• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.974-979
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• 2004

The fluidic muscle cylinder consist of an air bellows tube, flanges and lock nuts. It's features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. In this study, we carried out the finite element modelling and analysis about the main design variables such as contraction ration and force, diameter increment of fluidic muscle cylinder. On the basis of finite element analysis, the prototype of fluidic muscle cylinder was manufactured and tested. Finally, we compared the results between the test and the finite element analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1963-1967
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• 1996

This paper describes the analysis, design, and silicon-fabrication of a fluidic proportional amplifier, which is the most important element of fluidic logic circuits. First, FEM(finite element method) analyses were performed, using the Fluent computational fluid dynamics program, and design geometries were optimized. Then, a $40\;{\mu}m$-deep amplifier was fabricated in silicon using anisotropic dry etching.

• 한국정밀공학회지
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• 제21권1호
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• pp.87-93
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• 2004

Recently, with the development of bio-technology the interests in the micro-fluidic devices for analysis in the fields of biology and medical science have been steadily increasing. Although polymer is considered as one of the best materials for micro-fluidic devices. glass or silicon molds fabricated by photo-lithographic technique have been commonly used. However, it is generally perceived that the conventional photolithographic technique has the limitation for fabricating micro-channels for micro-fluidic devices. In this work, the possibility of fabrication of micro-fluidic channels on PDMS by using the mechano-chemical process and the effect of surface states on the fluid flow were investigated. Experimental results revealed that PDMS mold fabricated by the mechano-chemical process could be used effectively to replicate micro-fluidic channels with high reproducibility and dimensional accuracy. It was also found that the fluid flow generation and flow speed were largely affected by the hydrophilicity and the surface roughness of the micro-channel surfaces.

• Nuclear Engineering and Technology
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• 제51권5호
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• pp.1279-1288
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• 2019

The vortex-type fluidic diode (FD) is a key safety component for inherent safety in various advanced reactors such as the sodium fast reactor (SFR) and the molten salt reactor (MSR). In this study, topology optimization is conducted to optimize the design of the vortex-type fluidic diode. The optimization domain is simplified to 2-dimensional geometry for a tangential port and chamber. As a result, a design with a circular chamber and a restrictor at the tangential port is obtained. To verify the new design, experimental study and computational fluid dynamics (CFD) analysis were conducted for inlet Reynolds numbers between 2000 and 6000. However, the results show that the performance of the new design is no better than the original reference design. To analyze the cause of this result, detailed analysis is performed on the velocity and pressure field using flow visualization experiments and 3-D CFD analysis. The results show that the discrepancy between the optimization results in 2-D and the experimental results in 3-D originated from exclusion of an important pressure loss contributor in the optimization process. This study also concludes that the junction design of the axial port and chamber offers potential for improvement of fluidic diode performance.

• 에너지공학
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• 제14권1호
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• pp.54-61
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• 2005

한국형 신형원자로1400(APR1400)은 3983MWt급의 2×4 루프 개량형 가압경수로(PWR)로서 대형 냉각재상실사고 발생시 안전주입수의 원자로용기 직접주입(DVI) 방식을 채택하고 있으며, 안전주입수탱크(SIT) 내부에 유량조절기(Fluidic Device, FD)를 장착하고 있다. 본 연구에서는 신형원자로 1400의 안전주입계통에 새로이 적용된 주요 특징 중 하나인 유량조절기에 대하여 최적안전해석코드인 TRAC-M/F90, 3.782버전을 이용한 성능평가 및 민감도 분석을 수행하였다. 연구결과 유량조절기가 안전주입수의 원자로 유입을 적절하게 조절하고 있음을 확인하였으며, 안전주입수탱크 내부의 압축질소체적 감소가 안전 주입수체적 감소에 비하여 노심의 급냉 완료 시점을 빠르게 하였다. 또한 안전주입계통의 전체 저항계수(K factor)가 최소 또는 최대일 때 노심의 급냉 완료 시점은 평균값인 경우보다 다소 늦어졌으나, 피복재 최고온도(PCT)는 상대적으로 큰 차이가 발생하지 않았다.

• 오토저널
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• 제3권2호
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• pp.34-42
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• 1981

The feasibility of using fluidic components for improving certain performance characteristics of the suspension systems for tracked vehicle is investigated. This study describes three variable damping systems for which the damping coefficients are function of relative velocity and absolute a of the vehicle body. Through the comparison analysis between constant damping coefficient damper and each of variable dampers. the followings were found: (1)Fluidic Diode Damper gave less accelerations, (2)Both Fluidic Diode Damper and Relative Velocity Damper gave the less time for which the wheel is off the ground, (3) At low vehicle velocity Fluidic Diode Damper gave low energy dissipation rate, while at high vehicle velocity Turbulence Accelerometer Damper gave low energy dissipation rate.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2005년도 춘계 학술대회
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• pp.134-138
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• 2005

Recently many researches related with biotechnology are processed and it is the situation that research about micro fluidic devices is active. Micro fluidic devices has been one of the most widely used devices for the analysis in biotechnology because they have many advantages, flexibility, transparency, thermal and electrical stability, nontoxic, etc. In this study, micro fluidic device with PDMS is developed for particle counter which separates a small quantity of particles, The principle of micro particle counter is electrical-impedance method, and it was also applied hydrodynamic flow focusing. It is more efficient method to analyzing particles furthermore it can be applied to cell count ins for biotechnology.

• Design & Manufacturing
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• 제15권2호
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• pp.56-62
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• 2021

In this study, design technology of a non-mechanical flow meter using fluidic oscillation generated during the fluid flow in the chamber was investigated. To with respect to design a splitter, which is the most important factor in fluid oscillation, a transient flow simulation analysis was performed for three types of shapes and changes in inlet flow velocity. The oscillation characteristics with respect to the time in each case were compared, and it was confirmed that the SM03 model was the best among the presented models. In addition, the FFT analysis of the fluid oscillation results for the SM03 model was used to obtain a linear correlation between the flow velocity change and the maximum frequency, and a frequency of 20.957 (Hz/m/s) per unit flow velocity was obtained. Finally, injection molding simulation and molding experiment of the chamber with the designed splitter were performed.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.123-127
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• 2009

기계적 제어장치를 사용하지 않으면서도 추력방향 제어가 가능한 유체역학적 추력편향제어(Fluidic Thrust Vector Control; FTVC)기법에 대한 연구 논문이다. 2차 유동은 주 유동 흐름과 같은 방향으로 분사하였고, 선행연구를 통해 정상(steady)상태의 수치해석 결과는 실험과 비교 검증하였다. 이를 바탕으로 비정상(unsteady) 수치해석을 수행하였고, 위아래로 제트가 편향이 될 때에 소요되는 시간과 벽면에서의 압력 분포 등을 조사하여 추력벡터의 동특성을 연구하였다.

• 한국추진공학회지
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• 제20권3호
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• pp.103-110
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• 2016

유동 제어 시스템에 적용을 위한 디스크형 유체 소자 밸브의 성능해석 알고리즘을 수립하고 설계 변수들에 대한 민감도 분석을 진행하였다. 유입 유량 발생에 따른 챔버의 압력 변화와 디스크 거동 변화를 예측 하였고 설계 변수들의 민감도 분석을 위해 Scattering plot 기법을 활용하였다. 민감도 분석결과 유동 마하수에 가장 큰 민감도는 갖는 변수는 노즐 출구이며 밸브 응답 시간과 노즐 출구 모두에서 큰 민감도를 갖는 변수는 유입 유량임을 확인하였다.