• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.44-54
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• 2018

In a spray experiment using a venturi mounted on a lean premixed LPP injector, droplets appear to have non-uniform distributions. To solve this problem, the exit angle of the venturi was changed to form a dump surface on the nozzle neck. The dump surface improved the atomization performance and minimized droplet loss while forming recirculation zone in the venturi exit. In order to solve the non-uniform spray of the injector, the flow characteristics inside the venturi and SMD of the spray are compared. Finally, an optimum venturi shape is selected to minimize the spray loss and improve the spray performance.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.66-72
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• 2020

In this study, a method for increasing the initial water supply was employed to protect the water injection nozzle by the flame when supplying the water to the steam generator. During the initial steam generator test, the flow rate was controlled by using the only venturi, but cooling water was not supplied to the combustion chamber at the beginning of combustion, thereby resulting in damage to the water nozzle. To solve this problem, a venturi and an orifice were configured in parallel to increase the initial supply flow rate to form a differential pressure between the water manifold and the combustion chamber. Venturi and orifice supply sequences were established through the water flow tests, and combustion tests were conducted for final verification. Consequently, a continuous supply of the cooling water at the beginning of combustion was achieved, and the experiment was successfully performed without damaging the cooling water nozzle.

• Journal of architectural history
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• v.21 no.4
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• pp.59-70
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• 2012

This study aims to find methodical similarities between pop art and Robert Venturi's works. Pop art and Robert Venturi's works gave attention to periodical changes and wanted to communicate with the public. This study approaches a topic from psychological viewpoints, especially visual dissonance. The results are as follows: 1. Manufactured Products ; Commercial Ornaments ${\rightarrow}$ Character Changes in Experienced Stimulation 2. Daily Elements ; Traditional Elements(Classic) ${\rightarrow}$ Contextual Effect of Canonic Representation In these cases, visual dissonance attracted a lot of public attention, and people would develop new meanings of objet. Pop art and Robert Venturi's works indicated value change in post-industrial society, therefore, this study can help to understand the correlation.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.400-405
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• 1997

산업 현장에서 널리 쓰이는 압축성 유체가 밸브 등을 통하여 원하지 않은 누설이 발생할 경우 그 배관의 외부 온도만을 측정하여 누설량을 개략적으로 구하는 방법을 보였다. 특히 배관라인등 유량 제한 요소가 없는 계통은 Fanno Line 방법을 적용하고 오리피스나 벤추리등 유량 제한 요소가 있을 경우는 노즐 모델링 방법을 적용하면 누설량을 구할수 있고 노즐모델링 방법으로 구한 누설량이 Fanno Line 방법으로 구한 누설량의 약 50%였다.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.26-32
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• 2020

In this study, a facility was constructed to supply liquid nitrogen to simulate combustion instability in a liquid rocket combustor. The pressurization and supply performances were predicted and verified through different experiments. The liquid nitrogen supply system was composed of a pressurized supply system, and a dome regulator was used to adjust the pressure of the pressurant. A cavitation venturi was used to control the mass flow rate of liquid nitrogen. The condition of liquid nitrogen supply was a mass flow rate of 2.55 kg/s and the venturi inlet pressure was above 100 bar. Based on the initial experiment, it was observed that the predicted amount of the pressurant was not sufficiently supplied and the target pressure was not supplied due to a drop in tank pressure. Through the modification of the established facilities, the target mass flow rate was successfully supplied and the cryogenic liquid nitrogen supply facility was verified.

• Journal of Internet of Things and Convergence
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• v.5 no.1
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• pp.29-34
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• 2019

A bag filter collector is a kind of air purifier that organizes several or dozens of filters to purify fine dust and release clean air into the atmosphere. If the bag filter length is less than 5m, the dust and fume attached to the bag filter could be effectively removed by passing the compressed air generated by the diaphragm valve through the venturi. Injectors that are more efficient and economical are urgently needed to achieve satisfactory results for long-bag exhaustion of more than 7 meters. In the case of existing domestic and foreign injectors, a number of blow tubes were dismantled during maintenance, and the injector and blow tube were combined to pose a number of problems, including inconvenience of work due to weight increase. In this study, injector flow for the development of the best use of interpretation of the coanda effect and the fourth round of industrial technology Intelligent automation of exhaustion, have been engineered energy than standard equipment. lowering costs and filter life to radically improve the commercial studies.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.711-714
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• 2008

The objective of this paper is to know the characteristics of pressure through a simplified typical carburetor used in small engines at the different throttle opening conditions. The carburetor is the device responsible for creating the right air-fuel mixture according to the different engine operating conditions. It is activated by the static or the dynamic pressure. The carburetor dummy is geometrically similar of LPG brush-cutter engine's diaphragm carburetor and is made of acrylic. Suction system gives body to crankcase vacuum using the vacuum pump and throttle opening conditions are controled by transfer device. Carburetor venturi throat and fuel charging tube diameter is each 20mm, 4.1mm. The result of the work presents an unprecedented phenomenon of suction pressure variation inside the carburetor venturi. It is predicted that these unprecedented pressure variation be caused by minor losses; sudden contraction or expansion, open or partially closed and so on.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.62-71
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• 2014

Three types of diffuser systems were manufactured and applied to investigate the effect of liquid fertilization of pig manure slurry by application of aeration processes. In the first type reactor, commonly used diffuser system, which diffuse air upward by diffusing aerator fixed at the bottom of the reactor is installed. In case of the second type, air diffuser is installed 10 cm above of the bottom of a reactor. In the third type reactor, the venturi-type air diffuser is installed at circulation pipe, which return pig slurry in the reactor(mixing-in-pipe process). The pig manure slurry separated to solid/liquid was flowed into the experimental reactor, and left as it for one week to precipitate solids. The concentration of organic matter, T-N, T-P and BOD in the raw pig manure slurry flowed into the reactor of bottom-fixed type aeration process were 1.82%, 4,400 mg/L, 360 mg/L and 13,542 mg/L, respectively. After aeration the concentration of organic matters, T-N, T-P and BOD in the slurry were 2.01%, 4,400 mg/L, 420 mg/L and 16,824 mg/L, respectively. The concentration of organic matter, T-N, T-P and BOD in the mixing-in-pipe type changed from 1.58%, 3,700 mg/L, 260 mg/L and 15,735 mg/L to 1.96%, 4,000 mg/L, 340 mg/L, and 18,098 mg/L, respectively. Changes of the concentration of organic matter, T-N, T-P and BOD of the pig manure slurry collected from the middle layers of two aeration reactors; bottom aeration process and the mixing-in-pipe process, were 10.4%, 0%, 16.7% and 24.2% and 24.0%, 8.1%, 30.8% and 15.0%, respectively. The thickness of foam layer generated on the surface of pig manure slurry in aeration tank was thinner in mixing-in-pipe reactor than bottom-fixed type aeration reactor.