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Jiang Yiyuan, Professor, et al.
Northeast Agricultural University (NEAU), China Agricultural Academy,
People’s Republic of China

PROGRESS IN MECHANIZATION OF CONSERVATION CULTIVATION
OF ROW CROPS AND RISE AS AN EFFICIENT SOIL EROSION CONTROL
MEASURE ON THE NORTH-EAST OF CHINA

Summary

The paper presents the technological principles and designs of tractor/implement sys-
tems of various types for soil tillage, precision and single-seed planting of soybean and maize,
and also flexible floating cutter bar of low cut for soybean harvesting, attached to grain com-
bine harvester header.
The substantial economic effect was obtained owing to the soybean yield premium,
high performance of machines and equipment and lower soybean loss.




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Tiansheng Hong, Professor
Polytechnic College, South China Agricultural University, Guangzhou 510642,
China, tshong@scau.edu.cn
Wanzhang Wang, Associate professor
Mechanical and Electrical Engineering College, Henan Agricultural University,
Zhengzhou 450002, China, wzwang@263.net

PESTICIDE DISTRIBUTION TEST OF THE HYDRAULIC NOZZLE
FOR PROFILE MODELING SPRAY *

ABSTRACT. With the aim of achieving a quality product and with consideration for
the environment, the pesticide distribution test system for profile modeling spray was estab-
lished. The system mainly consists of the spray controller, garden spray machine, spray distri-
bution test stand and the conveyer. In order to increase the spray deposition in canopy, to im-
prove the spray coverage and to reduce the loss of pesticide out of the tree, the spray experi-
ments were conducted for a type of hollow cone nozzle horizontal installed to study its
solution distribution model and find the spray operating parameters. The effects of the spray
pressure and the travel speed on the solution distribution were investigated. Hence this paper
provides the main fundamental data for profile modeling spray research.
KEYWORDS. Fruit tree, Pesticide distribution, Hollow cone nozzle, Profile modeling
spray

INTROUDUCTION
Pesticide spraying is still the most effective and economical way of controlling the
plant diseases and insect pests in the fruit tree growing. But the chemical application in or-
chard was considered as the problem of pollution. So there has been a trend over many years
to reduce the amount of pesticide spray in fruit tree. To meet the requirements of modern
plant protection as well as stricter ecological standards, the new technology of the pesticide
spray must be developed to spray efficiently and safely. Orchard sprayer must ensure ade-
quate chemical deposition on the target with minimal spray loss. A significant contribution
come from improvements in spray application technology was the ultrasonic sensor being
used. Based on the ultrasonic sensor, the spray was able be controlled as the tree present, so
called Selective spray. The objctive of paper is to study the pesticide distrbutin from the
hydraulic nozzle to realize the most efficiciency deposition depend on the proefile modeling
spray base on the ultrasonic sensor.
Proefile modeling spray’s working principle is realizing the precise pesticide spray
work according to the actual shape of fruit trees. It applies modern control and electronic-
informational technique to the plant protection machines. The method can increase the utility
ratio of pesticide, while can minis loss of liquid pesticide and can reduce the environmental
pollution and pesticide leftover on the fruit surface, so the precise spray can be realized.
For the profile modeling spray of fruit tree, the distance from the hydraulic nozzle to
the tree’s canopy is the key operating parameter because of the distribution of the pesticide
solution. But there are many factors that effect on pesticide distribution, such as spray pres-
sure; spray ground speed etc. So a test system is built to investigate the distribution of the
hydraulic nozzle selected for the profile-modeling sprayer.


*
This research work supported by the National Natural Science Foundation of China (NSFC)
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TEST SYSTEM OF THE PROFILE MODELING SPRAY
The test system consists of four major parts: The garden spray machine (ZXA6,
Meizhou China) with a pump (2.0-4.5Mpa) and a 500L tank, the conveyer that drive the noz-
zle move in different speed (See Fig. 1), the spray distribution test stand consisting of “V
shaped “ channels and the spray test controller.




