Comparison of Drift for Four Drift-Reducing Flat-fan Nozzle Types Measured in a Wind
Tunnel and Evaluated using DropletScan Software
Results of Position 1 and 2 Card Data:
Robert E. Wolf & Daniel D. Frohberg, Kansas State University, Manhattan, KS
Abstract
Objective
Four drift-reducing flat-fan nozzles were
compared for drift volume at 47 and 94 L/ha,
parallel to a 4.6 m/s wind speed, and at their
common recommended field operating psi.
This study was to compare, in a wind
tunnel, the amount of drift from venturi,
Combo-Jet, extended range, and turbo
flat-fan nozzles at the recommended
operating pressure for each.
 The extended range (XR) created
significantly more drift than the turbo flatfan (TT), Combo-Jet flat-fan (DR), and
venturi flat-fan (AI).
 The TT was significantly better for reducing
drift than the XR at 47 L/ha, but not at 94
L/ha.
 The DR and AI were not significantly
different from each other.
 For the XR, increasing the application
volume from 47 to 94 L/ha significantly
reduced the amount of drift.
 This finding did not hold true for the TT,
DR, and AI flat-fans.
 The use of drift reducing nozzle designs
significantly reduces drift.
Figure 1.
Procedures
 The mean for drift on the card in position 1 for the XR
at 47 L/ha (28.78) reflects a significantly greater drift
amount than for the TT, DR and AI tips (8.85, 1.28,
1.45).
 The TT also had significantly more drift when compared
to the DR and AI.
Figure 2
Figure 3.
 No significance was found between the DR and AI.
 At 94 L/ha, the XR created more drift than the TT, but
was not significantly different (13.2, 8.85).
A wind tunnel was used to compare drift
amounts from venturi, (AI); extended
range, (XR); turbo, (TT); and Combo-Jet,
(DR) flat-fan spray tips. The AI, XR, and
TT are Spraying Systems tips and the
DR tip is from Wilger.
 Both developed significantly more drift than the DR and
AI (2.03, 1.53).
 The DR and AI were not significantly different in the
amount of drift created.
 Tips were compared at 47 and 94 L/ha.
 Similar trends are shown at the second card location.
 Spray pressures used were 173 kPa, XR; 242
kPa, TT and DR, and 345 kPa, AI.
 For the XR flat-fan tip at both card locations, increasing
the application volume from 47 to 94 L/ha significantly
reduced the amount of drift created.
 The nozzle angle and orifice sizes used were:
110015 and 11003 for the XR and TT,
110015 and 110025 for the AI, 80015 and
8003for the DR.
 For all the other nozzle treatments, no significance was
found as the application volumes increased.
Figure 4.
 Summed across all tips and cards, there was a
significant reduction in drift as the application volume
was increased. However, the data would reflect that
the XR was responsible for the difference.
 The 015 and 025/03 orifice sizes respectively
determined the 47 and 94 L/ha application
volumes.
 Applications using water and a single nozzle
boom were made.
Means - Percent Area Coverage
Card 1 Position - 2 Meters Downwind
Means - Percent Area Coverage
Card 2 Position - 3 Meters Downwind
Controlling or minimizing the off-target
movement of sprayed crop protection
products is critical. Nozzle manufactures are
designing nozzles that will effectively reduce
the volume of driftable fines found in the spray
droplet spectra. A recent trend is to
incorporate a ‘venturi’ that includes the spray
droplet in air to lessen the drift potential.
More information about how to use the latest
nozzle technologies to maximize efficacy
while minimizing the drift potential is
important.
30
25
47 L/ha
20
94 L/ha
15
10
5
% area coverage on card
Introduction
 Each nozzle treatment was positioned parallel to
the wind and located from 45.7 to 50.8 cm above
the target.
% area coverage on card
35
 A wind speed of 4.6 m/s was maintained.
10
9
8
7
6
5
4
3
2
1
0
47 L/ha
94 L/ha
XR-173kPa
TT-242 kPa
DR-242 kPa
AI-345 kPa
0
 A 25 cm high canopy was placed on the wind
tunnel floor.
 Single water sensitive cards were placed 2, 3, and
4 meters downwind from the tip to collect the
drifting droplets.
 Four reps per treatment were analyzed.
 DropletScan software was used to analyze the
cards and determine percent area coverage – drift
amount.
 ANOVA was used to test for equality of means.
XR-173kPa
TT-242 kPa
DR-242 kPa
Nozzle Type and Pressure
AI-345 kPa
Nozzle Type and Pressure
Figure 5.
Figure 6.
Conclusions
 The recommended pressure, the four tips compared produced significantly different
amounts of drift.
 The drift reducing nozzle designs do not show drift reductions when increasing the
application volume.
 Nozzles designed to reduce drift will significantly reduce the amount of drift when
compared to XR flat-fans.
•
•
•
•
•
•
Figure 1. Drift reducing XR, TT, DR, and AI Flat-fan nozzles.
Figure 2. Wind tunnel, fan, diffuser, spires, and simulated crop canopy.
Figure 3. Boom, nozzle, and collector configuration in wind tunnel.
Figure 4. Cards in collector position 1 comparing drift (left to right) for XR, TT, DR, and AI nozzles at 47 L/ha.
Figure 5. Collector card position 1 drift means.
Figure 6. Collector card position 2 drift means.