• 제목/요약/키워드: Quick Scheme

검색결과 135건 처리시간 0.019초

Hybrid-QUICK Scheme Using Finite-Volume Method

  • Choi, Jung-Eun
    • Journal of Hydrospace Technology
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    • 제2권2호
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    • pp.57-67
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    • 1996
  • The formulation for hybrid-QUICK scheme of convective transport terms in finite-volume calculation procedure is presented. Source terms are modified to apply the hybrid-QUICK scheme. Test calculations are performed for wall-driven cavity flow at Re=$10_2$, $10_3$, and $10_4$. These include the evaluation of boundary conditions approximated by third-order finite difference scheme. The stable and converged solutions are obtained without unsteady terms in the momentum equations. The results using hybrid-QUICK scheme show no difference with those using hybrid scheme at low Re ($=10_2$) and are better at higher Re ($10_3$, and $10_4$).

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비정렬 유한체적법을 위한 QUICK법의 수정 (Modification of QUICK Scheme for Unstructured Grid Finite Volume Method)

  • 강동진;배상수
    • 대한기계학회논문집B
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    • 제24권9호
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    • pp.1148-1156
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    • 2000
  • The QUICK scheme for convection terms is modified for unstructured finite volume method by using linear reconstruction technique and validated through the computation of two well defined laminar flows. It uses two upstream grid points and one downstream grid point in approximating the convection terms. The most upstream grid point is generated by considering both the direction of flow and local grid line. Its value is calculated from surrounding grid points by using a linear construction method. Numerical error by the modified QUICK scheme is shown to decrease about 2.5 times faster than first order upwind scheme as grid size decreases. Computations are also carried out to see effects of the skewness and irregularity of grid on numerical solution. All numerical solutions show that the modified QUICK scheme is insensitive to both the skewness and irregularity of grid in terms of the accuracy of solution.

비압축성 Navier-Stokes 방정식의 해석을 위한 MQUICK 상류해법 (MQUICK Upwind Scheme for the Incompressible Navier-Stokes Equations)

  • 신병록;정소추 이명
    • 한국전산유체공학회지
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    • 제4권1호
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    • pp.41-52
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    • 1999
  • 이 논문에서는, QUICK해법의 불안정성을 개량하므로써, 수치계산에 있어서 수렴이 빠르고, 수치적으로 안정한 계산을 할 수 있는 새로운 MQUICK 상류해법을 제안하고, 이를 비압축성 층류유동의 계산에 적용하였다. 또한, 해법의 정확성, 안정성, 수렴속도에 대한 검토를 통하여 본 MQUICK 상류해법의 유효성과 타당성이 평가되었다. 이 해법에서는 인공산일의 가감을 조절하기 위하여 가중계수 α를 써서 정식화 하였고, 위의 검토를 통하여 α의 최적값을 조사하였다. 이 해법을 SMAC 음해법에 적용하여 2 차원 공동유동, 3 차원 덕트유동과 같은 몇몇 표준문제를 계산하고, 계산된 결과를 실험값 또는, 3 차 정확도의 상류해법 및 QUICK해법에 의한 결과 들과 비교 하므로써, 본 MQUICK 상류해법이 위의 다른 해법에 비하여 안정하고, 유효성이 높은 해법임을 확인 하였다.

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액체금속로 내부 열유동해석을 위한 대류항처리법 평가 (Evaluation of Convection Schemes for Thermal Hydraulic Analysis in a Liquid Metal Reactor)

  • 최석기;김성오;김의광;어재혁;최훈기
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2002년도 추계 학술대회논문집
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    • pp.64-69
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    • 2002
  • A numerical study has been peformed for evaluation of convection schemes for thermal hydraulic analysis in a liquid metal reactor Four convection schemes, HYBRID, QUICK, SMART and HLPA included in the CFX-4 code are considered. The performances of convection schemes are evaluated by applying them to the five test problems. The accuracy, stability and convergence are tested. It is shown that the HYBRID scheme is too diffusive, and the QUICK scheme exhibits overshoots and undershoots, and the SMART scheme shows convergence oscillations, and the HLPA scheme preserves the boundedness without causing convergence oscillations. The accuracies of SMART, QUICK and HLPA schemes are comparable. Thus, the use of HLPA scheme is highly recommended for thermal hydraulic analysis in a liquid metal reactor.

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비정상상태 복사열전달 해석을 위한 2 차 상류스킴 및 QUICK 스킴의 유한체적복사해법 적용 연구 (Transient Radiative Heat Transfer Using Finite Volume Method with 2-Order Upwind Scheme and QUICK Scheme)

  • 변도영;이건호;김만영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1294-1299
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    • 2004
  • Transient radiative heat transfer is analyzed in a one-dimensional slab using finite volume method (FVM). In this study, the step, $2^{nd}$ order upwind, and QUICK schemes are used for incident diffuse radiation and collimated beam, respectively. The results for diffuse radiation show that all schemes applied in this study give good agreements with available published results. In case of collimated beam, however, the results show deviations from the analytical solutions. To successfully describe the propagations of collimated beam, shock capturing schemes such as TVD scheme are need to be developed.

