Assessing the degree of plug flow in oxidation flow reactors (OFRs): a study on a potential aerosol mass (PAM) reactor
Assessing the degree of plug flow in oxidation flow reactors (OFRs): a study on a potential aerosol mass (PAM) reactor
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DOI：
10.5194/amt-11-1741-2018
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发表时间：
2017-11
影响因子：
3.8
通讯作者：
Dhruv Mitroo;Yujian Sun;D. Combest;Purushottam Kumar;B. Williams
中科院分区：
文献类型：
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作者：
Dhruv Mitroo;Yujian Sun;D. Combest;Purushottam Kumar;B. Williams
抽象的。氧化流反应器 (OFR) 的开发是为了在相对较短的空间时间内（定义为反应器体积与体积流量之比）实现高程度的氧化剂暴露。虽然，由于它们的使用增加，人们开始关注它们通过模拟反应器内部的化学反应来复制真实对流层反应的能力，但仍希望定制流动模式。这项工作证明了在通过实验获得这些流动模式时将反应器的示踪信号与管道的示踪信号解耦的重要性。我们通过将串联罐 (TIS) 模型（一种单参数模型）应用于反卷积算法，对华盛顿大学潜在气溶胶质量 (WU-PAM) 反应器（OFR）内的停留时间分布 (RTD) 进行了一组简单配置的建模。除具有最高时空的情况外，对于每种情况，参数 N 的值都接近于 1。综合起来，结果表明体积流量对混合模式的影响比对内部构件的使用影响更大。我们选择了最简单情况下的结果，即 78 秒时空、一个入口和一个出口、没有挡板和分布器，并将实验 F 曲线与计算流体动力学 (CFD) 模拟的曲线进行了比较。 F 曲线代表流动材料在反应器中花费的累积时间，匹配得相当好。我们重视使用小纵横比反应器（例如 WU-PAM）减少壁相互作用；然而，突然的孔径会引起流动扰动，并建议应用本工作中描述的示踪剂测试方法来研究 OFR 中的 RTD，以观察在应用之前修改入口、出口和内部构件使用的效果（例如，现场部署与实验室研究）。
Abstract. Oxidation flow reactors (OFRs) have been developed to achieve high degrees of oxidant exposures over relatively short space times (defined as the ratio of reactor volume to the volumetric flow rate). While, due to their increased use, attention has been paid to their ability to replicate realistic tropospheric reactions by modeling the chemistry inside the reactor, there is a desire to customize flow patterns. This work demonstrates the importance of decoupling tracer signal of the reactor from that of the tubing when experimentally obtaining these flow patterns. We modeled the residence time distributions (RTDs) inside the Washington University Potential Aerosol Mass (WU-PAM) reactor, an OFR, for a simple set of configurations by applying the tank-in-series (TIS) model, a one-parameter model, to a deconvolution algorithm. The value of the parameter, N, is close to unity for every case except one having the highest space time. Combined, the results suggest that volumetric flow rate affects mixing patterns more than use of our internals. We selected results from the simplest case, at 78 s space time with one inlet and one outlet, absent of baffles and spargers, and compared the experimental F curve to that of a computational fluid dynamics (CFD) simulation. The F curves, which represent the cumulative time spent in the reactor by flowing material, match reasonably well. We value that the use of a small aspect ratio reactor such as the WU-PAM reduces wall interactions; however sudden apertures introduce disturbances in the flow, and suggest applying the methodology of tracer testing described in this work to investigate RTDs in OFRs to observe the effect of modified inlets, outlets and use of internals prior to application (e.g., field deployment vs. laboratory study).