벽면 근처 모델링 방법에 따른 T형 배관 내부의 난류 및 열혼합 분석

국문 초록 (Abstract)

T형 배관의 열피로 평가를 위해 배관 내부의 난류유동 및 온도장을 정확히 예측하는 것은 중요하며, 이를 위해 전산유체역학이 사용된다. 그러나 전산유체역학의 결과는 난류모델, 격자수, 대류항의 차분화 방법 등과 같이 세부적인 적용 방법에 따라 달라질 수 있으며, 특히 열피로와 같이 벽면과의 열전달이 포함된 문제의 경우에는 벽면 근처의 모델링 방법에 따라 그 결과가 크게 영향을 받는다고 알려져 있다. 본 연구에서는 OECD/NEA 벤치마크 문제의 일환으로 수행된 Vattenfall T형 배관 실험을 대상으로 서로 다른 벽면 근처 모델링 방법을 적용하여 수행된 해석결과를 비교·분석함으로써 벽면 근처의 모델링 방법이 T형 배관 내부의 유동 및 온도분포 예측에 미치는 영향에 대해 평가하였다.

다국어 초록 (Multilingual Abstract)

The accurate prediction of turbulent flow and associated thermal fields in a mixing tee is an essential task for thermal fatigue assessment; that requires computational fluid dynamics (CFD). However, CFD could yield various results depending on the methodologies applied, for example turbulence model, mesh resolution, and discretization scheme. In particular, modeling near the wall has been known to affect the results significantly in case of including wall heat transfer such as thermal fatigue problem. In this study, the effects of a modeling approach near the wall on the prediction of flow and temperature distribution in a mixing tee were evaluated by simulating the Vattenfall T-junction test using detached eddy simulation turbulence model and by comparing the results of the analysis.

목차 (Table of Contents)

• 초록
• Abstract
• 1. 서론
• 2. Vattenfall T형 배관 실험
• 3. 벽면법칙과 벽함수
• 4. 수치 모델링
• 5. 결과 및 토의
• 6. 결론
• 참고문헌(References)

참고문헌 (Reference)

1 Sakowitz, A., "Turbulent Flow Mechanisms in Mixing T-junctions by Large Eddy Simulations" 45 : 135-146, 2014

2 Angele, K., "The Vattenfall T-junction Test Facility" 2009

3 Frank, Th., "Simulation of Turbulent and Thermal Mixing in T-junctions Using URANS and Scaleresolving Turbulence Models in ANSYS CFX" 240 : 2313-2328, 2010

4 Rodi, W., "Scrutinizing the k-ε Turbulence Model Under Adverse Pressure Gradient Conditions" 108 : 174-179, 1986

5 Höhne, T., "Scale Resolved Simulations of the OECD/NEA-Vattenfall T-junction Benchmark" 269 : 149-154, 2014

6 Launder, B. E., "On the Computation of Convective Heat Transfer in Complex Turbulent Flows" 110 : 1112-1128, 1988

7 OECD, "OECD/NEA: T-junction Benchmark Specifications (Final Version, July 2009)"

8 Kuczaj, A. K., "Large-eddy Simulation Study of Turbulent Mixing in a T-junction" 240 : 2116-2122, 2010

9 Selvam, P. K., "Large Eddy Simulation on Thermal Mixing of Fluids in a T-junction with Conjugate Heat Transfer" 284 : 238-246, 2015

10 Kim, J., "Large Eddy Simulation of Turbulent Flow in a T-junction" 61 : 180-200, 2012

11 Gritskevich, M. S., "Investigation of the Thermal Mixing in a T-junction Flow with Different SRS Approaches" 279 : 83-90, 2014

12 Casey, M., "ERCOFTAC Special Interest Group on “Quality and Trust in Industrial CFD,” Best Practice Guidelines"

13 Kang, D. G., "Detached Eddy Simulation of Turbulent and Thermal Mixing in a T-junction" 124 : 245-256, 2019

14 Ayhan, H., "CFD Modeling of Thermal Mixing in a T-junction Geometry Using LES Model" 253 : 183-191, 2012

15 ANSYS, "ANSYS CFX-16 User Manual" ANSYS Inc 2015

16 Spalart, P. R., "A New Version of Detached-eddy Simulation, Resistant to Ambiguous Grid Densities" 20 : 181-195, 2006