Coupled Analysis of Thermo-Fluid-Flexible Multi-body Dynamics of a Two-Dimensional Engine Nozzle

WonJong Eun,JaeWon Kim,Oh-Joon Kwon,Chanhoon Chung,Sang-Joon Shin,Olivier A. Bauchau 한국항공우주학회 2017 International Journal of Aeronautical and Space Sc Vol.18 No.1

Various components of an engine nozzle are modeled as flexible multi-body components that are operated under high temperature and pressure. In this paper, in order to predict complex behavior of an engine nozzle, thermo-fluid-flexible multibody dynamics coupled analysis framework was developed. Temperature and pressure on the nozzle wall were obtained by the steady-state flow analysis for a two-dimensional nozzle. The pressure and temperature-dependent material properties were delivered to the flexible multi-body dynamics analysis. Then the deflection and strain distribution for a nozzle configuration was obtained. Heat conduction and thermal analyses were done using MSC.NASTRAN. The present framework was validated for a simple nozzle configuration by using a one-way coupled analysis. A two-way coupled analysis was also performed for the simple nozzle with an arbitrary joint clearance, and an asymmetric flow was observed. Finally, the total strain result for a realistic nozzle configuration was obtained using the one-way and two-way coupled analyses.

지적구조 규명을 위한 키워드서지결합분석 기법에 관한 연구

이재윤,정은경 한국정보관리학회 2022 정보관리학회지 Vol.39 No.1

Intellectual structure analysis, which quantitatively identifies the structure, characteristics, and sub-domains of fields, has rapidly increased in recent years. Analysis techniques traditionally used to conduct intellectual structure analysis research include bibliographic coupling analysis, co-citation analysis, co-occurrence analysis, and author bibliographic coupling analysis. This study proposes a novel intellectual structure analysis method, Keyword Bibliographic Coupling Analysis (KBCA). The Keyword Bibliographic Coupling Analysis (KBCA) is a variation of the author bibliographic coupling analysis, which targets keywords instead of authors. It calculates the number of references shared by two keywords to the degree of coupling between the two keywords. A set of 1,366 articles in the field of ‘Open Data’ searched in the Web of Science were collected using the proposed KBCA technique. A total of 63 keywords that appeared more than 7 times, extracted from 1,366 article sets, were selected as core keywords in the open data field. The intellectual structure presented by the KBCA technique with 63 key keywords identified the main areas of open government and open science and 10 sub-areas. On the other hand, the intellectual structure network of co-occurrence word analysis was found to be insufficient in the overall structure and detailed domain structure. This result can be considered because the KBCA sufficiently measures the relationship between keywords using the degree of bibliographic coupling. 학문의 구조, 특성, 하위 분야 등을 계량적으로 규명하는 지적구조 분석 연구가 최근 급격히 증가하는 추세이다. 지적구조 분석 연구를 수행하기 위하여 전통적으로 사용되는 분석기법은 서지결합분석, 동시인용분석, 단어동시출현분석, 저자서지결합분석 등이다. 이 연구의 목적은 키워드서지결합분석(KBCA, Keyword Bibliographic Coupling Analysis)을 새로운 지적구조 분석 방식으로 제안하고자 한다. 키워드서지결합분석 기법은 저자서지결합분석의 변형으로 저자 대신에 키워드를 표지로 하여 키워드가 공유한 참고문헌의 수를 두 키워드의 주제적 결합 정도로 산정한다. 제안된 키워드서지결합분석 기법을 사용하여 Web of Science에서 검색된 ‘Open Data’ 분야의 1,366건의 논문집합을 대상으로 분석하였다. 1,366건의 논문집합에서 추출된 7회 이상 출현한 63종의 키워드를 오픈데이터 분야의 핵심 키워드로 선정하였다. 63종의 핵심 키워드를 대상으로 키워드서지결합분석 기법으로 제시된 지적구조는 열린정부와 오픈사이언스라는 주된 영역과 10개의 소주제로 규명되었다. 이에 반해 단어동시출현분석의 지적구조 네트워크는 전체 구성과 세부 영역 구조 규명에 있어 미진한 것으로 나타났다. 이러한 결과는 키워드서지결합분석이 키워드 간의 서지결합도를 사용하여 키워드 간의 관계를 풍부하게 측정하기 때문이라고 볼 수 있다.

