• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2262-2275
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• 2022

The Korea Atomic Energy Research Institute (KAERI) studied the sodium-water reaction (SWR) minimized steam generator for the safety of the sodium-cooled fast reactor (SFR), and selected the copper bonded steam generator (CBSG) as the optimal concept. This paper introduces the conceptual design of the CBSG and the development of the CBSG sizing analyzer (CBSGSA). The CBSG consists of multiple heat transfer modules with a crossflow heat transfer configuration where sodium flows horizontally and water flows vertically. The heat transfer modules are stacked along a vertical direction to achieve the targeted large heat transfer capacity. The CBSGSA code was developed for the thermal-hydraulic analysis of the CBSG in a multi-pass crossflow heat transfer configuration. Finally, we conducted a preliminary sizing and rating analysis of the CBSG for the trans-uranium (TRU) core system using the CBSGSA code proposed by KAERI.

• 한국전산유체공학회지
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• 제12권3호
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• pp.62-68
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• 2007

A conceptual thermal design is performed for the optical payload system of a geostationary satellite. The optical payload considered in this paper is GOCI(Geostationary Ocean Color Imager) of COMS of Korea. The radiative thermal control system is employed in order to expect a small thermal gradient in the telescope structure of GOCl. Two design margins are applied to the dedicated radiator dimensioning, and three kinds of configuration to the heater power sizing. A Monte-Carlo ray tracing method and a network analysis method are utilized to calculate radiative couplings and thermal responses respectively. At the level of conceptual design, sizing thresholds are presented for the radiator and heater on the purpose of determining the mass and power budget of the spacecraft.

• 한국항공운항학회지
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• 제18권3호
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• pp.1-8
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• 2010

A design study has been performed to obtain configuration and weight of a compound gyroplane. A study of research trends and characteristics was performed to develop the compound gyroplane sizing program. Based on these results, the sizing program has been developed and its suitability has been validated using existing compound gyroplane data. The subject air vehicles was a Challis Heliplane UAV, Carter Coptet, FB-1 Gyrodyne, and Jet Gyrodyne. As results, the program was suitable to size a compound gyroplane at conceptual design phase, because the greatest error rate was less than 10% and the conceptual design allowance error rate is less than 15%.

• 한국산학기술학회논문지
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• 제2권1호
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• pp.13-17
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• 2001

본 논문에서는 공업용 재봉기의 구성설계를 기능적 접근법을 이용하여 수행하였다. 구성설계 방법을 설계에 이용하면 제품의 개발시간을 줄일 수 있고, 기존의 기구 메커니즘 데이터를 효율적으로 이용할 수 있는데 이러한 구성설계를 구현하기 위해 전문가 시스템을 이용 하였다. 설계 구속조건은 전문가 시스템의 추론기능과 CBR(Case Based Reasoning) 방법을 사용하여 만족되도록 하였으며 전문가 시스템의 API 기능을 이용하여 기구해석과 최적설계가 외부 프로그램을 이용하여 수행됨으로서, 공업용 재봉기의 개념설계가 효율적으로 수행될 수 있도록 하였다.

• 한국항공우주학회지
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• 제41권5호
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• pp.404-414
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• 2013

전투기의 개념설계 과정에서는 기준형상 도출을 위해 비교분석연구가 반복된다. 반복적인 비교분석연구가 자동화되면 효율적으로 기준형상을 도출할 수 있다. 본 연구에서는 비교분석연구의 자동화를 위한 성능해석 프로그램을 개발했다. 프로그램은 형상생성모듈과 중량예측모듈, 임무성능 해석모듈로 구성된다. 형상생성모듈을 사용하여 3D CAD 모델 생성이 가능하며 중량예측모듈에서는 경험식을 사용하여 중량을 예측한다. 임의의 임무형상에 대한 임무성능 해석이 가능하며 최적화 기법을 사용하여 최적 임무성능 계산이 가능하다. 개발된 프로그램의 검증을 진행하여 개념설계 단계에 적용 가능함을 확인했다.

