• Journal of Drive and Control
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• v.17 no.4
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• pp.1-7
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• 2020

In orchard or crop-growing environments, pesticides are sprayed using various nozzles to prevent pests and improve productivity. Nozzles currently in use are restricted for use in multi-purpose environments, thus, it is necessary to develop new nozzles. In this study, new two-phase nozzles are proposed to improve the performance of the nozzle (flow rate, spray angle, spray particle size). The performance of the two-phase nozzles are predicted through the CFD analysis and the performance of the nozzles is compared with the experiment. The experimental results showed that the proposed two-phase nozzles are available at relatively low operating pressure condition and are capable of extensive spray particle size control. Thus, the proposed nozzles are expected to be available in various orchard environments.

• Agricultural and Biosystems Engineering
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• v.3 no.1
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• pp.29-34
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• 2002

Two charging methods of electrostatic nozzle, i.e. induction and ionized field corona charging, were designed and evaluated for orchard sprayer application. An artificial (metallic) target was constructed and used in this experiment. The charge-to-mass ratio for the induction electrode was measured by using the Faraday cage. Two conventional pressure-swirl nozzles have been employed with different orifice diameters under the same experimental operating conditions. A commercial pressure-swirl nozzle with orifice diameter of 1.0 was used for the conventional spray. The diameter of the electrostatic was 0.59 mm. The experiment was carried out for individual nozzle sprays at $0^{\circ}$, $20^{\circ}$ and $50^{\circ}$ oriented angles and three nozzles, sprayed simultaneously at a distance of 1.0 and 2.0 m from the nozzle tip to the target. The nozzles were mounted on a carriage with constant speed of 1.26 km/h with a blower attached. The weighing method was employed to evaluate for the spray deposition, ground loss and estimated drift. The results show more promising for the induction charging method, especially at $20^{\circ}$oriented angle at a distance of 1.0 m from the target for a single nozzle and when all three nozzles were operated simultaneously for spray deposition. The results of the induction charging method show promising with the developed electrostatic technique.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.302-309
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• 2010

Aerial application using an unmanned agricultural helicopter would allow precise and timely spraying. The attitude of a helicopter depends on a number of dynamic variables for roll-balanced flight. Laterally tilting behavior of a helicopter is a physically intrinsic phenomenon while hovering and forwarding. In order to balance the fuselage, the rotor should be counter-tilted, resulting in the biased down-wash. The biased spraying toward right side causes uneven spray pattern. In this study, a raised tail rotor system for the roll-balanced helicopter was studied. Thrust of the tail rotor system was measured and theoretically estimated for the fundamental database of the roll-balanced helicopter design. The estimated tail thrust and roll-moment would be used to design the raising height of tail rotor and roll balancing dynamics. The unmanned agricultural helicopter required the tail rotor thrust of about 39.2 N (4.0 kgf) during hovering with a payload of 235.4 N (24 kgf). A raised tail rotor system would compensate for the physical tilt phenomena. A further attitude control system of helicopter would assist roll-balanced aerial spray application.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.9
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• pp.34-42
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• 2010

Agricultural automation has become more and more important by environmental change. The automation demands the highest technology due to the ever changing various conditions in agriculture system. In the paper, semi-autonomous pesticide spray robot system has been developed for rose farming in the glass house. The robot is in autonomous mode during pesticide spraying process driven on pipe rail. The robot is manually driven while moving from a rail to the next rail. The drive platform and autonomous operation control system are developed based on IT fusion technology. The pesticide spray system is also developed with nozzles and booms for precision mist spray system. Experimental data of nozzle test is also included.

• Journal of Biosystems Engineering
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• v.20 no.3
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• pp.217-225
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• 1995

This study was conducted to find design factors of spraying device of the boom sprayer for low volume application. Four types of nozzles(standard flat nozzle, drift guard nozzle, even flat nozzle, and hollow cone nozzle) were used for the spray characteristic experiment. Spray patterns of the nozzles were distinguished by the nozzle type, spray distance, and spray direction. The flow rate was proportional to the square root of spray pressure in all nozzles. Increased nozzle height improved spray distribution at reduced pressures and/or increased spacing. Distribution tended to improve as pressure increased within the range of pressures used for fan nozzles.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.259-262
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• 2011

In organic Chinese cabbage fields, Commercial Bacillus thuringiensis products are used widely against diamond back moth, Plutella xylostella. We conducted the study to determine the effective spray-interval of commercialized B. thuringiensis against diamond back moth on Chinese cabbages. Chinese cabbage leaves were collected 0, 1, 2, 3, 6, 10days after treatment in first trial and 0, 2, 4, 7, 9, 11days after treatment. We compared the insecticidal property of sprayed B. thuringiensis and the density of it on surface of Chinese cabbages using collected leaves. The insecticidal property maintained high until nine days after commercial B. thuringiensis products sprayed.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.264-270
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• 2016

This study was conducted to compare of the pesticide residue amounts in fruit trees applied by different sprayers and spray volumes. Apple tree was used as a sample tree, and speed sprayer, power sprayer and knapsack motorized sprayer were tested. For similar sprayer and spray volume, the concentration of fluquinconazole and flusilazole in apple leaves were obtained respectively, for speed sprayer 8.33 and 2.15 mg/kg, for power sprayer 4.56 and 1.10 mg/kg, and for knapsack 4.55 and 1.12 mg/kg. The results showed that the treatment using speed sprayer had highest efficiency. The pesticide residues in apple leaves sprayed by 3 different spray volumes (560, 336 and 230 L/10a) using speed sprayer were 10.76 mg/kg, 8.32 mg/kg, 6.04 mg/kg on fluqinconazle and 3.04 mg/kg, 2.14 mg/kg and 1.47 mg/kg on flusilazole, respectively, indicating that the higher the volume, the higher the residues. The results from this study can be used as scientific basis for evaluating the field trial data for pesticide registration and the spray volume setting for fruit trees in Korea.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.06b
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• pp.35-41
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• 1998

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.02a
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• pp.215-220
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• 2000

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.514-521
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• 2010

Fertilizers, plant growth promoting microbes and plant growth regulators should be combined together and used in order to achieve a maximal plant growth and yield in modern sustainable and ecological agricultural systems. In this study rhizosphere inoculation of Methylobacterium oryzae CBMB20 and foliar application of methanol were tested for their ability to promote the growth of red pepper plant at different levels of organic fertilizer. Rhizosphere inoculation of M. oryzae CBMB20 and foliar spray of methanol could promote red pepper plant growth and yield, and the growth promoting effect induced by the combined treatment of M. oryzae CBMB20 inoculation and foliar spray of methanol was more distinctive. This result suggests that a synergistic growth promoting effect of methanol spray and M. oryzae CBMB20 inoculation can be obtained in the combined treatment of the two growth promoting factors. The growth promoting effect was more significant in the lower fertilization rate, and the plant growth was not significantly different between 100 and 300% fertilizer treatments where both M. oryzae CBMB20 inoculation and foliar spray of methanol were included. This result indicates that, with the plant growth promoting effect of M. oryzae CBMB20 and methanol, fertilizer application rate can be profoundly reduced without any significant decreases in biomass accumulation and yield of crops.