Evaluation of the spray characteristics of a single droplet with imaging techniques
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Evaluation of the spray characteristics of a single droplet with imaging techniques S. VULGARAKIS MINOV 1&2 , F. COINTAULT 1 , D. NUYTTENS 2 , J. VANGEYTE 2 , J. PIETERS 3 , B.HIJAZI 1&2 AGROSUP DIJON INSTITUT NATIONAL SUPÉRIEUR DES SCIENCES AGRONOMIQUES DE L’ALIMENTATION ET DE L’ENVIRONNEMENT Département Agronomie Agroéquipements Elevage & Environnement (D2A2E) 26 Bd Dr Petitjean - BP 87999 - 21079 Dijon cedex - France +33 (0)380772348 - +33 (0)380772551 – Site Web : http://www.agrosupdijon.fr 1) AgroSup Dijon – UP GAP – 26, Bd Dr Petitjean – BP 87999 – 21079 Dijon cedex – France 2) Institute for Agricultural and Fisheries Research (ILVO) - Technology and Food Science Unit, Agricultural Engineering Research Group – Burg. Van Gansberghelaan 115 – 9820 Merelbeke – Belgium 3) Department of Biosystems Engineering – Faculty of Bioscience Engineering- Ghent University – Coupure Links 653-9000 Gent - Belgium Improvement of existing techniques Development of accurate spray quantification techniques. Motivatio n Pesticide s Sprayers Nozzles Application accuracy and efficiency of plant protection products Maximization of spray efficiency and minimizing residues and off target losses Material and methods Image acquisition system Droplet generator setup: 1- Droplet generator with piezoelectric element, 2-HS camera & lens, 3-Light source, 4-PC, 5-Pressure supplier, 6- Signal amplifier, 7- Pulse generator, 8- Liquid tank. Droplet generator Droplet generator: 1- Glass nozzle,2- Piezoelectric element, 3- Clamp, 4-Tubes. Glass nozzle Orifice diameter (µm) Measured orifice diameter (µm) Nozzle 1 200 263 ± 0.000 Nozzle 2 150 123 ± 0.000 Nozzle 3 100 90 ± 0.000 Nozzle 4 50 65 ± 0.000 T Droplet on demand mode ± V p- p ± t a ± t p An example of a driving rectangular pulse used to generate droplets where: t a is absorption time , t p is pulsation time and V p-p is the amplitude of the pulse voltage. Tracking single droplet ta (ms) 0.01 - 5 tp (ms) 0.01 - 50 Vp (V) ± 4.5 Nozzle opening (µm) 65 , 90 , 123 & 263 Amplifier Droplet generator Tested parameters Algorithm description False Select frames for video Pass droplets with circularity between 0.7 and 1 Convert the frames into binary Noise remove Label the droplet Calculation of the droplet area and circularity True Droplet diameter and velocity Results and discussions Nozzle orifice opening (µm) Droplet diameter range (µm) Droplet velocity range (m/s) 65 134 ÷ 214 0.095 ÷ 0.805 90 242 ÷ 309 0.261 ÷ 1.250 123 312 ÷ 416 0.080 ÷ 0.684 263 389 ÷ 461 0.335 ÷ 0.772 On demand droplets produce in a repeatable way of size 134 - 461 µm with droplet ejection velocity from 0.080 – 1.250 m/s. 0.01 0.2 0.3 0.4 0.5 0.6 0.7 0.7 0.8 0.9 0.9 2 5 100 200 300 400 500 0,01 0,1 0,8 1 10 50 ta (ms) Droplet diameter (µm) tp (ms) Image background Nozzle Drople t Binary image Droplet label Droplet center location Droplet velocity Results showed dependence between the droplet initial characteristics and the pulse width and voltage amplitude. FOV : 10.5 mm x 8.4mm. Camera settings : 1000 fps at 6 µs exp.time. 1 pixel = 8.227 µm The pulse width parameters for single droplet generation differ for every nozzle. The smaller the nozzle orifice the harder the droplet generation due to surface tension at nozzle exit. The goal is to evaluate the droplet spray characteristics with a droplet generator and imaging technique.