• 한국항공우주학회지
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• 제38권5호
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• pp.467-476
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• 2010

본 연구에서는 개념 설계 과정에서 항공 인증 규정 및 의사결정모델을 이용하여 최적화 문제 구성과 항공기 기준형상을 선정하는 프로세스를 정립하고, 이를 소형제트항공기에 적용하였다. 항공기 안전성을 보장하기 위한 최소안전 요구조건인 항공 인증 규정은 항공기 설계 초기단계에서부터 고려되어야 하는 사항으로 반드시 만족해야 한다. 인증 규정 및 사용자 요구도 분석 후, 산업공학기법인 Affinity Diagram, Nested Column Diagram, Quality Function Deployment (QFD), Pugh Concept Selection Matrix와 같은 의사결정모델을 사용하여 alternative 형상군에 대한 평가를 수행하였다. 그 후 Best alternative 형상에 대한 설계가능영역 분석을 통해 항공 인증 규정에 적합하고 객관적인 문제 구성 및 항공기 기준형상을 도출 할 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.172-180
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• 1999

The major subject of this paper is to develop the concept fur a Korea high speed train system and recommend to train configuration. High speed train configurations are basically concerned traction power(train configurations with concentrated; CPT or distributed Power system: DPT) and train design(single car as compared with articulated bogies). The result of configuration, a advantages and disadvantaged were necessitated by different train configurations; -distributed underfloor power have an increased length for the seats by 15% as compared with the concentrated power trait - articulated trainsets are characterised by less of number of bogies and reduced values of mass, train resistance, noise and vibration. from the result, the optimized train concept combining high seat capacity per train length with low weight and train resistance is 400m long, single -floor train composed of two symmetrically arranged half trainsets. Therefore, at this work recommended distributed train system However, the final decision of Korea high speed train configuration was concentrated power train and articulated bogie system. The configuration of trainset was 20cars included 2 power cars, 4 motorized cars and 14 trailer cars.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.97-104
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• 2006

The geometric configuration in the weight reduction designis very required to be started from the conceptual design with low cost, high performance and quality. In this point, a structural-topological shape concerned with conceptual design of structure is important. The method used in this paper combines three optimization techniques, where the shape and physical dimensions of the structure and material distribution are hierachically optimized, with the maximum rigidity of structure and lightweight. As the results, the technology of weight reduction design is considered in designs of aluminum control arm and inner panel of door.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.173-178
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• 2011

Nowadays, SELENE-2 is under development for the moon explorer rover in Japan. AXS(Active X-ray Spectrometer) sensor development among the candidated payloads will be on going by the world-wide co-operation. The thermal design, analysis and test will be specially performed by Korean institutes. CFD techniques are used for the conceptual design and analysis. Thin-shell plate meshes being applied by Monte-Carlo Ray Tracing Method are generated for the thermal radiation analysis. Lumped capacity model is employed for the thermal conduction simulation of the AXS payload itself. Various shapes of the payload configuration with thermal boundary conditions are proposed and selected on the purpose of the analysis of the initial design. The results of the analysis are supposed to be used as the baseline for the further detailed design of the AXS payload in the future.

• 한국정밀공학회지
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• 제13권7호
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• pp.66-77
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• 1996

Optimal topology design is to search the optimal configuration of a structure which can be used as a shape at the conceptual design stage. Our objective is to maximize the stiffness of the structures and ribs under a material usage constraintl. The density of each finite element is the design variable and its relationship with Young's modulus is expressed by quadratic form. The configuration is represented by the entire density distribution, the structural analysis is performed by finite element method and the optimiza- tion is performed by Feasible Direction Method. Feasible Direction Method can handle various problems simultaneously, that is, mult-objectives and multi-constraints. Total computation time can be reduced by the quadratic relationship between the density and the material property and fewer design variables than Homogenization Method. Toplogy optimization technique developed in this research is applied to design the shapes of the ribs.