Analysis on Harmonic Loss of IPMSM for the Variable DC-link Voltage through the FEM-Control Coupled Analysis

Hyun Soo Park,Tae Chul Jeung,Jae Kwang Lee,Byoung Kuk Lee 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

This paper describes the loss analysis based on load conditions of the air conditioning compressor motors using variable dc-link voltage. The losses of PMSM (Permanent Magnet Synchronous Motor) should be analyzed by the PWM (Pulse Width Modulation) output of inverter. The harmonic loss by the PWM cannot consider that using the current source analysis of the inverter. In addition, when the voltage of dc-link is variable with the condition of variable speed and load conditions in motor, the losses of motor are also changeable, however it is hard to analyze those losses by only electromagnetic finite element method (FEM). Therefore, this paper proposes the analysis method considering the carrier frequency of the inverter and the varying state of the dc-link voltage through the FEM-control coupled analysis. Using proposed analysis method, additional core loss and eddy current loss of permanent magnet caused by PWM could be analyzed. Finally, the validity of the proposed analysis method is verified through the comparison the result of coupled analysis with experiment.

Coupled Analysis of Thermo-Fluid-Flexible Multi-body Dynamics of a Two-Dimensional Engine Nozzle

Eun, WonJong,Kim, JaeWon,Kwon, Oh-Joon,Chung, Chanhoon,Shin, Sang-Joon,Bauchau, Olivier A. The Korean Society for Aeronautical and Space Scie 2017 International Journal of Aeronautical and Space Sc Vol.18 No.1

Various components of an engine nozzle are modeled as flexible multi-body components that are operated under high temperature and pressure. In this paper, in order to predict complex behavior of an engine nozzle, thermo-fluid-flexible multi-body dynamics coupled analysis framework was developed. Temperature and pressure on the nozzle wall were obtained by the steady-state flow analysis for a two-dimensional nozzle. The pressure and temperature-dependent material properties were delivered to the flexible multi-body dynamics analysis. Then the deflection and strain distribution for a nozzle configuration was obtained. Heat conduction and thermal analyses were done using MSC.NASTRAN. The present framework was validated for a simple nozzle configuration by using a one-way coupled analysis. A two-way coupled analysis was also performed for the simple nozzle with an arbitrary joint clearance, and an asymmetric flow was observed. Finally, the total strain result for a realistic nozzle configuration was obtained using the one-way and two-way coupled analyses.

Electromagnetic Forming Process Analysis Based on Coupled Simulations of Electromagnetic Analysis and Structural Analysis

Man Gi Lee,Seung Hwan Lee,Sunwoo Kim,Jin Ho Kim 한국자기학회 2016 Journal of Magnetics Vol.21 No.2

We conducted a phased electromagnetic forming process analysis (EFPA) over time through a coupling of electromagnetic analysis and structural analysis. The analysis is conducted through a direct linkage between electromagnetic analysis and structural analysis. The analysis process is repeated until the electric current is completely discharged by a formed coil. We calculate the forming force that affects the workpiece using MAXWELL, a commercial electromagnetic finite element analysis program. Then, we simulate plastic behavior by using the calculated forming force data as the forming force input to ANSYS, a commercial structure finite element analysis program. We calculate the forming force data by using the model shape in MAXWELL, a commercial electromagnetic finite element analysis program. We repeat the process until the current is fully discharged by the formed coil. Our results can be used to reduce the error in data transformation with a reduced number of data transformations, because the proposed approach directly links the electromagnetic analysis and the structural analysis after removing the step of the numerical analysis of a graph describing the forming force, unlike the existing electromagnetic forming process. Second, it is possible to simulate a more realistic forming force by keeping a certain distance between nodes using the re-mesh function during the repeated analysis until the current is completely discharged by the formed coil, based on the MAXWELL results. We compare and review the results of the EFPA using the peak value of the forming force that acts on the workpiece (which is the existing analysis method), and the proposed phased EFPA over time approach.

