Theoretical And Experimental Research On Particle Deposition In HVAC Ducts

Air-conditioning has been used widely. For example, it is forecasted that the proportion of new built residences which is installed with center air-conditioning will high up to 30% in shanghai till 2010.It had been proved that dusts usually accumulate in filters, ventlets and ducts in center air-conditionings, so, they apply a good growing place for bacillus, mold and virus. It easy mildew in house if it is too wet in ducts. While, it easy raise dusts in house if it is too dry in ducts, the amount of inhaleable particles in the air rise up. If filters of home air- conditionings are neglected to be cleared, it will do harm to indoor air quality.This paper introduces the relation between indoor air quality and human health firstly, and reviews the current situation of this task's investigation in home and abroad. According to known particle deposition empirical equations and experimental dates, it is discussed from particle size, duct property and some other aspects in the characteristic of particle deposition and the factors which affect deposition velocity. By comparing and analyzing dates and empirical equations, curve of particle deposition velocity in horizontal ducts and bend are fitted.There are usually monadisperse particles in the experiment, however, in the real world they are multidisperse particles. Combining fitted deposition velocity and air quality in xi'an, the amount of dust and its particle size-distribution entering from HVAC system in shan'xi history museum is presumed, In addition, takeing HVAC system of shan'xi history museum for example, its filtes' and duct's clearing time are analized.