• 한국전산유체공학회:학술대회논문집
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• 2005.04a
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• pp.128-134
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• 2005

In the CFD area, the numerical analysis of high Mach number flow over a blunt-body poses many issues. Various numerical schemes have been developed to cover the issues, but the traditional schemes are still used widely due to the complexities of new schemes and intricacy of modifying the established codes. In the present study, the well-known Roe's FDS based on TVD-MUSCL scheme is used for the solution of very high Mach number three-dimensional flows posing carbuncle and non-physical phenomena in numerical analysis. A parametric study was carried out to account for the effects of the entropy fixing, grid configurations and initial condition. The carbuncle phenomena could be easily overcome by the entropy fixing, and the non-physical solution could be eliminated by the use of the modified initial condition regardless of entropy fixing and grid configurations.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.279-280
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• 2003

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.6
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• pp.18-28
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• 2006

Numerical analysis of high Mach number flow over a blunt-body poses many difficulties and various numerical schemes have been suggested to overcome the problems. However, the new schemes were used in the limited fields of applications because of the lack of field experience compared to more than 20 years old numerical schemes and the intricacies of modifying the existing code for the special application. In this study, some tips to overcome the numerical difficulties in solving the 3D high-Mach number flows by using Roe's scheme, the most widely used for the past 25 years and adopted in many commercial codes, were examined without a correction of the algorithm or a modification of the CFD code. The well-known carbuncle phenomena of Riemann solvers could be remedied even for an extremely high Mach number by applying the entropy fixing function and a unphysical solution could be overcome by applying a simply modified initial condition regardless of the entropy fixing and grid configuration.

• Journal of computational fluids engineering
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• v.9 no.2
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• pp.30-35
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• 2004

A numerical study of underexpanded jet and impingement on a wall mounted at various distances from the nozzle exit is presented. The 3-dimensional Wavier-Stokes equations and κ-ω turbulence equations are solved. The grids are constructed as overlapped grid systems to examine the distance effect. The DADI method is applied to obtain steady-state solutions. To avoid numerical instability such as the carbuncle phenomena that sometimes accompany approximate Riemann solver, the HLLE+ scheme is employed for the inviscid flux at the cell interfaces. A goal of this work is to apply a number of two-equation turbulence models based on the w equation to the impinging jet problem.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.229-232
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• 2002

For the purpose of Thermal Protection Material design problem, a numerical analysis of axisymmetric high temperature supersonic impinging jet flows of exhaust gas from combustor on curved surfaces has been accomplished. A modifed CSCM Upwind Navier-Stokes method which is able to cure the carbuncle Phenomena has been developed to study strong shock wave structure and thermodynamic wall properties such as pressure and heat transfer rate on various curved surfaces. The results show that the maximum heat transfer rate which is the most important parameter affecting thermo-chemical surface ablation on the plate did not occur at the center of jet impingement, but rather on a circle slightly away from the center of impingement and the shear stress distribution alone the wall is similar to the wall heat transfer late distribution.