Vibration analysis of electric motors considering rotating rotor structure using flexible multibody dynamics-electromagnetic-structural vibration coupled analysis

Cho Seunghyeon,전경훈,김창완 한국CDE학회 2023 Journal of computational design and engineering Vol.10 No.2

In this study, we develop flexible multibody dynamic-electromagnetic-structural vibration coupled analysis method to accurately predict motor vibration by considering the electromagnetic force characteristics, rotating characteristics of rotating motor motors, and their interactions at the no-load rated speed and operating speed range. The structural characteristics are accurately reflected by developing a three-dimensional (3D) finite element model considering the entire components of the motor. The reliability of the 3D finite element model of the motor is verified using the impact hammer test. In addition, to consider the rotational characteristics of the rotor structure, we develop a flexible multibody dynamics model that connects the flexible rotor and the bearing with revolute joint. The vibration of the motor at the no-load rated speed is analyzed using flexible multibody dynamics-electromagnetic-structural vibration coupled analysis. Comparing the vibration test results, it is confirmed that the flexible multibody dynamics-electromagnetic-structural vibration coupled analysis result predicts the actual motor vibration more accurately than the conventional finite element analysis-based electromagnetic-structural vibration coupled analysis result. By using flexible multibody dynamics-electromagnetic-structural vibration coupled analysis in the operating speed range, it is confirmed that not only electromagnetic force harmonics but also sideband harmonics caused by rotor eccentricity-induced large vibrations, and also confirmed that it accurately predicts the vibration characteristics of actual motors with rotating rotors.

자동차 플라스틱 제품의 Glass Fiber 배향성이 강성에 미치는 영향

김웅(Woong Kim),김종량(Jong Ryang Kim) 한국자동차공학회 2016 한국자동차공학회 학술대회 및 전시회 Vol.2016 No.11

With the purpose of improving the strength and light weight, the using of engineering plastic about automotive parts is rising. It is necessary to apply the engineering plastic for the cost down, the production efficiency and light weight. To produce the automotive parts, prior design, prediction of defeat and validation of injection molding are important. From this reason, the injection molding analysis, structural analysis are applied to develop products. Especially the injection molding analysis has highly complicated mechanism to consider polymer properties and is essential for the different analysis approaching for the orthotropic material properties differ from general steel with isotropic material properties. Since the parts from polymer have the deformation, residual stress after injection molding such as pre-stress. That is the most important fact that the different from the general structural analysis with isotropic material properties. In addition, It is sure that the results of analysis with isotropic & orthotropic material properties. The strength of polymer parts is consisted of mass production, application, producing affect at injection molding conditions, cavity design, molding design. Glass fiber orientation is the serious causes to make a problem that strength is down in spite of the best injection molding conditions & cavity design. The application of injection molding - structural coupling analysis is useful that the validation of product and injection molding analysis. The Purpose of thesis is that the validation, pre-study, solution of defeat about polymer automotive parts using injection molding – structural coupling analysis. PPS (Poly Phenylene Sulfide) containing glass fiber 40% to improve the strength is used. Also some of them to solve the problem such as simulation program make use of injection molding analysis, structural analysis and coupling analysis. Finally, it is able to suggest that the improving strength, design of plastic parts using by the injection molding – structural coupling analysis.

