金信息:
国家自然科学基金项目(No.11872353); 浙江省自然科学基金项目(No.LZ22A020004)