• 한국추진공학회지
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• 제24권3호
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• pp.71-80
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• 2020

발사체 분석을 위한 CFD 소프트웨어인 LVAFoam을 개발하기 앞서 발사체의 연소기, 터보 펌프 및 외부유동의 시뮬레이션에 사용된 해외의 인하우스 CFD 소프트웨어 및 상용 CFD 소프트웨어에 대한 조사를 수행하였다. 인하우스 소프트웨어로는 NASA, 미시시피 주립대학, DLR, Bertin Technologies & CNES, CERFACS 및 JAXA의 솔버들과, 상용 소프트웨어로는 FLUENT, CFX, Adavance/FrontFlow/red, GASP, CRUNCH CFD, CFD-ACE+, FINE^TM/Turbo, STAR-CCM+ 의 솔버들을 정리하였다. 발사체 분석을 위한 각 소프트웨어의 계산 사례가 제시되었으며, 개발된 LVAFoam이 간략하게 소개되었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.327-330
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• 2011

CFD simulation is widely used in various industries, universities and research centers. In Korea most of the researchers use foreign commercial S/W packages especially in industries. But commercial CFD packages have some problems as limit to source code and very high license foe. So from several years ago open source CFD code has been widely spread as an alternative. But in Korea there are a few users of open source code. Insufficiency of performance validation as for accuracy, robustness, convenience and parallel speed-up is important obstacles of open source code. So we tested some validation cases as to incompressible external aerodynamics and internal flaws and now are doing compressible flaws. As the first stage of compressible flow validation, we simulated Korea next generation high speed train(HEMU). It's running condition is 400km/hr and maximum Mach number reaches up to 0.4. With the high speed train we tested accuracy, robustness and parallel performance of open source CFD code OpenFOAM Because there isn't experimental data we compared results with widely used commercial code. When use $1^{st}$ order upwind scheme aerodynamic forces are very similar to commercial code. But using $2^{nd}$ order upwind scheme there was some discrepancy. The reason of the difference is not clear yet. Mesh manipulation, domain decomposition, post-processing and robustness are satisfactory. Paralle lperformance is similar to commercial code.

• 대한조선학회논문집
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• 제49권2호
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• pp.151-157
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• 2012

The present study explored the possibilities of the applications of open source libraries to shipbuilding and marine engineering industries. A computational fluid dynamics (CFD) code, termed SNUFOAM, was developed and tested for turbulent flow around a ship, free surface flow around a hull, cavitating flow, and vortex shedding dynamics around a cylinder. The results using the developed CFD codes were compared against existing experimental data and solution of commercial CFD codes. SNUFOAM showed the nearly same results as commercial CFD codes and proved to be an alternative to commercial CFD codes for shipbuilding and marine engineering industries.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.91-94
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• 2013

Commercial computational fluid dynamics (CFD) codes traditionally rely on the computational efficiency of the simplified single-film apparent char kinetic model to predict char particle temperatures and char conversion rates in pulverized coal boilers. The aim of this study is to evaluate the reliability of the single-film apparent kinetic model and to suggest the importance of proper use of this model. For this, a parametric study was conducted with a consideration of main parameters such as Stefan flow, product species, particle evolution, and kinetic parameters.

• 한국유체기계학회 논문집
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• 제5권3호
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• pp.54-59
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• 2002

A commercial CFD code is used to compute the 3-D viscous flow field within the inlet flow concentrator of the newly developed AHU (Air Handling Unit). To improve the performance of the AHU, the inlet air needs to be gradually accelerated to the fan's annular velocity without causing turbulence or flow separation. Three major geometric parameters were selected to specify the inlet shape of the AHU. The performance of the AHU could be measured by the inlet and outlet flow uniformity and the total pressure loss through the inlet flow concentrator. Several numerical calculations were carried out to determine the influence of the geometric parameters on the performance of the AHU. The best geometric values were decided to have efficient inlet shape with analyzing CFD calculation results.

• 한국유체기계학회 논문집
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• 제4권1호
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• pp.38-45
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• 2001

A commercial CFD code is used to compute the 3-D viscous flow field within the impeller of a centrifugal pump. Several preliminary numerical calculations are carried out to determine the influence of the parameters such as the grid systems, the numerical schemes, the turbulence models and the shape of the vaneless diffusers at the design flow rate. The results of the preliminary study are used for the calculation of the off-design flow conditions. The circumferentially averaged results such as the radial and tangential velocities, the exit flow angle, the slip factor, the static pressure and the total pressure are compared with the experimental data at the impeller exit to discuss the influence of the prescribed parameters.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.305-311
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• 2000

A commercial CFD code is used to compute the 3-D viscous flow field within the impeller o( a centrifugal pump. Several preliminary numerical calculations are carried out to determine the influence of the parameters such as the grid systems, the numerical schemes, the turbulence models and the shape of the vaneless diffusers at the design flow rate. The results of the preliminary study are used for the calculation of the off-design flow conditions. The circumferentially averaged results such as the radial and tangential velocities, the exit flow angle, the slip factor, the static pressure and the total pressure are compared with the experimental data at the impeller exit to discuss the influence of the prescribed parameters.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.448-453
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• 2001

A commercial CFD code is used to compute the 3-D viscous flow field within the inlet flow concentrator of the newly developed AHU(Air Handling Unit). To improve the performance of the AHU, the inlet air needs to be gradually accelerated to the fan's annular velocity without causing turbulence or flow separation. Three major geometric parameters were selected to specify the inlet shape of the AHU. Several numerical calculations are carried out to determine the influence of the geometric parameters on the performance of the AHU. The performance of the AHU could be measured by the inlet and outlet flow uniformity and the total pressure loss through the inlet flow concentrator. The optimized nondimensionalized velocity profile through the inlet flow concentrator were used for the design of the AHU with the various volume flow rates.

• 한국항공우주학회지
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• 제45권3호
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• pp.241-251
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• 2017

EFD-CFD 워크샵 중 Case3인 RAE Wing A 형상에 대해 전산유체역학 해석을 수행하였다. 해석자로 3개의 상용 CFD 해석 코드(Star-CCM+, Fluent, CFX)와 오픈 소스 CFD 코드(SU2)를 사용하였다. 격자는 상용 격자 생성 코드인 Pointwise를 이용하여 격자의 수에 따라 4가지를 생성하였다. 마하수 0.4, 0.8에서 는 받음각 2도, 마하수 0.9에서 받음각 1도에서 해석하였다. coarse격자부터 fine 격자까지는 압력계수 곡선과 수직력 계수는 비슷한 결과를 보였으나 항력 계수에서는 차이가 있었다. Star-CCM+과 Fluent의 해석에서 차분법의 차수가 높을수록 충격파의 위치를 앞으로 예측하였다. 수렴에 다다르는 계산시간은 Fluent, Star-CCM+, CFX의 순으로 나타났고 SU2는 이에 비해 수렴하는데 많은 시간이 들었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 춘계학술대회논문집
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• pp.9-18
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• 2009

This paper presents the state of the art of computational structures technology(CST) and comparison of two computational mechanics - CST and CFD, to the CFD engineers. Classical mechanics is based on the five classical axioms which describe the motion and behaviors of the continuum materials like solid structures and fluids. Computational structures technology uses the finite element method to solve the governing equation, whereas finite volume method is generally used in CFD. A few famous commercial structural analysis programs and DIAMOND/IPSAP will be introduced. DIAMOND/IPSAP is the efficient parallel structural analysis package developed by our research team. DIAMOND/IPSAP shows the better performance than the commercial structural analysis software not only in the parallel computing environments but also in a single computer.