• 제목/요약/키워드: Aerodynamic Optimization

검색결과 224건 처리시간 0.029초

A Design Optimization Study of Diffuser Shape in a Supersonic Inlet

  • Lim, S.;Koh, D.H.;Kim, S.D.;Song, D.J.
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.756-760
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    • 2008
  • Optimum shape of Double-cone supersonic inlet is studied by using numerical methods. Double-cone intake shape is used for the design optimization study. And the total pressure recovery at the exit is used to assess the aerodynamic performance of the inlet.

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민감도 해석을 이용한 동적실속 제어 (Dynamic Stall Control Using Aerodynamic Sensitivity Analysis)

  • 안태술;김형진;김종암;노오현
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2000년도 추계 학술대회논문집
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    • pp.176-182
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    • 2000
  • This paper presents methods for dynamic stall control utilizing an optimization approach. Unsteady aerodynamic sensitivity code is developed using a direct diffentiation method from a discrete two-dimensional unsteady compressible Navier-Stokes code including a two-equation turbulence model. Dynamic stall control is conducted by minimizing an objective function defined at an instant instead of integrating a response for a period of time. Unsteady sensitivity derivative of the objective function is calculated by the sensitivity code, and optimization is conducted using a linear line search method at every physical time level. Examples of dynamic stall control utilizing airfoils nose radius or maximum thickness variation show very satisfactory results.

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항공기 형상 최적설계 프로세스를 위한 표면 격자 자동 생성 프로그램의 개발 (DEVELOPMENT OF AUTOMATIC PANEL GENERATION PROGRAM FOR AIRCRAFT SHAPE OPTIMIZATION PROCESS)

  • 김경남;김병수
    • 한국전산유체공학회지
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    • 제20권3호
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    • pp.41-46
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    • 2015
  • This paper describes study results on the development of an automatic program for generating surface-panel grid for the aircraft optimal design. The aerodynamic analysis is combined into a PIDO tool in conjunction with a number of programs in order to integrate processes for the optimal design. Due to design optimization's iterative feature, it may require lots of time and cost. To relieve this problem, cost-reduction of computation time for aerodynamic analysis is pursued by using the Panel-method, and reduction of grid generation time by automating surface panelling.

스마트 무인기 날개용 에어포일의 공력최적설계 (Aerodynamic Design Optimization of Smart UAV Wing Airfoil)

  • 박영민;정진덕;김유신;최성욱
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2004년도 추계 학술대회논문집
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    • pp.193-196
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    • 2004
  • Numerical optimization method of long endurance airfoil has been performed with a RSM(Response Surface Method) for smart UAV wing design. For the base line airfoil, NACA 64621 airfoil was selected and optimized to satisfy long endurance condition for smart UAV Aerodynamic coefficients required for RSM are obtained by using 2-D Navier-Stokes solver with Spalart-Allmaras turbulence model. The optimized airfoil showed increased maximum lift and endurance factors together with reasonable thickness ratio.

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유전자 알고리즘을 사용한 공기역학적 Airfoil 형상 최적화 (A Study on Optimal Aerodynamic Shape of Airfoil using a Genetic Algorithm)

  • 정성기;도옹안호앙;이영민;제소영;명노신;조태환
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.377-380
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    • 2008
  • In this study, an aerodynamic shape optimization system was developed to study the optimal shape of airfoil. The system consists of GA (Genetic Algorithm) and CFD code based on the Navier-Stokes equation. Lift-drag ratio is chosen as the object function and optimization is conducted for PARSEC airfoil with nine design variables, which is very efficient in representing the surface geometry of airfoil.

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목적 공력특성 달성을 위한 플루트 노즐 전산설계 (COMPUTATIONAL DESIGN OF A FLUTED NOZZLE FOR ACHIEVING TARGET AERODYNAMIC PERFORMANCE)

  • 강영진;양영록;황의창;명노신;조태환
    • 한국전산유체공학회지
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    • 제16권3호
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    • pp.1-7
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    • 2011
  • As a preliminary design study to achieve target aerodynamic performance, this work was conducted on an original nozzle with 9 flutes in order to design a fluted nozzle with 12 flutes. The thrust and rolling moment of the nozzle with 12 flutes were analyzed using a CFD code according to the depth and rotation angle of the flutes. Based on this, a fluted nozzle with 12 flutes was optimized to yield the same thrust as that of the original nozzle with 9 flutes. The response surface method was applied for shape optimization of the fluted nozzle and design variables were selected to determine the depth angle and rotation angle of the flutes. An optimized shape that led to a thrust as strong as that of the original nozzle was obtained.

