• Title/Summary/Keyword: 2-D numerical model

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Accuracy Improvement of Analysis Results Obtained from Numerical Analysis Model of Continuously Reinforced Concrete Pavement (연속철근 콘크리트 포장 수치해석 모델의 해석결과 정확도 개선 방법)

  • Cho, Young Kyo;Seok, Jong Hwan;Choi, Lyn;Kim, Seong-Min
    • International Journal of Highway Engineering
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    • v.18 no.1
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    • pp.73-83
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    • 2016
  • PURPOSES : The purpose of this study is to develop a method for improving the accuracy of analysis results obtained from a two-dimensional (2-D) numerical analysis model of continuously reinforced concrete pavement (CRCP). METHODS : The analysis results from the 2-D numerical model of CRCP are compared with those from more rigorous three-dimensional (3-D) models of CRCP, and the relationships between the results are recognized. In addition, the numerical analysis results are compared with the results obtained from field experiments. By performing these comparisons, the calibration factors used for the 2-D CRCP model are determined. RESULTS : The results from the comparisons between 2-D and 3-D CRCP analyses show that with the 2-D CRCP model, concrete stresses can be overestimated significantly, and crack widths can either be underestimated or overestimated by a slight margin depending on the assumption of plane stress or plane strain. The behaviors of crack width in field measurements are comparable to those obtained from the numerical model of CRCP. CONCLUSIONS : The accuracy of analysis results from the 2-D CRCP model can be improved significantly by applying calibration factors obtained from comparisons with 3-D analyses and field experiments.

Study on the Numerical Analysis of Model Ground with SCP (SCP가 타설된 모형지반의 압밀거동에 관한 수치해석적 연구)

  • Hwang, Sung-Pil;Im, Jong-Chul;Kang, Yeoun-Ike;Kwon, Jeong-Geun;Joo, In-Gon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.1224-1231
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    • 2009
  • 1D Analysis have been using Design of SCP in order to improve the soft ground. But 2D Analysis is researching and developing to get more accurate results. Using 2D Analysis, suitable Numerical Analysis Model should be selected and be tested in many situations. In this study, Laboratory Model Tests are analyzed by Numerical Analysis Method. After selecting Numerical Analysis Model, it is being tested many conditions.

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Modeling of Numerical Simulation in Powder Injection Molding Filling Process (분말사출성형 충전공정에 대한 수치모사 모델)

  • 권태현;강태곤
    • Journal of Powder Materials
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    • v.9 no.4
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    • pp.245-250
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    • 2002
  • In this paper we presented numerical method for the simulation of powder injection molding filling process, which is one of the key processes in powder injection molding. Rheological properties of powder binder mixture such as slip phenomena and yield stress were introduced into the numerical analysis model of powder injection molding filling simulation. Numerical model can be classified into two types. One is 2.5D model which can be introduced to a arbitrary thin geometry and the other is full 3D model which can be applied to a general 3D shape. For 2.5D model we showed the validity of our CAE system with several verification examples. Finally we suggested flow analysis model for 3D powder injection molding filling simulation.

Parametric Study of Numerical Prediction of Slamming and Whipping and an Experimental Validation for a 10,000-TEU Containership

  • Kim, Jung-Hyun;Kim, Yonghwan
    • Journal of Advanced Research in Ocean Engineering
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    • v.1 no.2
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    • pp.115-133
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    • 2015
  • This paper describes an approach for the numerical analysis of container ship slamming and whipping and various parameters that influence slamming and whipping. For validation purposes, the numerical analysis results were compared with experimental results obtained as part of the Wave-Induced Loads on Ships Joint Industry Project. Water entry problems for two-dimensional (2D) sections were first solved using a 2D generalized Wagner model (GWM) for various drop conditions and geometries. As the next step, the hydroelastic numerical analysis of a 10,000-TEU container ship subjected to slamming and whipping loads in waves was performed. The analysis method used is based on a fully coupled model consisting of a three-dimensional (3D) Rankine panel model, a 3D finite element model (FEM), and a 2D GWM, which are strongly coupled in the time domain. Parametric studies were carried out in both numerical and experimental tests with various forward speeds, wave heights, and wave periods. The trends observed and the validity of the numerical analysis results are discussed.

A Study on the Flow Characteristics in Urban Stream Using 3-D Numerical Model (3차원 수치모형을 이용한 도시하천의 흐름특성에 관한 연구)

  • Yoon, Sun-Kwon;Kim, Jong-Suk;Moon, Young-Il;Lee, Il-Ju
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1287-1292
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    • 2007
  • Recently, the frequency of unexpecting heavy rains has been increased due to abnormal climate and extreme rainfall. There was a limit to analyze 1D or 2D stream flow that was applied simple momentum equation and fixed energy conservation. Therefore, hydrodynamics flow analysis in rivers has been needed 3D numerical analysis for correct stream flow interpretation. In this study, CFD model on FLOW-3D was applied to stream flow analysis, which solves three dimenson RANS(Reynolds Averaged Navier-Stokes Equation) control equation to find out physical behavior and the effect of hydraulic structures. Numerical simulation accomplished those results was compared by using turbulence models such as ${\kappa}-{\varepsilon}$, RNG ${\kappa}-{\varepsilon}$ and LES. Those numerical analysis results have been illustrated by the turbulence energy effects, velocity of flow distributions, water level pressure distributions and eddy flows around the piers at Jangwall bridge in urbarn stream.

