• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1472-1475
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• 2004

Current processor power consumption has dramatically increased and already reached 115 Watts. Therefore, Heat sink design needs more high accuracy in 1U server. The target performance of heat sink is very dependent of fin geometry and it is also seriously affected by design conditions such as fan type, air duct shape and heatsink design parameters. The present paper investigates the behavior of heat sink performance under various conditions. The present work addresses pressurized type plane fin heat sinks having dimension of 40 mm by 40 mm by 56 mm fan.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.12
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• pp.3345-3356
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• 1994

A general purpose program, TURBO-3D, for the analysis of 3-D fluid flow in complex geometry has been developed, which employs a standard $k-\varepsilon$ turbulence model and a general nonorthogonal grid system. For the purpose of verification of the program and testing the applicability, turbulent flows in an S-shaped diffuser and turbulent flows over an backward facing step are solved and compared with the earlier results. Comparison with the results by the STAR-CD program has been also made for the same flow configuration and grid structure. The agreements are excellent and hence the program has been verified. Since the present program is applicable only on limited flow phenomena and lacks the pre-and post processor, further improvements toward these directions are being made.

• 한국전산유체공학회:학술대회논문집
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• 2004.10a
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• pp.121-125
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• 2004

The preprocessor - solver - postprocessor software for 2D/Axisymmetric CSCM Upwind Flux Difference Splitting Navier-Stokes code has been developed for undergraduate educational purpose. This computational fluid dynamics (CFD) software allows students to setup, solve, visualize and control dynamically server for their own fluid problems via Internet. The preprocessor Is capable of generating geometry and grid, initial solution data and required solver control parameters. The postprocessor shows vector plot and contour plot with different options while residual plot shows root-mean-square (RMS) error history graphically and retrieves the data from solver interactively. Special feature of the preprocessor is grid generation part which is based on MFC/Visual C++ application and FORTRAN single block grid generator process. Many users can access solver via Internet from client computers and solve desired problems using locally installed pre- and postprocessor and remote powerful solver part.

• Journal of computational fluids engineering
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• v.12 no.2
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• pp.32-36
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• 2007

NUFLEX is a general purpose program for the analysis 3D thermo/fluid flow and pre/post processor in a complex geometry. NUFLEX is composed of various physical models, such as phase change(solidification/melting) and spray, MHD(Magneto Hydraulic Dynamics) models. It is possible to simulate continuous cast iron process and spray droplet breakup/collision phenomenon. For the verification of these models, compared with the experimental data and commercial CFD code's results. The results show good agreements with experimental and comercial CFD codes's results.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.150-157
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• 2008

Bellows are commonly used in piping systems to absorb expansion and contraction in order to reduce stress. Unlike most piping components, bellows consist of a thin-walled shell of revolution with a corrugated meridian, in order to provide the flexibility needed to absorb mechanical movements. It is a composite shell structure consisting of at least one toroidal shell, an annular plate or conical shell. It is difficult to analyze the behavior of bellows because of its complex geometry. Simplified formulas for variable mechanical behaviors of bellows are provided by a standard called EJMA. An automatic design software for bellows is programming by using VBA(Visual Basic for Application) based on EJMA. Bellows engineers can effectively make a decision for bellows geometries because this software provides graphically design results in its post-processor. Bellows design software is expected to give quite a good guidance to practical design. The characteristics of bellows are also investigated through the automatic design process in bellows design software.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.10a
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• pp.65-70
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• 1989

Until recently post-processing of finite element model has been Heavily relied on expensive graphic peripheral devices. For this reason many engineers and researchers can not afford to access to the graphics. with the aid of inexpensive personal computers very econmical post-processor graphics program called MICRO-POST has been developed in conjunction with low-cost printers and plotters. Model geometry or results of analysis for the unlimitted meshes either produced by mainframe or microcomputer can be easily and economi-call presented in a number of different graphic devices. The paper presents the procedure obtaining the device the independent graphics, and the structure and functions of the program. It also describes a new error-preventive dialogue type input technique to control the plot operation in an interactive manner. Through the post-processing examples for the general purpose finite element programs, it demonstrates the usefulness of the program.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.10a
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• pp.1-6
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• 1989

To intergrate finite elements Into CAD enviroment, design oriented structure of the finite element program is desirable. For this purpose a program called CFEP has been developed. Generation of geometry data is independently treated in the program to ease the modification of property or loading data. By conveniently handling the large number of load cases with various load combinations, and by comprehensively reporting the results through inclusive output for the multiple analyses, the program greatly facilitates the design process. Interfacing with interactive graphic post-processor, the results of analyses and final designed values are obtained in a compact and comprehensive manner. The paper also describes necessary tasks for developing such program on the economical microcomputer. Sample output of printed and graphical form well illustrates the procedure.

• 한국전산유체공학회:학술대회논문집
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• 2007.04a
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• pp.99-102
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• 2007

NUFLEX is a general purpose program for the analysis 3D thermo/fluid flow and pre/post processor in a complex geometry. NUFLEX is composed various physical models, such as phase change(solidification/melting) and spray, MHD(Magneto Hydraulic Dynamics) models. It is possible to simulate of continuous cast iron process and spray droplet breakup/collision phenomenon. For the verification of these models, compared with the experimental data and commercial CFD code's results. The results show good agreements with experimental and comercial CFD codes's results.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1419-1424
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• 2003

Impact analysis of TFT-LCD module is very complicated because the structure is assisted with thin, small and non-uniform geometry. Especially, finite element modeling is more difficult and need time-consuming efforts. In this study, we developed LCD Impact Analysis System (LIAS) for the purpose of reducing the analysis time without accuracy reduction. This system contains pre-meshing data, material database, shock condition, auto-reporting etc. PATRAN and DYNA3D is used for meshing and solving. Previously, we performed impact test and reviewed the accuracy of analysis results. Simply we can control design parameters, the procedure such as meshing, running and reporting which are partially auto-prepared. By adopting proposed system, it is expected to achieve efficient impact analysis of LCD module.

• Journal of Welding and Joining
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• v.23 no.4
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• pp.53-58
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• 2005

We designed a weld monitoring system with UV and IR sensors using a embedded DSP controller for implementing a distribution system; running stand alone and communication with outside by industrial standard protocols. Also this system provided a USB port in order to be acquiring data in PC. The user interface program in PC visualized the IR and W data in time, frequency and state space. A correlation of IR and UV signals showed closely related to weld quality. A rapid change of geometry can be found through a moving average filter. And the average value of IR signal at an interval represented a welding width and depth. Through these results, we proposed a monitoring algorithm for a integer type DSP.