Conventional and ceiling mounted personalized ventilation-the dynamic effects of a moving person on personal exposure effectiveness
2014 (English)In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 935, 333-336 p.Article in journal (Refereed) Published
Ceiling mounted personalized ventilation (PV) aims to provide clean outdoor air into breathing zone of occupants directly without affecting indoor aesthetics. High momentum, at outlet of PV air terminal device (ATD), is utilized in order to avoid inducing more ambient air and let more personalized air come into breathing zone. In steady state, its performance depends much on the ceiling mounted ATD because supply air momentum, other than buoyancy effects and ambient air flow, is the major driving force in the micro-environment of occupied zone. In dynamic state, the movement of a person near PV ATD causes entrainment or detrainment effect, which can be regarded as another comparable factor influencing ceiling mounted PV performance. A typical office workplace consisting of either ceiling mounted PV ATD or conventional PV ATD and ambient air supply diffuser is simulated. One person is assumed to be seated and another moving person is simulated by dynamic meshes in computational fluid dynamics (CFD). Simulations at moving person velocities of 0.5, 1 and 1,5 m/s and distance between seated person and moving person of 0, 0.2, 0.4m are performed. A new index, computational personal exposure effectiveness, is utilized to assess the performance of the PV ATD in regard to inhaled air quality under the influence of moving person. According to numerical results, the stability of ceiling mounted PV, under dynamic environment with moving person, is better than that of conventional PV although the personal exposure effectiveness (PEE) is lower than that of conventional PV with the same personalized air flow rate in steady state.
Place, publisher, year, edition, pages
2014. Vol. 935, 333-336 p.
IdentifiersURN: urn:nbn:se:umu:diva-94851DOI: 10.4028/www.scientific.net/AMR.935.333OAI: oai:DiVA.org:umu-94851DiVA: diva2:756573