Geometric Design of a Mass Transfer Sensor for Measuring Pollutant Transport in Indoor Air
The concentration of reactive indoor air pollutants is strongly influenced by the rate at which these species are transported to the surface such as walls and carpet. To parameterize this transport, several methods have recently been developed which quantify the instantaneous and time-averaged deposition velocity, vt. If the geometry of such a device does not match the geometry of the surface, the measurement may be flawed. For devices that incorporate electronics, it may be necessary for the device to extend from a wall surface at least by the thickness of the electronic package. In this investigation, we propose the following hypothesis: the values of the transport-limited deposition velocities measured by a device enclosed in a low profile parabolic or trapezoidal enclosure are comparable to those measured on a wall in a typical room. To test the hypothesis, we apply direct numerical simulation (DNS) methods to simulate turbulent indoor fluid flow and mass transfer conditions over flat walls and a hypothetical enclosure. We find that an enclosure sufficiently deep to house electronics, with an aspect ratio of 1:10, can provide meaningful measurements that are of nearly identical to that on adjacent wall surfaces.
G. Morrison and A. B. Srirama, "Geometric Design of a Mass Transfer Sensor for Measuring Pollutant Transport in Indoor Air," Proceedings of the Air and Waste Management Association's Annual Meeting and Exhibition, Air and Waste Management Association, Jan 2004.
Civil, Architectural and Environmental Engineering
Keywords and Phrases
Computational Fluid Dynamics; Deposition Velocity Sensor; Mass Transport; Indoor air pollution
Article - Conference proceedings
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