http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
S. Singh(사티비르 싱),R.S. Myong(명노신) 한국전산유체공학회 2017 한국전산유체공학회지 Vol.22 No.2
On the basis of a high order discontinuous Galerkin method, the bulk viscosity effects on shock-vortex interaction are investigated by solving the two-dimensional conservational laws for diatomic gases. A comparison of shock-vortex interaction in monatomic and diatomic gases is conducted. In the case of diatomic gas flow, the substantially strengthened enstrophy evolution is observed. In addition, the effects of interaction parameters such as shock and vortex Mach numbers on shock-vortex interaction are examined. The results show that the strong shock-vortex interaction associated with high shock and vortex Mach numbers can result in higher enstrophy.
DEVELOPING A LATTICE BOLTZMANN ANALYSIS CODE IN GENERALIZED COORDINATE
R. Murugesan(람키 무르게산),R.S. Myong(명노신),J.H. Park(박재현) 한국전산유체공학회 2014 한국전산유체공학회 학술대회논문집 Vol.2014 No.11
The final goal of our work is to develop a Lattice Boltzmann Method (LBM) analysis code for generalized coordinate system. As a first step, in this paper the developed code is validated/verified for well-known benchmark problems such as a 2-D lid-driven cavity flow, Couette flow, Poiseuille flow by using Cartesian coordinates. Throughout this paper D2Q9 lattice modeling is employed. The features of boundary conditions are also discussed.
정성기(S. K. Jung),명노신(R. S. Myong),조태환(T. H. Cho),박경린(G. R. Park),강태우(T. W. Kang) 한국전산유체공학회 2010 한국전산유체공학회 학술대회논문집 Vol.2010 No.11
Ice accretion on aircraft surface can greatly deteriorate the aerodynamic performance of aircraft. Especially, air flows around a wing at glaze ice conditions are very complex and can suffer large aerodynamic penalties. Complicated horn shapes are usually found on the surfaces at glaze ice conditions by coupling effects of heat flux and shear stress. Therefore, the conventional structured CFD method has difficulty in the prediction of glaze ice shape due to its limitation on handling complex geometry. For example, negative cell volumes can be generated in the structured grids in the process of grid regeneration. In order to overcome this limitation, unstructured CFD method was employed to calculate an Eulerian-based droplet field and ice accretion on the surfaces. The developed codes were then compared with experimental data. It was shown that the collective efficiency and iced shape were in good agreement with previous results.
항공기 결빙 예측을 위한 Eulerian 기반 액적 충돌 및 결빙 증식 코드
정성기(S.K. Jung),명노신(R.S. Myong),조태환(T.H. Cho) 한국전산유체공학회 2010 한국전산유체공학회지 Vol.15 No.2
As a step toward accurate prediction of droplet impingement and ice accretion on aircraft, an Eulerian-based droplet impingement and ice accretion code for air flows around an airfoil containing water droplets is developed. A CFD solver based on the finite volume method was also developed to solve the clean airflow. The finite-volume-based approach for simulating droplet impingement on an airfoil was employed owing to its compatibility with the CFD solver and robustness. For ice accretion module, a simple model based on the control volume is combined with the droplet impingement module that provides the collection efficiency. To validate the present code, it is compared with NASA Glenn IRT (Icing Research Tunnel) experimental data and other well-known icing codes such as LEWICE and FENSAP-ICE. It is shown that the collection efficiency and shape of ice accretion are in good agreement with previous experimental and simulation results.
에어포일의 결빙에 의한 실속 및 항력 특성 변화에 관한 CFD 해석
정성기(S.K. Jung),신성민(S.M. Shin),명노신(R.S. Myong),조태환(T.H. Cho) 한국전산유체공학회 2009 한국전산유체공학회 학술대회논문집 Vol.2009 No.4
The aerodynamic performance of aircraft in icing condition can deteriorate considerably by contamination of aerodynamic and propulsive systems due to icing accretions on aircraft surfaces. A computational analysis based on the Eulerian description was performed on an airfoil to investigate effects of ice accretions on airfoil aerodynamics. A water droplet with liquid water concentration (0.00075㎏/㎥) and mean volume diameter (20㎛) was considered and applied to various angles of attack to investigate the stall angle decrease and the drag increment.
세장형 물체 주의 고앙각 유동의 비대칭 와류 및 측력 특성에 관한 수치적 연구
정성기(S.K. Jung),정재홍(J.H. Jung),명노신(R.S. Myong),조태환(T.H. Cho) 한국전산유체공학회 2006 한국전산유체공학회지 Vol.11 No.3
Flow around a guided missile in high maneuver. i.e. at a high angle of attack. shows complex phenomena. It is well known that even in geometrically symmetric conditions the flow around a missile at high angles of attack can generate unexpected large side forces and yaw moments due to asymmetric vortices. In this paper, a CFD code (FLUENT) based on the Navier-Stokes equations was used for the numerical analysis to find a suitable numerical mechanism for generation of asymmetric vortices. It is shown that a numerical technique of applying different surface roughness to a specific area of the missile nose surface gives the best fit in comparison with the experimental results. In addition, a numerical investigation of variations of side forces and pressure distributions with angle of attack and roll angle was conducted for the purpose of identifying the source of vortex asymmetries.
등속도로 하강중인 회전 낙하산의 공력특성에 관한 수치적 연구
제상언(S.E. Je),정성기(S.G. Jung),곽상혁(S.H. Kwag),명노신(R.S. Myong),조태환(T.H. Cho) 한국전산유체공학회 2006 한국전산유체공학회지 Vol.11 No.1
In this paper a method for analysing aerodynamic characteristics of a rotating parachute in steady descending motion is presented Because of a complex geometric configuration of the parachute associated with side vents and discontinuous skirts, special procedure was adopted to handle the geometry in the analysis. A panel method was successfully applied to the present problem and yielded good results using above procedure. A CFD code using the full Navier-Stokes equations was also applied and produced good results. Parachute free drop and wind tunnel tests were performed to determine the fully developed canopy configuration and aerodynamic characteristics. The method can be used for optimizing the parachute size and side vent configurations.
정성기(S.K. Jung),오진근(J.G. Oh),전수환(S.H. Chun),문혁(H. Moon),명노신(R.S. Myong),조태환(T.H. Cho) 한국전산유체공학회 2010 한국전산유체공학회 학술대회논문집 Vol.2010 No.5
Ice accretion on aircraft surface can greatly impair the aerodynamic performance of aircraft. As an alternative to the traditional Lagrangian particle tracking approach, an Eulerian-based droplet impingement and ice accretion code for air flows containing water droplets was developed. A CFD solver was also developed to solve the clean airflow. The results of present method were compared with experimental data and previous icing codes such as LEWICE and FENSAP-ICE and were confirmed to show good agreement each other in qualitative and quantitative ways.