Particle–Focusing Characteristics of Matched Aerodynamic Lenses

Figures & data

Figure 1 Variation of various focusing parameters with the orifice length (with Stk _orifice , σ_g and enhancement are represented on the left y axis and mass flow rate on the right y axis).

Figure 2 A schematic of the straight rectangular slots with the choked orifice.

Figure 3 Variation of the slot width with the operating pressure of the lens.

Table 1 Dimensions (in mm) of the normal and V–slots investigated by this work

Dimensions	Normal slots	V–slots
Length (L)	10	80
Width (W)	0.58	0.28
Angle (α)	N/A	15°
Axial length (l)	N/A	300

Figure 4 Variation of Stk _slot and σ_g of focused particles perpendicular to the length of an X–slot (P = 0.001 atm).

Figure 5 Variation of Stk _slot and σ_g of focused particles perpendicular to the length of the slot (P = 0.01 atm).

Figure 6 Variation of the V–slot dimensions with tube diameter at a pressure of 0.25 atm.

Figure 7 Symmetric 2D section of the capped V–slot geometry.

Table 2 Preliminary focusing characteristics of the V–shaped slots at different pressures

			Mass flow rate
Pressure (in atm)	Stk slot	σg	(mg/s)
0.0025	1.03	2.84	38.2
0.025	0.96	3.83	330

Figure 8 Variation of Stk _slot with normalized radial distance in capped V–shaped slots at different operating pressures.

Figure 9 Variation of σ_g with normalized radial distance in capped V–shaped slots at different operating pressures.

Variation of focusing characteristics of V–shaped capped slots with the cap–slot spacing at 0.0025 and 0.05 atmospheres

Pressure	Spacing			Mass flow rate
(atmospheres)	(mm)	Stk slot	σg	(mg/s)
0.0025	0.3	1.67	3.27	35.6
	0.5	1.95	3.04	37.0
	1.0	1.61	2.10	37.5
0.05	0.3	0.31	2.66	710
	0.5	0.61	3.70	718
	1.0	0.58	3.47	770