Abstract The Differential Mobility Analyzer (DMA) is currently the most effective instrument for sizing sub-micrometer aerosol particles. An important requirement to ensure good performance in terms of sizing accuracy and resolution is that the flow field remains laminar and undisturbed along its classification zone. To achieve that, a flow straightener (or flow laminarizer) is employed at the sheath flow inlet, located at the top of the classification column. In this study, we assess the performance of a custom-made DMA using different sheath flow straighteners made out of plastic fabric materials or built by 3D printing. Our tests show that 3D-printed flow straighteners can achieve comparable, and in some cases better, results to those used in commercial DMAs (e.g., fine nylon meshes; Dacron®). Considering the great flexibility and ease in manufacturing offered by 3D printing, our findings show that this technology provides a promising alternative for building enhanced flow straightening systems.

中文翻译：

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使用 3D 打印的流动矫直器提高差分迁移率分析仪的性能

摘要 微分迁移率分析仪 (DMA) 是目前用于测量亚微米气溶胶颗粒大小的最有效仪器。在尺寸精度和分辨率方面确保良好性能的一个重要要求是流场沿其分类区域保持层流且不受干扰。为此，在位于分级柱顶部的鞘流入口处采用了流动矫直器（或流动层流器）。在这项研究中，我们评估了使用由塑料织物材料制成或通过 3D 打印制造的不同鞘流矫直器的定制 DMA 的性能。我们的测试表明，3D 打印的流动矫直器可以实现与商业 DMA（例如细尼龙网；Dacron®）中使用的结果相当的结果，在某些情况下甚至更好。