Fig. 1. Nozzle translation control conveyer


In this test system the components to be controlled are two frequency converters and a
solenoid-controlled valve. Two frequency converters change two three-phase AC motors
speed respectively. One is the spray pump motor. By changing the speed of the spray pump
motor the spray pressure can be adjusted. Other is the motor that drives the sprayer traveling.
An ultrasonic sensor (Model No. PS1L-D1M Fuji Co. Japan) is used to achieve the distance
from the nozzle to the tree. The key component in this spray test controller is a single-chip
micro controller (Model AT89C52). It is an enhancement type in MCS-51 series, with 8K
ROM, 256B RAM and three timers. Hence the foundation is provided for the realization of
the function of the spray system. The architecture of the test control system is shown in Fig.2.
In this system two analogue-to-digital channels for the signal of ultrasonic sensor and pres-
sure transducer are offered by the ADC0832 series A/D converter. A D/A converter provided
four digital-to-analogue channels and offers two for the two frequency converters. To store
and forward the experiment data, The E2PROM - AT93C46 with 1kbit memory and a RS-232
interface for computer communication are used. The out put signals are sent to the electro-
hydraulic valve through the input/output ports. The circuit has a keyboard and a liquid crystal
display screen.
With this test system the spray pressure, volume of the spray solution and the range
from the turn spray on to off can be controlled when the spray distribution experiment. The
spray test was conducted indoor for two hollow cone nozzle (Model: 1/4MKB80200BCV-
RW and 1/4MKB80320BCV-RW, VMD 130?m and 210?m, Ikecuchi, Japan, Abbreviated to
200 and 320 in the following text) to study its solution distribution. Clean water substitute for
the pesticide solution in the spray distribution experiments.




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Variable Pump motor
Ultrasonic Sensor
Frequency
driver

Pres ? sure




Ship Microcomputer System
Sensor Three phase Travel switch
power
supply
Volume Sensor



Variable Traveler motor
Photoelectric
Frequency
switch
driver

Switching Power Electro- Direct current
Supply hydraulic source
valve


Figure 2. Structure of spray test control system

PESTICIDE DEPOSITION EXPERIMENTS
A group of orthogonal experiment is done by some different spray parameters to work
out their influences of the average spray range of liquid pesticide deposition on the stand un-
der the indoor environment. Table 1 shows the factors and the level of the orthogonal experi-
ment are shown in table 1.
Table 1
Combination of the orthogonal experiments parameters

Levels
Factors
1 2
A/Pressure/ MPa 1.20 2.00
B/Travel speed /km/h 3.30 0.51
C/Nozzle/Model 200 320

The average spray range can be calculated from

n x ivi
?
D=
n
i= 1 ? vi
i= 1

Where
D = average spray range (mm); i =“V-shaped” channel number of the spray test stand
(i= 1,2,3,……n); Vi = Volume of the liquid deposited from No. i channel (ml); xi = Dis-
tance from nozzle to the No. i channel (mm)
The extreme difference analysis of test results is shown in table 2. The conclusion we
drew out is that, under the indoor environment, the nozzle model (Different in the volume
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ISBN 5-88890-034-6. Том 1.


median diameter of droplets), the travel speed and the pressure effect the pesticide distribution
significantly. To further investigate the effects of the spray pressure and the travel speed on
the solution distribution, the spray pressure test and travel speed test are conducted respec-
tively.
Table 2
Analysis of variance dependent variable of average distribution range

SourceSum of Square D.FMean Square F valueConspicuous level
A 21595.62 1 21595.62 55.47 0.08
B 22278.44 1 22278.44 57.22 0.08
A?B 5757.18 1 5757.18 14.79 0.16
C 35007.90 1 35007.90 89.91 0.07
A?C 4016.32 1 4016.32 10.32 0.19
B?C 2236.80 1 2236.80 5.75 0.25
Error 389.34 1 389.34
Total 91281.60

The spray pressure experiment shows that with the increase of the pressure the average
deposition distance increase proportionately (See Fig.3 and Fig.4). AS the spray pressure in-
crease from 0.67 to 2.38Mpa, the average deposition distance of the two nozzles selected in-
crease 464mm and 391mm respectively.
1600
Average range /mm




D = 313. 25P + 851. 16
1500 2
R = 0. 9576
1400
1300
1200
1100
1000
900
800
0 0. 5 1 1. 5 2 2. 5
S p ra y p re s u re /MP a
Fig . 3 Averag e depos ition dis tance with the
increas e of s pray pres s ure for nozzle 2 0 0


1500
Average range /mm




D = 203. 01P + 1009. 1
1400 2
R = 0. 9634
1300

1200

1100

1000
0. 00 0. 50 1. 00 1. 50 2. 00 2. 50
S p ra y p re s u re /MP a
Fig . 4 Averag e depos ition dis tance with the
increas e of s pray pres s ure for nozzle 32 0


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The experiment results show that with the increase the sprayer ground speed the aver-
age deposition distance of two nozzles decrease (See Figure 5 and Figure 6). The speed in-
crease from 0.51 to 4.0km/h, the average deposition distance of the nozzle 200 and 320 de-
creases 251mm and 173mm respectively.

