treasure valley road dust study: final report - ResearchGate

Fractional Line Loss
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1
-1.2
Background
Right
Left
Precision
0.56
0.72
0.92
1.16
1.44
2.04
2.88
3.95
5.59
7.21
9.87
13.96
19.75
28.22
40.31
Aerodynamic Particle Size (um)
Figure 3-11. Fractional line losses associated with each of the particle sizes measured by the GRIMM PSA
and collocated instrument precision for TRAKER right, background, and left inlets.
Fractional Line Loss
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.2
0.56
0.72
0.92
1.16
1.44
2.04
2.88
3.95
5.59
7.21
9.87
13.96
19.75
28.22
40.31
DT_PM2.5
DT_PM10
Aerodynamic Particle Size (um)
Figure 3-12. Average fractional line loss for left, background, and right TRAKER inlet lines.
3.3.3 Particle Concentration Dilution
Flowrates through the dilution lines were set to approximately achieve ten fold dilution.
However, since the rotameters used are temperature and pressure sensitive, actual dilution was
determined by performing a line losstest as described in section 3.3.2. Figure 3-13 shows the
fractional line losses associated with each particle size bin for the TRAKER inlets when the
dilution system is in operation.
As was the case without dilution, there are no consistent differences between the diluted
left and right inlets within the limits of measurement uncertainty. Thus, the average shown in
Figure 3-14 is used to correct particle concentrations for both inlets.
3-13