• 한국가시화정보학회지
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• 제2권2호
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• pp.20-24
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• 2004

Recent advances in CFD technique along with a rapid growth of computer resources provide valuable opportunities for developing an accurate way of visualizing turbulent structures. Not only this visualization technique made it possible to check the validity of many of theoretical achievements of the past but also it pushes the current turbulence research to a new paradigm. A brief history of visualization study will be summarized and discussed.

• 대한공간정보학회지
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• 제19권4호
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• pp.13-21
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• 2011

3D City 모델로부터 CFD 모델 입력자료를 생성하여 모델링 품질을 향상시키고 CFD 모델링 결과를 3D 모델과 통합하여 사실적이고 쉽게 인지할 수 있는 시각화 방법에 대하여 연구하였다. 국토지리정보원에서 구축한 3D City 모델을 이용해 세밀도와 정확도가 향상된 CFD 모델 입력자료를 생산하여 적용함으로써 상세한 도시공간구조를 반영하는 향상된 CFD 모델을 생산하였다. CFD_NIMR_SNU 모델로부터 바람의 흐름과 오염물질 확산을 시뮬레이션 하였으며 3D City Model과 CFD 모델을 통합하여 동적으로 시각화 하였다. 본 대기환경 시각화 도구는 도시기후 계획 및 관리에 있어 의사결정을 위한 시각적 소통능력을 향상시켜 비용과 시간을 최소화할 것이다.

• 한국산학기술학회논문지
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• 제2권1호
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• pp.43-51
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• 2001

메타컴퓨팅 시스템은 분산된 컴퓨팅 자원들과 가시화 장비들을 통합하여 사용자가 편리하고 신속하게 작업을 처리할 수 있게 해 주는 환경이다. 본 연구에서는 전산유체역학(CFD : Computational Fluid Dynamics) 프로그램 개발자들을 위한 메타컴퓨팅 시스템을 개발하였다. 본 시스템에서 사용자는 프로그램을 컴퓨팅 자원에 분산시키고 분산환경에서 컴파일 할 수 있으며 프로그램구조에 적합한 컴퓨팅 자원에서 그 결과를 동영상을 통하여 얻을 수 있다. 본 연구에서는 다음과 같이 두 가지 연구를 수행하였다. 전산유체역학 프로그램의 구조를 이용한 자원선정에 대한 연구, 요소시스템 통합연구. 컴퓨팅 자원 선정을 위해 전산유체역학 프로그램의 구조적인 특징을 이용하였고 실시간 가시화를 위하여 기존의 가시화 도구를 수정하여 통합하였다.

• 한국항공운항학회지
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• 제12권3호
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• pp.13-24
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• 2004

It is easier to view flow visualization by using a water tunnel rather than a smoke wind tunnel because of low speed at same Reynolds number. Using a water tunnel also produces more definite flow visualization by the use of various color dyes. The flow uniformity in test section is very significant for accuracy of the test because most flow experiments elicit results through the installation of a model in uniform flow. The purpose of small-size desktop-type water tunnel is not to produce quantitative measurements, but rather to give a visualization of the fluid flow phenomenon. However, uniformity in the test section affects the accuracy of the results. Accordingly, this research estimates uniformity in a water tunnel test section by using the commercially available CFD code FLUENT. Results of the CFD analysis show that the flow uniformity of the test section is good.

• Journal of Mechanical Science and Technology
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• 제15권12호
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• pp.1794-1800
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• 2001

Mass conservation is a key issue for accurate streamline and stream surface visualization of flow fields. This paper complements an existing method (Feng et al. 1997) for CFD velocity fields defined at discrete locations in space that uses dual stream functions to generate streamlines and stream surfaces. Conditions for using the method have been examined and its limitations defined. A complete set of dual stream functions for all possible cases of the linear fields on which the method relies are presented. The results in this paper are important for developing new methods for mass conservative streamline visualization from CFD and using the existing method.

• 한국전산유체공학회지
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• 제20권4호
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• pp.28-35
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• 2015

BARAM system that means 'wind' in Korean has been established as a virtual wind tunnel system for aircraft design. Its aim is to provide researchers with easy-to-use, production-level environment for all stages of CFD simulation. To cope with this goal an integrated environment with a set of CFD solvers is developed and coupled with an highly-efficient visualization software. BARAM has three improvements comparing with previous CFD simulation environments. First, it provides a new automatic mesh generation method for structured and unstructured grid. Second, it also provides real-time visualization for massive CFD data set. Third, it includes more high-fidelity CFD solvers than commercial solvers.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 PARALLEL CFD 2006
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• pp.209-210
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• 2006

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 추계 학술대회논문집
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• pp.82-87
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• 2003

Post-processing programs play an important role in the CFD data visualization and analysis. A variety of post-processing softwares have been developed and are being used in the CFD community. Developing a good quality of post-processing program requires dedication and efforts. In this paper an experience obtained through previous studies and developing post-processing programs are introduced which includes data structure and visualization algorithms.

• 한국가시화정보학회지
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• 제9권4호
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• pp.47-53
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• 2011

A water driven ejector loop was designed and constructed for air absorption. The used ejector was horizontally installed in the loop and annular water jet at the throat entrained air through the circular pipe placed at the center of the ejector. Wide range of water flow rate was provided using two kinds of pumps in the loop. The tested range of water flow rate was 100${\ell}$ /min to 1,000 ${\ell}$/min. Two-phase flow inside the ejector loop was simulated by CFD analysis. Homogeneous particle model was used for void fraction prediction. Water and air flow rates and pressure drop through the ejector were automatically recorded by using the LabView based data acquisition system. Flow characteristics and air bubble velocity field downstream of the ejector were investigated by two-phase flow visualization and PIV measurement based on bubble shadow images. Overall performance of the two-phase ejector predicted by the CFD simulation agrees well with that of the experiment.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.270-275
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• 2001

The characteristics of flow in dividing regions are precise, therefore their classification is very important not only in industry but also in hydrodynamics. By now, many studies of flow in dividing regions have been peformed, but flow characteristics that use visualization In dividing regions have not been studied. The present study of the PIV and the CFD exhibit average velocity distributions, kinetic energy distributions and total pressure distributions etc of the total flow field due to the development of the accurate visualization optical laser and of optical equipment. Also, PIV is accurate with the flows characteristics of the dividing region as continuous analysis is done using input equipment. The study analyzes velocity vector field, turbulence kinetic energy, turbulence viscosity of dividing regions with flow for visualization of the PIV and the CFD measurement in a dividing rectangular ducts.