This study investigates the performance of two systems: personalized ventilation (PV) and ductless personalized ventilation (DPV). Even though the literature indicates a compelling performance of PV, it is not often used in practice due to its impracticality. Therefore, the present study assesses the possibility of replacing the inflexible PV with DPV in office rooms equipped with displacement ventilation (DV) in the summer season. Numerical simulations were utilized to evaluate the inhaled concentration of pollutants when PV and DPV are used. The systems were compared in a simulated office with two occupants: a susceptible occupant and a source occupant. Three types of pollution were simulated: exhaled infectious air, dermally emitted contamination, and room contamination from a passive source. Results indicated that PV improved the inhaled air quality regardless of the location of the pollution source; a higher PV supply flow rate positively impacted the inhaled air quality. Contrarily, the performance of DPV was highly sensitive to the source location and the personalized flow rate. A higher DPV flow rate tends to decrease the inhaled air quality due to increased mixing of pollutants in the room. Moreover, both systems achieved better results when the personalized system of the source occupant was switched off.

中文翻译：

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无管道个性化通风能否替代常规管道个性化通风？

本研究调查了两个系统的性能：个性化通风 (PV) 和无管个性化通风 (DPV)。尽管文献表明 PV 具有引人注目的性能，但由于其不切实际，它在实践中并不经常使用。因此，本研究评估了在夏季在配备置换通风 (DV) 的办公室中用 DPV 替换刚性 PV 的可能性。当使用 PV 和 DPV 时，数值模拟被用来评估污染物的吸入浓度。在模拟办公室中对系统进行了比较，其中有两个居住者：易感居住者和源居住者。模拟了三种类型的污染：呼出的传染性空气、皮肤排放的污染和来自被动源的房间污染。结果表明，无论污染源位于何处，PV都能改善吸入空气质量；较高的 PV 供应流量对吸入的空气质量产生积极影响。相反，DPV 的性能对源位置和个性化流量高度敏感。由于室内污染物混合增加，较高的 DPV 流速往往会降低吸入的空气质量。此外，当源占​​用者的个性化系统关闭时，这两个系统都取得了更好的结果。由于室内污染物混合增加，较高的 DPV 流速往往会降低吸入的空气质量。此外，当源占​​用者的个性化系统关闭时，这两个系统都取得了更好的结果。由于室内污染物混合增加，较高的 DPV 流速往往会降低吸入的空气质量。此外，当源占​​用者的个性化系统关闭时，这两个系统都取得了更好的结果。