Analysis on Harmonic Loss of IPMSM for the Variable DC-link Voltage through the FEM-Control Coupled Analysis

Park, Hyun Soo,Jeung, Tae Chul,Lee, Jae Kwang,Lee, Byoung Kuk The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

This paper describes the loss analysis based on load conditions of the air conditioning compressor motors using variable dc-link voltage. The losses of PMSM (Permanent Magnet Synchronous Motor) should be analyzed by the PWM (Pulse Width Modulation) output of inverter. The harmonic loss by the PWM cannot consider that using the current source analysis of the inverter. In addition, when the voltage of dc-link is variable with the condition of variable speed and load conditions in motor, the losses of motor are also changeable, however it is hard to analyze those losses by only electromagnetic finite element method (FEM). Therefore, this paper proposes the analysis method considering the carrier frequency of the inverter and the varying state of the dc-link voltage through the FEM-control coupled analysis. Using proposed analysis method, additional core loss and eddy current loss of permanent magnet caused by PWM could be analyzed. Finally, the validity of the proposed analysis method is verified through the comparison the result of coupled analysis with experiment.

Analysis on Harmonic Loss of IPMSM for the Variable DC-link Voltage through the FEM-Control Coupled Analysis

박현수,정태철,이재광,이병국 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

This paper describes the loss analysis based on load conditions of the air conditioning compressor motors using variable dc-link voltage. The losses of PMSM (Permanent Magnet Synchronous Motor) should be analyzed by the PWM (Pulse Width Modulation) output of inverter. The harmonic loss by the PWM cannot consider that using the current source analysis of the inverter. In addition, when the voltage of dc-link is variable with the condition of variable speed and load conditions in motor, the losses of motor are also changeable, however it is hard to analyze those losses by only electromagnetic finite element method (FEM). Therefore, this paper proposes the analysis method considering the carrier frequency of the inverter and the varying state of the dc-link voltage through the FEM-control coupled analysis. Using proposed analysis method, additional core loss and eddy current loss of permanent magnet caused by PWM could be analyzed. Finally, the validity of the proposed analysis method is verified through the comparison the result of coupled analysis with experiment.

서지적 저자결합분석 - 연구동향 분석을 위한 새로운 접근 -

이재윤 한국정보관리학회 2008 정보관리학회지 Vol.25 No.1

Author co-citation analysis(ACA) technique has been widely used for identifying research areas and trends in a discipline. But this technique has some limitations, mainly due to citation delay, on analyzing current trends and identifying active researchers. In this study, a new method, named as Bibliographic Author Coupling Analysis(BACA), is suggested for overcoming those limitations of author co-citation analysis. BACA is based on Kessler's bibliographic coupling approach and focuses not on documents but on authors. Simply stated, BACA technique assumes that those likewise citing authors have the same research interests. For the purpose of comparing with author co-citation analysis, two preceding studies with author co-citation analysis are reconsidered and re-examined using BACA. The comparing results can be regarded as promising the usefulness of BACA in analyzing current research trends and identifying active researchers. 저자동시인용분석 기법은 특정 분야의 연구 주제와 동향을 파악하는 수단으로 널리 사용되어왔다. 그러나 저자동시인용분석 기법은 인용 지체 현상 때문에 최근 동향을 나타내거나 활동적인 현역 연구자를 파악하기에는 다소 한계가 있음이 알려져 있다. 이 연구에서는 최신 연구 동향을 분석함과 동시에 활동적인 연구자를 파악하기위한 새로운 방법으로 서지적 저자결합분석 기법을 제안한다. 이 기법은 Kessler가 제안한 서지결합에 기반을 두되 분석 단위를 문헌이 아닌 저자로 삼고 있다. 즉 서지적 저자결합분석 기법은 같은 저자를 인용하는 저자끼리는 연구 주제가 유사할 것이라는 가정에 근거한 분석 기법이다. 저자동시인용분석 기법을 사용한 기존 연구의 분석 결과를 서지적 저자결합분석을 적용한 경우와 비교해본 결과, 제안된 기법이 저자동시인용분석 기법에 비해서 최근 연구 동향을 더 잘 반영하며 활동적인 현역 연구자 위주의 해석을 가능케 하는 것으로 나타났다.