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On Comparison between 2-D and 3-D Numerical Models used to Analyze the Wave Field around a Permeable Submerged Breakwater (투과성잠제 주변의 파동장 해석을 위한 2-D 및 3-D 수치계산의 비교)

  • Hur, Dong-Soo;Choi, Dong-Seok;Lee, Woo-Dong;Yeom, Gyeong-Seon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.20 no.4
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    • pp.363-371
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    • 2008
  • The aim of this study is to compare the numerical results obtained by 2-D and 3-D models which are used to examine the wave field around a permeable submerged breakwater. At first, the numerical model, which is able to consider the flow through a porous medium with inertial, laminar and turbulent resistance terms and determine the eddy viscosity with LES turbulent model, is used and validated by comparing with existing experimental data. And then, the numerical test on the wave field around a permeable submerged breakwater is performed. It is revealed from the numerical results that, at the onshore side of the submerged breakwater, the wave height by 2-D analysis is higher than that by 3-D analysis. Also, the time-averaged mean flow around a submerged breakwater is discussed in detail.

The behaviour of structures under fire - numerical model with experimental verification

  • Toric, Neno;Harapin, Alen;Boko, Ivica
    • Steel and Composite Structures
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    • v.15 no.3
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    • pp.247-266
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    • 2013
  • This paper presents a comparison of results obtained by a newly developed numerical model for predicting the behaviour of structures under fire with experimental study carried out on heated and simply supported steel beam elements. A newly developed numerical model consists of three submodels: 3D beam model designed for calculating the inner forces in the structure, 2D model designed for calculation of stress and strain distribution over the cross section, including the section stiffness, and 3D transient nonlinear heat transfer model that is capable of calculating the temperature distribution along the structure, and the distribution over the cross section as well. Predictions of the calculated temperatures and vertical deflections obtained by the numerical model are compared with the results of the inhouse experiment in which steel beam element under load was heated for 90 minutes.

Static Behavior of Reinforced Railway Roadbed by Geotextile Bag (지오텍스타일 백으로 보강된 철도노반의 정적거동 분석)

  • Lee, Dong-Hyun;Shin, Eun-Chul
    • Journal of the Korean Society for Railway
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    • v.9 no.2 s.33
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    • pp.180-186
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    • 2006
  • In this study, a large-scale laboratory model test, 2-D and 3-D numerical analyses were conducted to verify the reinforcement effect by utilizing geotextile bag on the railway roadbed. Static loading which simulated train load was applied on the geotextile bag-reinforced railway roadbed and also unreinforced railway roadbed, Computer program named Pentagon which is a part of FEM programs was used in the numerical analysis. Based on the results of laboratory test, 2-D and 3-D numerical analyses, the effect of load distribution and settlement reduction was found to be depending on the geotextile characteristics, tensile strength of geotextite, and interface friction angle between geotextile bags. In general, the result of 2-D and 3-D numerical analyses shows lower value than that of laboratory test. Also, the result of 3-D numerical analyses shows lower value than that of 2-D numerical analyses because of its stress transfer effect.

Numerical study of turbulent wake flow behind a three-dimensional steep hill

  • Ishihara, Takeshi;Hibi, Kazuki
    • Wind and Structures
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    • v.5 no.2_3_4
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    • pp.317-328
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    • 2002
  • A numerical investigation on the turbulent flows over a three-dimensional steep hill is presented. The numerical model developed for the present work is based on the finite volume method and the SIMPLE algorithm with a non-staggered grid system. Standard $k-{\varepsilon}$ model and Shih's non-linear model are tested for the validation of the prediction accuracy in the 3D separated flow. Comparisons of the mean velocity and turbulence profiles between the numerical predictions and the measurements show good agreement. The Shih's non-linear model is found to predict mean flow and turbulence better than the Standard $k-{\varepsilon}$. Flow patterns have also been examined to explain the difference in the cavity zone between 2D and 3D hills.

Direct 3-D Numerical Simulation of Overtopping on the Coastal Structures (해역구조물을 통한 월파의 3차원 수치계산기법의 개발)

  • Hur, Dong-Soo;Kim, In-Chul
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.18 no.4
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    • pp.383-389
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    • 2006
  • In three dimensional wave field, a direct numerical simulation model, which is able to handle free-fall and slope-fall of a waterdrop due to overtopping, is proposed to evaluate the overtopping rate on the coastal structures like an absorbing revetment. A comparison between the numerical model and existing experimental results for overtopping rate was made to validate the proposed numerical model's accuracy, and showed fairly good agreement between them. It is confirmed in numerical and hydraulic(existing) model test that the overtopping quantity on a absorbing revetment becomes larger with an increase in Ursell number. Also, the overtopping rate estimated by 3-D numerical model is compared with it obtained by 2-D numerical model.