Aerosol scrubbing removal under high Weber number immersed jet condition
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摘要: 基于射流穿透长度与夹带液滴分数等水力模型,建立了混合气体射流条件下气溶胶惯性碰撞去除模型,通过对注入区空间离散构建了高韦伯数射流流型含气芯夹带特征的气溶胶水洗去除分析方法。采用气溶胶水洗机理实验装置开展的两组蒸汽份额为64%,淹没深度为0.7 m,质量通量分别为217 kg/(m2·s)和120 kg/(m2·s)实验,以及引用淹没深度为0.5 m、质量通量为95 kg/(m2·s)的纯不凝性气体载带气溶胶的RCA2实验结果,对分析方法进行了验证。结果表明:考虑射流水力学特征的气溶胶水洗去除模型的预测结果与实验值符合较好,通过参数分析发现随着射流韦伯数的增加,射流穿透长度和夹带液滴分数均增加,增强了气溶胶与液滴的惯性碰撞作用。Abstract: This paper presents a model for aerosol inertial collision removal under mixed gas jet conditions with high Weber number, based on the hydrodynamic model of jet penetration length and entrained droplet fraction. An analysis code of the aerosol pool scrubbing is constructed by spatial discretization of the injection zone. The experimental cases are adopted to validate the model, including two cases of 64% steam fraction, 0.7 m submergence depth, and mass fluxes of 217 kg/(m2·s) and 120 kg/(m2·s), conducted by small scale aerosol pool scrubbing facility, and one Reinforced Concerted Action 2 (RCA2) experiment with non-condensable gas-carrying aerosols at 0.5 m submergence depth and mass fluxes of 95 kg/(m2·s). The results show that the predictions of the model considering the jet hydrodynamic characteristics are in good agreement with the experimental values. Parameter analysis shows that as the Weber number of immersed jet increases, both jet penetration length and entrained droplet fraction increase, thereby enhancing the inertial collision between aerosols and droplets.
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Key words:
- aerosol /
- pool scrubbing /
- jet /
- inertial collision /
- decontamination factor
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表 1 实验条件及结果
Table 1. Test conditions and results
experiment mass flux/
(kg·m−2·s−1)Weber
numbersteam
fraction/%submerged
depth/mmaterial mass median
diameter/μmdecontamination
factorSCAPS-1 217 3.5×106 64 0.7 TiO2 0.5 215±62.4 SCAPS-2 120 1.8×106 64 0.7 TiO2 0.5 58±16.8 RCA2[6] 95 2.9×105 0 0.5 Ni 1.3 28±12.3 -
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