• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.46-48
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• 2008

나노복합 블레이드가 반도체 웨이퍼 가공을 위한 마이크로급 나노장치나 그 이상의 나노급 구조체를 위해 사용되었다. 금속 블레이드는 실리콘 웨이퍼 가공을 위해 사용되어 왔다. 그러나, 최근 레진 복합 블레이드는 반도체나 핸드폰의 쿼츠 웨이퍼 가공에 사용된다. 유기 또는 비유기 재료 선정은 기계가공성, 전기 전도성, 강도, 연성 및 웨이퍼 저항을 가진 블레이드를 만드는데 중요하다. 고성능 응용의 증대 요구에 따라 개발된 고기술 비유기성 재료의 혼합은 낮은 가격에 고기능의 신뢰도를 필요로 한다. 나노 입자의 크기를 가진 레진 복합물의 마이크로 설계는 입자간 상호작용의 제어가 필요하다. 형상 제작 동안 마이크로 차원에 두께를 유지하기 위해서는 마이크로/나노급 제작을 위한 가공기술이 중요한 것 중의 하나이다. 본 연구에서는 핫 프레스 구조물이 원래 설계 기준과 두께 차이의 실험 접근법을 사용해 만들어졌다. 다른 습식 공정 기술은 차원의 허용치를 개선하기 위해 만들었다. 실험들과 해석들은 신뢰성 결과가 사용가능함을 보여주었다. 반도체 시장에 사용될 레진 복합 블레이드의 개선 효과가 논의되었다.

• Journal of Aerospace System Engineering
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• v.12 no.3
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• pp.58-63
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• 2018

This work dealt with the design and manufacturing of composite blades of a vertical axis wind turbine system. In this work, aerodynamic and structural designs of sandwich composite blades for a vertical axis wind turbine system were performed. First, the aerodynamic and structural design requirements of the composite blades were investigated. After the structural design was complete, a structural analysis of the wind turbine blades was performed using the finite element analysis method. It was performed with the stress and displacement analysis at the applied load condition. A design modification for the structurally weak part was proposed as a result of the structural analysis. Through another structural analysis, it was confirmed that the final designed blade structure is safe.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.3
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• pp.57-68
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• 2012

In this study, designs of the high efficiency composite propeller blade for a high speed turboprop aircraft, which will be used for a next generation regional commercial aircraft in Korea, are performed. Both the vortex theory and the blade element theory are used for preliminary aerodynamic design and performance analysis of the propeller. Then the aerodynamic design result is confirmed through performance analysis using a commercial CFD code, ANSYS. The carbon/epoxy composite materials is used, and the skin-spar-foam sandwich type structure is adopted for improvement of lightness and structural stability. Finally, it is investigated that the proposed propeller blade has high efficiency and structural safety through both aerodynamic and structural analysis and experimental test of a prototype propeller blade.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.253-258
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• 2012

In this study, designs of the high efficiency composite propeller blade for a high speed turboprop aircraft, which will be used for a next generation regional commercial aircraft in Korea, are performed. Both the vortex theory and the blade element theory are used for preliminary aerodynamic design and performance analysis of the propeller. Then the aerodynamic design result is confirmed through performance analysis using a commercial CFD code, ANSYS. The carbon/epoxy composite materials is used, and the skin-spar-foam sandwich type structure is adopted for improvement of lightness and structural stability. Finally, it is investigated that the proposed propeller blade has high efficiency and structural safety through both aerodynamic and structural analysis and experimental test of a prototype propeller blade.

• Composites Research
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• v.31 no.3
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• pp.104-110
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• 2018

This study is to propose the structural design and analysis procedure about composite blade and tower of vertical axis wind turbine technology. In this study, structural design of tower for vertical axis wind turbine was performed after vertical blade design and manufacturing. The structural design requirement and specification of blade and tower was investigated. After tower of structural design, the structural analysis of the tower was conducted by the finite element method. It was performed that the stress, deformation and natural frequency analysis at the applied loading. The design modification of tower configuration was proposed by structural analysis. It was confirmed that the final designed tower structure is safety through the structural analysis.