Average range /mm 1000
Nozzle 200
Pressure 1.2Mpa
900



D=- 67. 022V+997. 79
800
R2=0. 9625


700
0. 00 1. 00 2. 00 3. 00 4. 00
Speed / km/h
Average range /mm




1200
Nozzle 320
Pressure 1.2Mpa

1100




1000 D 43. 466V+1142. 3
=-
2
R =0. 8544


900
0. 00 1. 00 2. 00 3. 00 4. 00
Speed / km/h
Fig. 5 Relationship between average
deposition distance and travel speed

For further computerizing the spray solution distribution, the fitted lognormal distribu-
tion function was built based test datum. If the minimum deposition distance is defined as the
distance when the cumulative probability not greater than 0.1 and the maximum deposition
distance is defined as the distance when the cumulative probability not less than 0.9, the rela-
tionship between the spray deposition rang and the spray operating parameters such as pres-
sure and speed can be calculated. Fig. 6 and Fig.7 are the relationship between the maximum
and minimum deposition distance of the nozzle 200 and its spray pressure and travel speed
respectably.
As it can be seen from the Fig.6 and Fig.7 that the variation of minimum deposition
distance D(0.1) is not great than the maximum deposition distance D(0.9) when the spray
pressure and travel speed increases. The distance from the nozzle to the canopy can be set
according the minimum deposition and keep constant distance when the spray operation. The
deposition range increase when the spray pressure increase, because the maximum deposition
distance increase greatly. And the deposition rang decrease when the travel speed increase,
because the maximum deposition decrease greatly. Hence the travel speed and spray pressure
should be adjusted depend on the diameter of the fruit tree.
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ISBN 5-88890-034-6. Том 1.




Distance / mm
3000

2500

2000

1500

1000

500
D(0.1) D(0.9) D(0.5)
0
0 0.5 1 1.5
2 2.5
Pressure /MPa
Fig. 6 Deposition distance from nozzle 200 with the
pressure increase
Distance /mm




1600
1400
1200
1000
800
600
400
D(0.1) D(0.9) D(0.5)
200
0
0.0 1.0 2.0 3.04.0 5.0
Speed / km/h
Fig.7 Deposition distance from nozzle 200 with the
travel speed increase


DISCUSSION AND CONCLUSION
Selecting a hydraulic nozzle for the target detecting spray system in the orchard
spraying is an important work in sprayer design. Deposition distance experiment for the
selected nozzles could be conducted to find out its basic operating parameters. Because the
foliage dence of canopy is not considered in this indoor experiment the further calibration
should be carred in practice.
The spray pressure and the travel speed are the key parameters that effect on the spray
deposition distance. The average deposition distance increase with the pressur increase and
decrease with the travel speed increase. Based on the test syetem not only the volume of
pesticide solution be measured, but also the range of the spray deposition could be specificed.
The experiment bring forward the control way of the pestcide desposition from the
hydraulic nozzle in profile modeling spray. The distance from the nozzle to the canopy
depend on minium deposition distance. The spray pressure and the ground speed should be
controlled to fit the canopy size of fruit trees.



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ISBN 5-88890-033-8. Экология и сельскохозяйственная техника. СПб, 2005.


REFERENCES
Bill A Stout. 1999. CIGR Handbook of Agricultural Engineering (Volume III). CIGR-
The International Commission of Agricultural Engineering. American Society of Agricultural
Engineers
Molto E, Martin B, Gutierrez A. 2000. Design and testing of an automatic machine for
spraying at a constant distance from the tree canopy. Journal of Agricultural Engineering Re-
search. 77(4): 379-384
Grzegorz Doruchowski,Ryszard Holownicki.2000.Environmentally friendly spray
techniques for tree crops. Crop Protection. (19): 617-622
Cross J V, Walklate P J, Murray R A et al. 2001. Spray deposits and losses in different
sized apple trees from an axial fan orchard sprayer: 2. Effects of spray quality. Crop Protec-
tion. (20): 333-343
Mechrdad Darvishvand Taher. 1998. A virtual nozzle for pesticide spray deposition in
a plant canopy PhD diss. The university of Guelph
Wang Guien. 2003. Profile modeling spray mechanism and its technology foundation
for fruit trees. Unpublished PhD diss. Guangzhou, South China Agricultural University, Col-

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