• 제목/요약/키워드: CFD

검색결과 5,741건 처리시간 0.031초

고온 고압 환경에서 가변추력기용 핀틀의 열전달 계수에 대한 수치적 연구 및 2D 실험 (Numerical Analysis and 2-D Experiment of Heat Transfer Coefficient on the Pintle of a Controllable Thruster Nozzle)

  • 박순상;문영기;곽재수
    • 항공우주시스템공학회지
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    • 제6권4호
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    • pp.24-28
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    • 2012
  • In this paper, 2-D experiment and steady-state computational fluid analysis were conducted for measuring the hear transfer coefficient of pintle type controllable thruster in high pressure and temperature. In case of 2-D experiment, transient liquid crystal technique was used for measuring heat transfer coefficient for the 2-D pintle model. The experimental result was used to validate the CFD result. The CFD results well predicted the heat transfer coefficient on the pintle surface except the nozzle downstream region, where the results by CFD was higher than experimental results. The CFD results were also compared with the result by Bartz equation and the it was shown that the Bartz equation overestimated the heat transfer coefficient on the nozzle throat as much as 80%.

소형 챔버법에 의한 건축자재의 휘발성유기화합물 방출량 측정 및 CFD해석 (Validating of small chamber method by CFD simulation and VOCs emission rate of construction materials.)

  • 김윤덕
    • 한국태양에너지학회 논문집
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    • 제26권3호
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    • pp.99-110
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    • 2006
  • This study focused on the emission rate of the construction materials. The method of study is as follows. First, validation of small chamber method to determine emission rate of construction material was performed by CFD simulation. For the result of this study, uniform air velocity in small chamber was founded, and small chamber as a test material for emission rate was validated. Second, the construction materials were categorized by their feature and the emission rate of volatile organic compound was determined. Totally, VOCs emission rate of 49 materials were determined.

비틀림각에 따른 HWAT의 공력특성 전산해석 (CFD ANALYSIS OF AERODYNAMIC CHARACTERISTICS OF HWAT BASED ON THE DIFFERENT TWIST ANGLE USING CFD)

  • 이명수;유성수;황도연;한병윤;박형구
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2009년 추계학술대회논문집
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    • pp.19-26
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    • 2009
  • The objective of this study is to investigate aerodynamic characteristics of a Horizontal-axis wind turbines(HAWT), using CFD method with a commercial code STAR-CCM+ version 3.06. To verify the reliability of the computations, the CFD results are compared with the experimental ones of the National Renewable Energy Laboratory(NREL) Phase Ⅵ HAWT. For the comparison and examination of aerodynamic characteristics, the existent shape with a predesigned twist angle was replaced by the one with one-dimensional linear twist angle. In this study, the pressure contour and stream line around the blade were analyzed as main focus. Through this study the more efficient shape of airfoil is suggested with consideration of manufacturing cost.

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맥동류 내 물체 형상에 따른 항력에 대한 CFD 계산 (CFD ANALYSIS FOR THE DRAG OF AN INTERIOR BODY IN A PULSATILE FLOW WITH VARIOUS SHAPE DESIGN)

  • 황도연;한병윤;유성수;이명수;박형구
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2009년 추계학술대회논문집
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    • pp.38-43
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    • 2009
  • The objective of this study is to get a fundamental data for the shape of a robot which operates in blood vessels. The overall analysis was calculated with a CFD code. The flow was idealized as a pulsatile flow, and first the robot was assumed as a simple capsule model. Then a drag of the body in the flow was calculated, and this process was repeated, varying the shape. To validate all the result, the pulastile velocity simulation was compared with the theoretical data, and the drag of a body was compared with the existing data of the other papers first. Then with the next calculation the guideline for the design of robot shape was presented.

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CFD를 이용한 컨테이너선의 Post Swirl Stator 설계기법 (Design Technique of Post Swirl Stator in Container Vessels by CFD)

  • 김기현;송인행;최순호
    • 대한조선학회논문집
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    • 제44권2호
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    • pp.93-100
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    • 2007
  • Post swirl stator is an energy saving device to recover rotational energy of the propeller. To optimize the performance of post swirl stator in container vessels, computational fluid dynamics using body force method was introduced. A commercial code Fluent was used in conjunction with body force distributed on the surface of actuator disk which is located in the propeller plane to optimize pitch angle of the post swirl stator blade. This study showed that CFD is an important tool to simulate flow behind ship with propeller, rudder and post swirl stator.