• Composites Research
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• v.35 no.1
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• pp.31-37
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• 2022

In this study, an optimal structural design framework has been developed for the structural design of composite helicopter blades. The optimal design framework is constructed using PSGA (Particle Swarm assisted Genetic Algorithm), which combines the genetic algorithm and particle swarm optimizer. The optimization process consists of a finite element (FE) modeling over the blade section, two-dimensional (2D) cross-sectional FE analysis, and 1D rotating blade analysis. In the design process, the geometric curves and surfaces are formed using the B-spline scheme while discretizing the sections via a FE mesh generation program Gmsh. The blade cross-sections are created in accordance with the design variables when performing the blade structural analysis. The proposed optimization design framework is applied to a modernization of the HART II (Higher-harmonic Aeroacoustics Rotor Test II) blades. It is demonstrated that an improved blade design is reached through the current optimization framework with the satisfaction of all design requirements set for the study.

• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.11-19
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• 2011

A localization development of Composite rotor blade for Smart Unmanned Aerial Vehicle(SUAV) has been conducted. Overall localization development encompassed selection of domestic composite material having similar properties to that of original one at its best, coupon tests for data base of new material properties, re-calculation of blade sectional properties, and validation of structural/dynamic design requirements such as isolation of rotor natural frequency from excitation, static and fatigue strength, aeroelastic stability. The results of all these activities are described. This paper briefly discusses the improved manufacturing process for the localization of SUAV blade.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.2
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• pp.95-101
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• 2020

The wind turbine blades should be designed to possess a high stiffness and should be fabricated with a light and high strength material because they serve under extreme combination of lift and drag forces, converting kinetic energy of wind into shaft work. The goal of this study is to understand the basic knowledge required to curtail the process time consumed during the construction of small wind turbine blades using carbon fiber reinforced polymer (CFRP) prepeg composites. The configuration of turbine rotor was determined using the QBlade freeware program. The fluid dynamics module simulated the loads exerted by the wind of a specific speed, and the stress analysis module predicted the distributions of equivalent von Mises stress for representing the blade structures. It was suggested to modify the shape of test specimen from ASTM D638 to decrease the variance in measured tensile strengths. Then, a series of experiments were performed to confirm that the bladder compression molded CFRP prepreg can provide sufficient strength to small wind turbine blades and decrease the cure time simultaneously.

• Transactions of the KSME C: Technology and Education
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• v.4 no.2
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• pp.93-99
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• 2016

High pressure nozzles and turbines of a gas turbine engine should be required to be operated under extreme operating conditions in order to maximize the performance. Engine manufactures have utilized nickel-base superalloys, enhanced cooling design, and thermal barrier coating techniques to overcome them and furthermore, material modeling, finite element analysis, optimization techniques, and etc. have been utilized widely for elaborate predictions. We aim to evaluate the effects on the low cycle fatigue life of the high pressure turbine blade caused by thermal barrier coatings and the cooling design of the endwall of the first stage turbine nozzle. To achieve it, the structural analysis, which utilized the results of conjugate heat transfer analysis as loading boundary conditions, was performed and then the results were the input for the assessment of low cycle fatigue life at several critical zones.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.185-191
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• 2008

The aerodynamic losses so attributed to the endwall - usually termed secondary flow losses or secondary losses - can be as high as 30$\sim$50% of the total aerodynamic losses in a blade or stator row. Inlet guide vanes, with lower total turning and higher convergence ratios, will have smaller secondary losses, amounting to as much as 20% of total loss for an inlet stator row. These are important part for improving a turbine efficiency. The present study deals with a leading edge chamfer groove on a wing-body to investigate the vortex generation and characteristics of a horseshoe vortex with the installed height, and depth of the groove. The current study is investigated with $FLUENT^{TM}$.