• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.258-264
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• 2017

Purpose: This study determines the spray characteristics and effective spray width of a tractor-mounted commercial boom sprayer through experiments. Methods: Performance tests were conducted to investigate the spray characteristics of the nozzles on a commercial boom sprayer. The flow rate and spray width of a single nozzle were measured at three levels of spray pressure (0.5, 0.7, and 1.0 MPa) and spray height (15, 30, and 45 cm), respectively. The average value of three repetition tests was used as the representative value. A coefficient of variation (CV) was used as an index of spray uniformity, and the width that guarantees CV values of approximately 15% was determined as the effective spray width. The spray characteristics of the overall boom sprayer were derived analytically by superimposing the spray characteristics of a single nozzle. Results: The test results for a single nozzle showed that the spray width tended to increase as the spray height and spray pressure increased. The effective spray width for a single nozzle was the largest at a spray pressure of 1.0 MPa and spray height of 45 cm, which resulted in a coverage of 84 cm of width. The effective spray width for the entire boom sprayer was also the largest at the spray pressure of 1.0 MPa and spray height of 45 cm, with a magnitude of 424.5 cm. The chemical spraying work in an actual field was simulated by applying a spray width of 400 cm. As a result of the operation for three swaths, the CV value was less than 10% for 1,200 cm of the overall spray width, which meant that uniform application was achieved. Conclusions: It was reasonable to set the effective spray width of the boom sprayer used in this study to 400 cm.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.575-580
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• 2023

This study was prevent the decrease in crop output by insect pests and spraying by application uniformity. A flight level 4 m height and 4-5 m/sec. speed are difficult to maintain with a agricultural drone for aerial application, which has been affected by the methods or environmental factors, such as changes in the wind. Therefore, which can allow a controlled application width and spray rate automatically and verified experimentally using drone. The sprayed particles began to decrease from about 3.75 m on the left and right sides of the spray nozzle. According to the number of particles, the effective spraying width was observed to be about 7.5 m, and it was verified that the proposed spraying system was effective in uniform control system.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.905-909
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• 2003

This paper describes a shower type ultrasonic cleaning system using particle acceleration, developed for better effectiveness in washing out agricultural chemicals from fruits or vegetables, compared to the existing bath type ultrasonic cleaning system. The shower type system consists of a signal generator, a transducer, and a spouting nozzle, mainly. The system has been tested based on the method recommended by Korea Food and Drug Administration. It is found that shower type system shows better performance and cost-effectiveness than the bath type system that is commercially available .

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.22-27
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• 1999

최근 정밀농업기술의 중요성이 인식되면서 점살포, 직접살포, 또는 방제목표물의 크기에 따른 분무량 조절 등의 기술이 개발되고 있으나 모든 기술이 분무량 조절에만 치중되어 있다. 일반적인 수압식 노즐의 경우에 분무압을 이용하여 분무량을 제어하면 분무입자의 크기가 적정 이외의 크기로 살포되어 효율적인 방제효과를 얻기가 어렵다. 하나의 제어인자 즉 분무압만을 이용하여 두 가지의 특성 즉 분무량과 분무입자의 크기를 조절하는 것은 이론적으로 불가능하다 정밀방제에 있어 분무입경과 분무량을 독립적으로 조절할 수 있으려면 두 가지 제어인자를 가진 노즐을 이용해야만 가능하며 이러한 범주에 속하는 노즐로는 원심노즐과 이류체노즐, 정전화노즐 등이 있다. (중략)

• International Journal of Automotive Technology
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• v.2 no.3
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• pp.103-107
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• 2001

Many researches on pressure-swirl injectors due to the variety of application have been conducted on the effects of nozzle design, operating conditions, properties of liquid and ambient conditions on the flow and spray characteristics. The breakup length of conical emulsified fuel sheet resulting from pressure-swirl atomizer using in the oil burner was investigated with the digital image processing method with neat light oil and emulsion with water content of lotto% and the surfactant content of 1-3%. The injection pressure ranged from 0.1 to 1.2 MPa was selected. The various regimes for the stage of spray development within the experimental conditions selected in this study is newly suggested in terms of Ohnesorge number and injection pressure. The breakup length for both criteria show the same tendency even though the random nature of perforation and disintegration process of liquid sheet. The stage of spray development is widely different with the physical properties of liquid atomized, mainly viscosity of liquid. The breakup length decreases smoothly with increase in the injection pressure for the lower viscous liquid.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.418-422
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• 2003

농가에서는 재배하고 있는 과채류는 접목하지 않은 실생묘를 육묘하여 사용하거나 공정육묘장에서 실생묘 혹은 접목묘를 구입하여 사용하고 있으며, 특히 접목묘의 경우는 거의 대부분 공정육묘장에서 육묘된 모를 사용하고 있다. 수박, 오이, 참외의 박과채소는 연작장해의 피해를 줄이고 만할병을 방지하며 저온신장을 도모하기 위해서 접목재배를 많이 실시하고 있다. 또한 터널이나 노지 재배의 경우에는 접목을 하게되면 내습성을 높일 수 있다. 참외의 경우에는 세근이 많이 발달하지만 흡비력이 약하다. 그러나 대목으로 쓰이는 호박은 뿌리의 발달이 왕성할 뿐만 아니라 흡비력이 강하다. (중략)

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.6
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• pp.83-89
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• 2000

