Ultrafine Particles Deposition Inside Passenger Vehicles

Figures & data

TABLE 1 Information of test vehicles in this study

Vehicle	Year and model	Volume (m^3)	In-cabin surface area (m^2)	Interior surface material
A	1997 Isuzu Rodeo (SUV)	4.59	18.17	carpet, cotton
B	1996 Saturn SL2 car (compact)	2.45	17.76	carpet, cotton
C	2005 Ford F-250 Super Duty (truck)	1.72	13.98	leather, rubber

FIG. 1 The average air velocity inside test vehicles under various vehicle speeds and ventilation settings.

FIG. 2 Schematic diagram of the experimental setup.

FIG. 3 The relationship between ln(C/C₀) and time for (a) 30 nm, (b) 66.1 nm, and (c) 101.8 nm particles inside the Isuzu Rodeo SUV.

FIG. 4 The particle deposition rates as a function of particle size under various in-cabin air flow conditions inside three test vehicles (a) Isuzu Rodeo SUV, (b) Saturn SL2 car, and (c) Ford F-250 Super Duty truck.

FIG. 5 Relative ratio of particle deposition rates for 30, 66.1, and 101.8 nm particles under two air flow conditions (V₃ = 0.65 m s^–1 and V₀ = natural convection) inside three test vehicles.

FIG. 6 The effects of the number of passengers inside (a) Isuzu Rodeo SUV, (b) Saturn SL2 car, and (c) Ford F-250 Super Duty truck on particle deposition rates.

FIG. 7 The particle deposition rates as a function of surface area to volume ratios for 30, 66.1, and 101.8 nm particles inside two test vehicles.

FIG. 8 Mean particle deposition rates as a function of particle size inside three test vehicles under four in-cabin air conditions.

FIG. 9 A comparison of particle deposition rates inside vehicles and indoors.

TABLE 2 A summary of experimental conditions of indoor particle deposition studies compared in Figure 9

Study	Test location	Particle source or type	Volume (m^3)
Abt et al. (2000)	Residential house	Indoor human activities and outdoor particles	—
Long et al. (2001)	Residential house (nonsmoking)	Ambient	—
Mosley et al. (2001)	Experimental chamber	Oil particles generator, KCL and incense particles	19
Vette et al. (2001)	Residential house (unoccupied)	Ambient	—
Wallace et al. (2004a)	Townhouse	Cooking	400
Wallace et al. (2004b)	Townhouse	Cooking, candle	400
Zhu et al. (2005)	Residential apartment	Outdoor particles from freeways	26
This study	In-cabin microenvironment	Diesel engine exhaust	3

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