TeraCluster에서 CFD 코드의 병렬 성능 분석 (Performance Analysis of a CFD code in the TeraCluster Parallel System)

  • 조금원;이상산
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2000년도 추계 학술대회논문집
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    • pp.92-100
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    • 2000
  • At the end of 1999. the TeraCluster project has started in the KORDIC Supercomputer center to study PC clusters for parallel computing. The aim is to replace the Cray T3E with a new cluster system in 2002. The PC cluster without a fast network is well suited for applications which do not require large amount of global communications. Since CFD problems are not very communication intensive, whole test cluster may be efficiently used. As an example of practical CFD simulations. the flow past the ONERA M6 wing and the flow past infinite wing are simulated on a cluster of Linux workstations.

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Including Thermal Effects in CFD Wind Flow Simulations

  • Meissner, Catherine;Gravdahl, Arne Reidar;Steensen, Birthe
    • 한국환경과학회지
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    • 제18권8호
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    • pp.833-839
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    • 2009
  • The calculation of the wind field for resource assessment is done by using CFD Reynolds-Averaged Navier-Stokes simulations performed with the commercial software WindSim. A new interface has been created to use mesoscale simulation data from a meteorological model as driving data for the simulations. This method makes it necessary to take into account thermal effects on the wind field to exploit the full potential of this method. The procedure for considering thermal effects in CFD wind field simulations as well as the impact of thermal effects on the wind field simulations is presented. Simulations for non-neutral atmospheric conditions with the developed method are consistent with expected behavior and show an improvement of simulation results compared with observations.

다양한 PC 클러스터 시스템 환경에서 CFD 코드의 성능 분석 (Performance Analysis of a CFD Code in Several PC Cluster Systems)

  • 조금원;홍정우;이상산
    • 한국전산유체공학회지
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    • 제6권2호
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    • pp.47-55
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    • 2001
  • In recent years cluster systems using off-the-shelf processors and networks components have been increasing popular. Since actual performance of a cluster system varies significantly for different architectures, representative in-house codes from major application fields were executed to evaluate the actual performance of systems with different combination of CPU, network, and network topology. As an example of practical CFD(Computational Fluid Dynamics) simulations, the flow past an Onera-M6 wing and the flow past an infinite wing were simulated on clusters of Linux and several other hardware environments.

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비정렬 셀 중심방법 및 경계면포착법을 사용하는 3차원 유동해석코드(PowerCFD)에 적합한 HR 해법에 관한 연구 (STUDY ON HIGH RESOLUTION SCHEMES SUITABLE FOR AN 3-D CFD CODE(POWERCFD) USING UNSTRUCTURED CELL-CENTERED METHOD AND INTERFACE CAPTURING METHOD)

  • 명현국;김종은
    • 한국전산유체공학회지
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    • 제13권1호
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    • pp.7-13
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    • 2008
  • Several high resolution schemes such as OSHER, MUSCL, SMART, GAMMA, WACEB and CUBISTA are comparatively studied with respect to the accurate capturing of fluid interfaces throughout the application to two typical test cases of a translation test and a collapsing water column problem with a return wave. It is accomplished by implementing the high resolution schemes in the in-house CFD code(PowerCFD) for computing 3-D flow with an unstructured cell-centered method and an interface capturing method, which is based on the finite-volume technique and fully conservative. The calculated results show that SMART scheme gives the best performance with respect to accuracy and robustness.

CFD - Mature Technology?

  • Kwak, Do-Chan
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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    • pp.257-261
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    • 2005
  • Over the past 30 years, numerical methods and simulation tools for fluid dynamic problems have advanced as a new discipline, namely, computational fluid dynamics (CFD). Although a wide spectrum of flow regimes are encountered in many areas of science and engineering, simulation of compressible flow has been the major driver for developing computational algorithms and tools. This Is probably due to a large demand for predicting the aerodynamic performance characteristics of flight vehicles, such as commercial, military, and space vehicles. As flow analysis is required to be more accurate and computationally efficient for both commercial and mission-oriented applications (such as those encountered in meteorology, aerospace vehicle development, general fluid engineering and biofluid analysis) CFD tools for engineering become increasingly important for predicting safety, performance and cost. This paper presents the author's perspective on the maturity of CFD, especially from an aerospace engineering point of view.

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