description
Select frames for video . Convert the frames into binary. Noise remove. Label the droplet. Calculation of the droplet area and circularity. Pass droplets with circularity between 0.7 and 1. True. Droplet diameter and velocity. False. - PowerPoint PPT Presentation
Transcript of Evaluation of the spray characteristics of a single droplet with imaging techniques
Evaluation of the spray characteristics of a single droplet with imaging techniques
S. VULGARAKIS MINOV1&2, F. COINTAULT1, D. NUYTTENS2, J. VANGEYTE2, J. PIETERS3, B.HIJAZI1&2
AGROSUP DIJONINSTITUT NATIONAL SUPÉRIEUR DES SCIENCES AGRONOMIQUES DE L’ALIMENTATION ET DE L’ENVIRONNEMENT
Département Agronomie Agroéquipements Elevage & Environnement (D2A2E) 26 Bd Dr Petitjean - BP 87999 - 21079 Dijon cedex - France
+33 (0)380772348 - +33 (0)380772551 – Site Web : http://www.agrosupdijon.fr
1) AgroSup Dijon – UP GAP – 26, Bd Dr Petitjean – BP 87999 – 21079 Dijon cedex – France2) Institute for Agricultural and Fisheries Research (ILVO) - Technology and Food Science Unit, Agricultural Engineering Research Group – Burg. Van Gansberghelaan 115 – 9820 Merelbeke – Belgium 3) Department of Biosystems Engineering – Faculty of Bioscience Engineering- Ghent University – Coupure Links 653-9000 Gent - Belgium
Improvement of existing techniques Development of accurate spray quantification techniques.
MotivationPesticides Sprayers Nozzles Application accuracy and efficiency of
plant protection productsMaximization of spray efficiency and
minimizing residues and off target losses
Material and methodsImage acquisition system
Droplet generator setup: 1-Droplet generator with piezoelectric element, 2-HS camera & lens, 3-Light source, 4-PC, 5-Pressure supplier, 6- Signal amplifier, 7- Pulse generator, 8- Liquid tank.
Droplet generator
Droplet generator: 1- Glass nozzle,2-Piezoelectric element, 3-Clamp, 4-Tubes.
Glass nozzleOrifice
diameter (µm)
Measured orifice
diameter (µm)
Nozzle 1 200 263 ± 0.000
Nozzle 2 150 123 ± 0.000
Nozzle 3 100 90 ± 0.000
Nozzle 4 50 65 ± 0.000
T
Droplet on demand mode
± Vp-p
± ta
± tp
An example of a driving rectangular pulse used to generate droplets where: ta is absorption time, tp is pulsation time and Vp-p is the amplitude of the pulse voltage.
Tracking single droplet
ta (ms) 0.01 - 5tp (ms) 0.01 - 50Vp (V) ± 4.5 Nozzle
opening (µm)
65 , 90 , 123 & 263
AmplifierDroplet
generator
Tested parameters
Algorithm description
False
Select frames for video
Pass droplets with circularity between 0.7 and 1
Convert the frames into binary
Noise remove
Label the droplet
Calculation of the droplet area and circularity
True
Droplet diameter and velocity
Results and discussions
Nozzle orifice opening (µm)
Droplet diameter range (µm)
Droplet velocity range (m/s)
65 134 ÷ 214 0.095 ÷ 0.805
90 242 ÷ 309 0.261 ÷ 1.250
123 312 ÷ 416 0.080 ÷ 0.684
263 389 ÷ 461 0.335 ÷ 0.772
On demand droplets produce in a repeatable way of size 134 - 461 µm with droplet ejection
velocity from 0.080 – 1.250 m/s.
0.01 0.2 0.3 0.4 0.5 0.6 0.7 0.7 0.8 0.9 0.9 2 5
100
200
300
400
500
0,01
0,1
0,8
1
10
50
ta (ms)
Dro
plet
dia
met
er (µ
m)
tp (ms)
Image background
Nozzle
Droplet
Binary image Droplet label Droplet center location
Droplet velocity
Results showed dependence between the droplet initial
characteristics and the pulse width and voltage amplitude.
FOV: 10.5 mm x 8.4mm.Camera settings: 1000 fps at 6 µs exp.time.
1 pixel = 8.227 µm
The pulse width parameters for single
droplet generation differ for every nozzle.
The smaller the nozzle orifice the harder the droplet
generation due to surface tension at nozzle exit.
The goal is to evaluate the droplet spray
characteristics with a droplet generator and
imaging technique.
