• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.37-40
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• 2009

본 연구에서는 케로신/과산화수소 점화용 분사기의 설계/제작하여 분무특성에 관한 연구를 수행하고자 하였으며, 이에 앞서 촉매점화방식으로 적용할 때 가장 적합한 분사기를 설계하고자 하였다. 설계/제작된 분사기를 수류시험을 통해 질량 유량 및 분산각을 측정하였다. 그 결과 케로신의 목표 질량유량(12.88 g/s)은 설계 차압과 같은 차압인 3 bar에서 측정되었으며, 이 때 분산각은 $40^{\circ}$을 확인하였다. 또한 과산화수소의 목표 질량 유량(94.39 g/s)은 설계 차압(3 bar) 보다 작은 1 bar에서 측정됨을 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.43-46
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• 2002

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in-pool type, is under 24 MWth of power operation since it reached to the initial critical in February, 1995. Many useful experiments should be safely performed to activate the utilization of the HANARO, but there is a radioactive risk of using the HANARO. To reduce the risk, a test facility, which is not reacted by nuclear fuel, is being developed to simulate similar flow characteristics with the HANARO. This paper describes the computational flow analysis to determine each shape of simulating fuels for simulating the flow similarities of 36 elements hexagonal fuels assembly and 18 elements circulating fuels assembly loaded in HANARO. The shares of orifices were determined by the trial and error method and the structural integrities of them were verified by the finite element method assuming that the flow rate and pressure differences of reactor core are constant. The analysis results will be verified with the results of the flow test to be performed after the installation of this test facility.

• 대한임상검사과학회지
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• 제41권3호
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• pp.135-139
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• 2009

Pulmonary function test has been know to be greatly affected by body indices, such as sex, age, height, body weight, body surface area (BSA) and body mass index (BMI), so hat this study was focused to see the relationship between body index and flow-volume curves. Subjects were 156 (male 90, female 66) and they were examined for pulmonary function test in terms of body index and correlation/multiple regression analysis of flow-volume curves at Presbyterian Medical Center from March to August, 2009. The followings results after analyzing the correlation between body index and flow-volume curves. Although flow-volume curve FEF25-75% showed close correlation with age, body weight, and body surface area, but not with body mass index. In addition, multiple regression analysis was performed to see how each body index affects flow-volume curve FEF25-75%, and FEF25-75% dispersion was explained as 74.5% with age only, 94.2% with age and height, and 96% with age, height, and sex. Therefore, sex, age and height that are mainly used for predictive formular of pulmonary function test and nomogram were important factors for pulmonary function test itself, and further study must be done for other body index.

• Nuclear Engineering and Technology
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• 제10권2호
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• pp.79-86
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• 1978

본 연구의 목적은 수직 연료봉 집합체에서 물-공기 2상 유동일 경우 공기분포현상에 관한 실험적 데이타를 얻는데 있다. test-section은 6각형, 61개의 연료봉 집합체로 구성되며, 각 연료봉은 helical spacers로 감겨져 있고, 사용되는 유체는 공기와 물이다. 실험은 크게 2부분으로 나누어서 물의 유량을 일정하게 하고 공기의 유량을 증가시킬 경우와 물자 공기의 유량을 동시에 증가시킬 경우의 공기분포현상에 관해 실시하였다. 공기는 4구멍을 통해 각각 주입시켰다. 보이드율의 측정은 전기적 Void-needle 방법을 적용하였으며 그 결과는 도표를 통해 보여주고 있다. 이 실험의 결과로써 물의 유랑을 증가시킬 수록 공기분포는 균일하게 되며, 공기 공급 위치는 공기분포에 큰 영향을 미치고 있음이 입증되었다.