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PSIC 모델을 이용한 액체로켓의 연소실내 분무유동 해석 (Analysis for Spray Flow Using PSIC Model in Combustion Chamber of Liquid Rocket Engine)

  • 정대권;노태성
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2006년도 제26회 춘계학술대회논문집
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    • pp.253-256
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    • 2006
  • 액체로켓의 연소실내 분무연소 현상을 해석하기 위해 비연소 반응의 연료와 산화제 액적의 분무유동을 해석하였다. 분무연소 모델로 DSF 모델과 Euler-Lagrange 방법을 사용하였다. 액적과 가스상 그리고 증발한 기체상의 커플효과는 PSIC 모델을 사용하여 계산하였으며 수치 해석 방법으로 SIMPLER 알고리즘과 QUICK Scheme을 사용하였다. 해석결과 연소실내 속도와 온도 분포를 알 수 있었고, 연료와 산화제의 몰분율 또한 알 수 있었다.

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1차원 비정상상해 복사열전달 해석을 위한 2차 상류스킴 및 QUICK 스킴의 유한체적복사해법 적용 연구 (1- Dimensional Transient Radiative Heat Transfer Using Finite Volume Method with 2-Order Upwind Scheme and QUICK Scheme)

  • 이건호;김만영;변도영
    • 대한기계학회논문집B
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    • 제30권3호
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    • pp.201-207
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    • 2006
  • Transient radiative heat transfer is analyzed in a one-dimensional slab using finite volume method (FVM). In this study, the step, $2^{nd}$ order upwind, and QUICK schemes are used for incident diffuse radiation and collimated beam, respectively. The results fer diffuse radiation show that all schemes applied in this study give good agreements with available published results. In case of collimated beam however, the results show deviations from the analytical solutions. To successfully describe the propagations of collimated beam shock capturing schemes such as TVD scheme are need to be developed.

PISO 알고리즘을 이용한 밀폐공간내에서의 유동 및 혼합대류에 관한 연구 (A Numerical Study of Initial Unsteady Flow and Mixed Convection in an Enclosed Cavity Using the PISO Algorithm)

  • 최영기;정진영
    • 설비공학논문집
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    • 제2권1호
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    • pp.63-73
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    • 1990
  • A numerical analysis of initial unsteady state flow and heat transfer in an enclosed cavity has been performed by the Modified QUICK Scheme. The stable QUICK Scheme which modified the coefficient always to be positive is included in this numerical analysis. The implicit method is applied to solve the unsteady state flow; between iterations the PISO (Pressure - Implicit with Splitting of Operators) algorithm is employed to correct and update the velocity and pressure fields on a staggered grid. The accuracy of the Modified QUICK Scheme is proved by applying fewer grid systems than those which Ghia et al. and Davis applied. The initial unsteady mixed convection in an enclosed cavity is analyzed using the above numerical procedure. This study focuses on the development of the large main vortex and secondary vortex in forced convection, the effects of the Rayleigh Number in natural convection and the relative direction of the forced and natural convection.

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시간과 격자 크기 변화에 따른 원주후류해석의 경제적 수치기법 (Proper Numerical Scheme to Solve the Flow Past a Circular Cylinder with Time and Grid Size Variations)

  • 맹주성;김용대;최일곤
    • 대한기계학회논문집B
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    • 제24권5호
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    • pp.652-659
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    • 2000
  • The purpose of this study is to present the most effective numerical scheme to calculate the unsteady flows. In order to calculate the flow quantities of flow past a circular cylinder, Three-time level and five convective schemes are applied to unsteady and convective terms, respectively. The values obtained are compared with those from the existing experimental and numerical studies. At Reynolds numbers up to 160, time intervals can be expanded 10 times of Implicit Euler scheme using Three-time level method, and it is found that QUICK and CUI schemes work much stable than others even if less grid density conditions. The combination of Three-time level and QUICK scheme gives high resolutions for laminar unsteady problems with PC level.

유한차분 도식에 따른 건물 계단통에서의 3차원 부력 난류유동 수치해석 (Numerical analysis of 3-dimensional buoyant turbulent flow in a stairwell model with three different finite differencing schemes)

  • 명현국
    • 설비공학논문집
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    • 제11권1호
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    • pp.73-80
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    • 1999
  • This paper describes a numerical study of three-dimensional buoyant turbulent flow in a stairwell model with three convective differencing schemes, which include the upwind differencing scheme, the hybrid scheme and QUICK scheme. The Reynolds-averaged Navier-Stokes and energy equations are solved with a two-equation turbulence model. The Boussinesq approximation is used to model buoyancy terms in the governing equations. Three-dimensional predictions of the velocity and temperature fields are presented and are compared with experimental data. Three-dimensional simulations with each scheme have predicted the overall features of the flow fairly satisfactorily. A better agreement with experimental is achieved with QUICK scheme.

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