근사모델을 이용한 날개 평면형상 공력형상설계 방법 (Aerodynamic Shape Design Method for Wing Planform Using Metamodel)

  • 배효길;정소라
    • 항공우주시스템공학회지
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    • 제8권4호
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    • pp.18-23
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    • 2014
  • In preliminary design phase, the wing geometry of the civil aircraft was determined using the empirical equation and historical data. To make wing geometry more aerodynamically efficient, an aerodynamic shape optimization was conducted. For this purpose the parametric modeling, high fidelity CFD analysis and metamodel-based optimal design technique were adopted. The parametric modeling got the design process to achieve the improvement by generating the configuration outputs easily for the major design variables. The optimal design equations were formularized as the type of the multi-objective functions considering low/high speed and lift/drag coefficient. The optimal solution was explored with the help of the kriging metamodel and the desirability function, therefore the optimal wing planform was sought to be excellent at both low and high speed region. Additionally the optimal wing planform was validated that it was excellent not only at the specific AOA, but also all over the range of AOA.

전산유체역학을 이용한 수치 최적설계 (Numerical optimization design by computational fluid dynamics)

  • 이정우;문영준
    • 대한기계학회논문집B
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    • 제20권7호
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    • pp.2347-2355
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    • 1996
  • Purpose of the present study is to develop a computational design program for shape optimization, combining the numerical optimization technique with the flow analysis code. The present methodology is then validated in three cases of aerodynamic shape optimization. In the numerical optimization, a feasible direction optimization algorithm and shape functions are considered. In the flow analysis, the Navier-Stokes equations are discretized by a cell-centered finite volume method, and Roe's flux difference splitting TVD scheme and ADI method are used. The developed design code is applied to a transonic channel flow over a bump, and an external flow over a NACA0012 airfoil to minimize the wave drag induced by shock waves. Also a separated subsonic flow over a NACA0024 airfoil is considered to determine a maximum allowable thickness of the airfoil without separation.

덮개꼬리로부터의 형상변화에 따른 공력 특성에 관한 연구 (Effect of Geometric Variation on Aerodynamic Characteristics of a Shrouded Tail Rotor)

  • 이희동;강희정;권오준
    • 한국항공우주학회지
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    • 제33권5호
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    • pp.9-17
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    • 2005
  • 헬리콥터 초기 설계 단계에서는 형상 변화에 따른 공력 성능 변화를 예측하여 최적의 형상을 결정한다. 덮개꼬리로터에서는 공력성능 개선을 위해 블레이드와 덮개사이의 끝단간극, 블레이드 평면형, 그리고 블레이드 배치의 최적화가 필요하다. 본 연구에서는 비정렬 격자에 기초한 비점성 압축성 로터 유동 해석 코드를 이용하여 설계 초기 기본형상의 덮개꼬리로터에 대해 끝단간극, 블레이드 평면형, 그리고 블레이드 배치 등의 형상변화에 따른 공력 성능을 예측하고 그 특성을 파악하였다.

1MW급 풍력 터빈 블레이드의 허브 및 드라이브 트레인 공력 하중 해석 (Aerodynamic Load Analysis at Hub and Drive Train for 1MW HAWT Blade)

  • 조봉현;이창수;최성옥;유기완
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.25-32
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    • 2005
  • The aerodynamic loads at the blade hub and the drive shaft for 1MW horizontal axis wind turbine are calculated numerically. The geometric shape of the blade such as chord length and twist angle can be obtained fran the aerodynamic optimization procedure. Various airfoil data, that is thick airfoils at hub side and thin airfoils at tip side, are distributed along the spanwise direction of the rotor blade. Under the wind data fulfilling design load cases based on the IEC61400-1, all of the shear forces, bending moments at the hub and the low speed shaft of the drive train are obtained by using the FAST code. It shows that shear forces and bending moments have a periodic. trend. These oscillating aerodynamic loads will lead to the fatigue problem at both of the hub and drive train From the load analysis the maximum shear forces and bending moments are generated when wind turbine generator system operates in the case of the extreme speed wind condition.

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