A depot encircled with contact oxidation canal has been developed to improve water qualityr. The depot is aimed to settle suspended solid in the flow. The oxidation canal is to contact the pollutants and oxygen in the surface of gravel filter to purify the water. The deposit of the pollutant in the depot is released by the drainage culvert located at the bottom of it. Aeration nozzle is installed to supply enough oxygen to the gravel filter layers in the bottom of the detent the flow and improve oxidation efficiency. From the experiment it is founded that 91% of SS, 39% of TN, 63% of TP and 77% of COD were removed in the system. The treatment efficiency of total nitrogen is rather lower than any other components, however, it would be higher when some floating vegetation is added in the primary clarifier. The depot and oxidation canal system would be useful to purify the flows in the mouth of the reservoirs or at the outlet of the drainage canal.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.404-410
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• 2009

This study was carried out to develop a self-propelled type explosive subsoiler for improving the root zone soil conditions in orchard and other forest fields. Prototype was designed to be able to inject air and other soil improving material such as lime into soil at the same time, and thus improve the air permeability and drainage of orchard soils to promote the root growth of tree for high quality fruit production. Soil penetration device of explosive subsoiler is composed of air hammer, penetration rob and air injection nozzle. To support the soil penetration device of explosive subsoiler to penetrate vertically, modified Scott-Russel mechanism was used. Timing control device for simultaneous injection of soil improving material with air was attached to the out side wall of air cylinder and as the cylinder move, the soil improving material was injected into soil at the same time. Turning radius of prototype was 2.2-2.3 m with good mobility in sloped land. It took approximately 1 minute for lime injection system to reach the optimum pressure of 9.9 kg/$cm^2$, average 10-20 seconds were required to rupture soil with the depth of 50 cm and 2-3 seconds were required for explosion, so all in all about 1 minute and 20 seconds were required for one cycle of explosion. Maximum soil rupture depth and diameter were 50 cm and 3-4 m respectively depending on the soil type and soil moisture content. For final design of explosive subsoiler inclination angle of lime hopper was increased from 60 degree to 70 degree and the shape of hopper was changed from rectangular cone to circular cone to solve the clogging problem of lime at out let. Agitating system operated by compressed air was attached to the metering device of the prototype, thus more than 90 cc of lime was discharged per cycle from metering device without clogging problems.

• Journal of Biosystems Engineering
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• v.13 no.3
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• pp.1-10
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• 1988

Fraser, Dombrowski, Tanasawa 그리고 Momono 등(等)이 분구(噴口)에 대(對)한 중자도구(中子導溝) 단면적(斷面積)의 비(比)에 기초을 두고 있는 Nozzle Parameter가 클수록 유량계수(流量係數)는 증가(增加)한다고 보고(報告)하였다. 그러나 노즐의 구조(構造)는 중자도구(中子導溝) 및 와실(渦室)의 형상(形狀)에 따라서 특성(特性)을 가지고 있고 구조(構造)의 특성(特性)은 유량계수(流量係數), 분무각(噴霧角) 및 살포도(撒布度)에 지대한 영향을 미친다. 노즐구조(構造)에 관(關)한 이론분석(理論分析)의 결과(結果)는 다음과 같다. 중자도구변(中子導溝邊)(d), 중자(中子)두께(t) 및 중자도구각(中子導溝角)(${\theta}$) 등(等)의 관계(關係)가 와실유선각(渦室流線角)(${\theta}_c$)에 미치는 영향은 $$tan({\theta}_c)=\frac{t{\cdot}sin^2{\theta}}{d-t{\cdot}sin{\theta}{\cdot}(1-cos{\theta})}$$ 또한 와실유선각(渦室流線角)(${\theta}_c$)이 중자도구각(中子導溝角)(${\theta}$)과 일치(一致)하는 관계(關係)는 $\frac{d}{t}=sin{\theta}$이다. 와실유선각(渦室流線角)과 와실형상(渦室形狀)과의 관계(關係)는 $$tan({\theta}_c){\qeq_-}\frac{r_c-r_g}{L_c}$$ 이며 와실유선각(渦室流線角)은 와실유선회전반경(渦室流線回轉半徑)과 와실(渦室)길이의 비(比)에 의(依)하여 변화(變化)함을 시사(示唆)한다. Swirl core가 Swirl plate보다는 생산비(生産費)의 고려없이 압력손실(壓力損失) 및 마찰손실 면(面)에서 더욱 합리적(合理的)으로 고려(考慮)된다.

• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.245-252
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• 1998

The structural characteristics of a small scale rice polisher was analyzed to improve its performance. Spraying characteristic of nozzles used for rice polishing was also analyzed by a machine vision system. The internal pressure of the polishing chamber was measured according to outlet resistance, water spraying, and roller shaft speed. In addition, the performance of the rice polisher was evaluated to improve it in the basis of internal pressure in polishing chamber, whiteness, and broken rice ratio of clean rice according to the operating conditions. Actual nozzle discharge rate and drop size were 125 cc/min and 86~97 ${\mu}{\textrm}{m}$, respectively. In the case of water spraying on rices, the internal pressure showed 4.9~9.8N/$\textrm{cm}^2$ increase. broken rice ratio decreased, and there was no difference in whiteness. The internal pressure inueased up to two times with the increase of the outlet resistance. Also, the pressure at the upper part of screen was one and half times as high as the pressure at the lower part. In the case of water spraying rate of 150 cc/min, the roller shaft speed of 850 rpm resulted in no difference in whiteness and decrease of 0.3% in broken rice ratio, comparing to the roller shaft speed of 950 rpm.