Simulation of Flow in Continuous-Flow Cloud Condensation Nuclei Counter (DMT-CCNC)

doi:10.13209/j.0479-8023.2017.015

Abstract

Abstract:

The velocity, temperature and humidity in the chamber of the Continuous Flow Streamwise Thermal-Gradient CCN Counter manufactured by DMT were successfully simulated using the computational fluid dynamics software ANSYS FLUENT. With velocity of 0.0164, 0.0185, 0.0205, 0.0226, 0.0246 m/s and temperature settings of ΔT 2, 8 and 17 K, the influence of velocity and temperature on the flow were tested. Results show that, velocity and temperature setting of CCNC influenced both velocity field and temperature field. When ∆T=8 K, v=0.0205 m/s, the supersaturaiton on the centerline was about 0.27%. Supersaturation in the CCNC chamber was simulated successfully.

Key words: CCNC, ANSYS FLUENT, velocity field, temperature field, water vapor field

摘要：

运用计算流体力学模型 ANSYS FLUENT, 对 DMT 公司的恒流热梯度云凝结核计数器(CCNC)云室内的流场、温度场以及水汽场进行模拟。依据外场观测和室内实验中的常用进气流速 0.0164, 0.0185, 0.0205, 0.0226 和 0.0246 m/s 以及云室温差 2, 8 和 17 K, 对比不同进气流速和云室温差对云室内流场的影响。结果显示, 云室内的速度场和温度场均受进气流速和云室温差的影响。当云室温差为 8 K, 进气流速为 0.0205 m/s时, 模拟出的云室中心线的过饱和度约为0.27%, 较好地模拟出云室内的水汽过饱和状态。

关键词: 云凝结核计数器(CCNC), ANSYS FLUENT, 速度场, 温度场, 水汽场

Renjie YU, Chunsheng ZHAO, Huiwen XUE, Nan MA, Jiangchuan TAO, Shizuo FU, Jianpeng ZHANG, Ye KUANG, Hongjian LIU, Yuxuan BIAN. Simulation of Flow in Continuous-Flow Cloud Condensation Nuclei Counter (DMT-CCNC)[J]. Acta Scientiarum Naturalium Universitatis Pekinensis, 2017, 53(5): 817-824.

于仁杰, 赵春生, 薛惠文, 马楠, 陶江川, 付仕佐, 张健鹏, 旷烨, 刘宏剑, 边宇轩. FLUENT对云凝结核计数器云室内气流特征的模拟研究[J]. 北京大学学报自然科学版, 2017, 53(5): 817-824.

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URL: https://xbna.pku.edu.cn/EN/10.13209/j.0479-8023.2017.015

https://xbna.pku.edu.cn/EN/Y2017/V53/I5/817

Figures/Tables 9

Fig. 1 CCNC chamber

Fig. 2 Theory of supersaturation generation of CCNC chamber

Fig. 3 Velocity field in CCNC chamber when ∆T is set respectively at 2, 8, 17 K, and inlet flow velocity is 0.0205 m/s

Fig. 4 Velocity results in the middle of CCNC chamber when ∆T is set respectively at 2, 8, 17 K, and inlet flow velocity varies from 0.0164 m/s to 0.0246 m/s

Fig. 5 Temperature field in CCNC chamber when ∆T is set respectively at 2, 8, 17 K, and inlet flow velocity is 0.0205 m/s

Fig. 6 Temperature in the middle of CCNC chamber when ∆T is set respectively at 2, 8, 17 K, and inlet flow velocity varies from 0.0164 m/s to 0.0246 m/s

Fig. 7 Vapor pressure field in CCNC chamber when ∆T is set at 8 K, and inlet flow velocity is 0.0205 m/s

Fig. 8 Saturation vapor pressure field in CCNC chamber when ∆T is set at 8 K, and inlet flow velocity is 0.0205 m/s

Fig. 9 Relative humidity field in CCNC chamber when ∆T is set at 8 K, and inlet flow velocity is 0.0205 m/s

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