• 한국자동차공학회논문집
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• 제14권5호
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• pp.121-129
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• 2006

An Intake Port of SI engines plays a key role on improving engine performance by maximizing full load volumetric efficiency or by optimizing in-cylinder air motion. However, designing an intake port has been usually performed based on port experts' experience and know-how, which means that analytical analyses are relatively insufficient. In this paper, port design parameters which decide an overall port shape were defined in order to correlate them relevantly with flow test results accumulated so far. Test species were composed of all twenty eight SI engines which cover major engine displacements from 1,000cc to 4,000cc. First, they were tested on a steady state flow test rig to find out their flow coefficients. Secondly, those flow coefficients were analyzed based on the port design parameters measured from the engines. The most effective parameters were port height, valve head diameter, and the ratio of port size and cylinder bore diameter. The final correlation equation could predict flow coefficients within 2% deviation.

• 대한기계학회논문집B
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• 제24권6호
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• pp.880-885
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• 2000

Flow patterns and steady flow characteristics of an intake 3valve cylinder head are not obviously declared. Thus, in the study, the characteristics and limitation of intake flow coefficient which applied to multi intake valve engine are introduced. The flow coefficient and tumble characteristics are investigated by means of the steady flow test and flow visualization method. As the results, it is found that the intake flow rate is dominated by effective valve open area. In addition, this paper shows that the mass flow rate of intake 3valve engine is greater than that of intake 2valve engine and tumble flow of intake 3valve engine is superior to that of intake 2valve engine.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.180-187
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• 2017

항공기 엔진 지상 성능시험을 위한 15만 파운드 급 Test 설비를 구축하기 위해 Test Cell Type, Cell Flow, Cell Bypass Ratio, Approach Velocity, Cell Depression, Front Cell Distortion, Noise 및 Vibration 등의 주요 설계 목표를 설정 하였고, 설비 완공 후 최종 성능검사를 통해 목표 값을 충족하는 성능 데이터를 획득할 수 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.181-185
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• 2010

고체로켓모터 추진제 그레인의 핀-슬롯 표면에서의 연소로 인해 생성된 고온, 고압의 연소가스는 그레인 핀-슬롯 및 내삽노즐을 통해 외부로 방출되면서 형성되는 유동은 매우 복잡하고 다양한 형태를 가진다. 핀-슬롯형 그레인 및 내삽노즐을 가지는 고체로켓모터의 2D, 3D 스케일모델에 대한 공기유동 모사시험을 수행하였으며, 회전력 발생 등과 같은 내부유동발생 메커니즘을 규명할 수 있는 효과적인 연기-유동장 가시화 기법의 적용방법에 대한 검토가 이루어 졌다. 실험모델의 투영부를 통해 다양한 광원 및 촬영장치 방향을 이용하여, 축류 실험모델 노즐 선단부에서의 비대칭 와류튜브에 의한 선회류를 가시화하였다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.132-137
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• 2005

This research presents a modeling and a manufacturing method of screw type flow meter. This paper introduces the efficient design and manufacturing method of screw type flow meter using reverse engineering and test technology. The methods introduced this paper utilize the reverse engineering that is increasing accuracy of modeling and manufacturing of reverse model. And then it can be used in performance test with hydraulic test equipment. Hence this can be used in the basic document for development of the quite accurate flow meter.

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.797-805
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• 2003

This paper describes experimental investigations of helium-air exchange flow through single opening and partitioned opening. Such exchange flows may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with a small opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Flow measurements are made with the opening, for partition ratios H_p/H$_1$$ in the range 0 to 1. where H_p$ and H$_1$ are partition length and height of the opening. respectively. In the case of H_p/H$_1$$ of 0, flow passages of upward flow of the helium and downward flow of the air within the opening are unseparated (bidirectional), and the two flows interfere within the opening. The unseparated flow increases strength of flow resistance and therefore, the exchange flow rate is minimum through range of the partition ratios. Two flow zones, i.e., separated (unidirectional) flow zone and unseparated (bidirectional) flow zone, exist with increasing the partition length. The exchange flow rate increases with increasing the separated flow zone. It is found that a maximum exchange flow rate exists at H_p/H$_1$$ of 1. As a result of comparison of the exchange flow rates by changing the partition ratio, the fluids Interference in the unseparated zone is found to be an important factor on the helium-air exchange flow rate.