• Title/Summary/Keyword: Dimensional model

Search Result 9,240, Processing Time 0.038 seconds

Computational analysis of cancer angiogenesis using two dimensional model (2차원 모델을 이용한 암의 혈관생성에 대한 수치적 연구)

  • Shim Eun Bo;Ko Hyung Jong;Deisboeck Thomas
    • Proceedings of the KSME Conference
    • /
    • 2002.08a
    • /
    • pp.709-710
    • /
    • 2002
  • Cancer angiogenesis is simulated using a two dimensional model. Governing equation of angiogenesis is a TAE (Tumor angiogenesis factor) conservation equation in time and space. A stochastic process model is utilized to simulate vessel formation, proliferation, and migration to a cancer pellet. Numerical results are presented especially in case of growing cancer.

  • PDF

A Study on the Development of a Three Dimensional Numerical Model for the Casting Processes (주조공정의 수치해석을 위한 3차원 전산모델 개발에 관한 연구)

  • ;S.Patankar
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.26 no.10
    • /
    • pp.1436-1444
    • /
    • 2002
  • A three dimensional numerical model was developed to analyze the mold filling and solidification processes straightforwardly in a casting processes. On the basis of the SIMPLER algorithm, the VOF method and the Equivalent Specific Heat method were adopted to deal with the free surface behavior and the latent heat evolution. The complete model has been validated using exact solutions and experimental results. The importance of three-dimensional effects has been highlighted by comparing the results from the three-dimensional analysis with those given by a two-dimensional analysis.

A Numerical Study on Plate-Type Heat Exchanger Using One-Dimensional Flow Network Model and Porous-Media Model (1차원 유동 네트워크 모델 및 다공성매질 모델을 이용한 판형 열교환기의 수치적 연구)

  • Park, Jaehyun;Kim, Minsung;Min, June Kee;Ha, Man Yeong
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.28 no.1
    • /
    • pp.21-28
    • /
    • 2016
  • A typical heat exchanger, found in many industrial sites, is made up of a large number of unitary cells, which causes difficulties when carrying out full-scale three-dimensional numerical simulations of the heat exchanger to analyze the aero-thermal performance. In the present study, a three-dimensional numerical study using a porous media model was carried out to evaluate the performance of the heat exchanger modelled in two different ways : full-scale and simplified. The pressure drop in the air side and gas side along with the overall heat transfer rate were calculated using a porous media model and the results were then compared to results obtained with a one-dimensional flow network model. The comparison between the results for two different geometries obtained using a porous media model and a one-dimensional flow network model shows good agreement between the simplified geometry and the one-dimensional flow network model. The full-scale geometry shows reasonable differences caused by the geometry such as sudden expansion and contraction.

FE-based Strip Mean Temperature Prediction On-Line Model in Hot Strip Finishing Mill by using Dimensional Analysis (차원해석을 통한 열간 사상압연중 온도해석모델 개발)

  • 이중형;곽우진;황상무
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2003.05a
    • /
    • pp.176-179
    • /
    • 2003
  • The mean temperature prediction of strip is very important in hot strip finishing mill because of affecting on product quality and shape. Also, temperature can be used by basic information in other on-line control models with affecting control accuracy in factory. So, FE based on-line temperature model was developed for predicting strip mean temperature accurately in various process conditions and factory environments. There are many variables in affecting strip mean temperature in on-line states of factory. But some problems are occurred in considering all variables for making temperature model because of the bad efficiency of regression or fitting analysis. In this report, we have adopted dimensional analysis for solving these problems. We have many variables with dimensions affecting strip temperature but we are able to make non-dimensional variables less than dimensional variables from the combination of dimensional variables caused by PI-Theorem in fluid mechanics. The developed models are divided by two parts. The one is interstand temperature prediction model. The other is roll gap temperature model.

  • PDF

Construction and Measurement of Three-Dimensional Knee Joint Model of Koreans (한국인의 3차원 무릎관절 구축 및 형상 측정)

  • Park, Ki-Bong;Kim, Ki-Bum;Son, Kwon;Suh, Jeung-Tak;Moon, Byung-Young
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.28 no.11
    • /
    • pp.1664-1671
    • /
    • 2004
  • It is necessary to have a model that describes the feature of the knee Joint with a sufficient accuracy. Koreans, however, do not have their own knee joint model to be used in the total knee replacement arthroplasty. They have to use European or American models which do not match Koreans. Three-dimensional visualization techniques are found to be useful in a wide range of medical applications. Three-dimensional imaging studies such as CT(computed tomography) and MRI(magnetic resonance image) provide the primary source of patient-specific data. Three-dimensional knee joint models were constructed by image processing of the CT data of 10 subjects. Using the constructed model, the dimensions of Korean knee joint were measured. And this study proposed a three-dimensional model and data, which can be helpful to develop Korean knee implants and to analyze knee joint movements.

An improved model of compaction grouting considering three-dimensional shearing failure and its engineering application

  • Li, Liang;Xiang, Zhou-Chen;Zou, Jin-Feng;Wang, Feng
    • Geomechanics and Engineering
    • /
    • v.19 no.3
    • /
    • pp.217-227
    • /
    • 2019
  • This study focuses on an improved prediction model to determine the limiting grouting pressure of compaction grouting considering the ground surface upheaval, which is caused by the three-dimensional conical shearing failure. The 2D-dimensional failure curve in Zou and Xia (2016) was improved to a three-dimensional conical shearing failure for compaction grouting through coordinate rotation. The process of compaction grouting was considered as the cavity expansion in infinite Mohr-Coulomb (M-C) soil mass. The prediction model of limiting grouting pressure of compaction grouting was proposed with limit equilibrium principle, which was validated by comparing the results in El-Kelesh et al. (2001) and numerical method. Furthermore, using the proposed prediction model, the vertical and horizontal grouting tube techniques were adopted to deal with the subgrade settlement in Shao-huai highway at Hunan Provence of China. The engineering applicability and effectiveness of the proposed model were verified by the field test. The research on the prediction model for the limiting grouting pressure of compaction grouting provides practical example to the rapid treatment technology of subgrade settlement.

Development of Two-Dimensional Sediment Transport Model Using Observed Erosion Rate (침식률 측정자료를 이용한 2차원 퇴적물 수송모형의 개발)

  • Jeong, Tae-Seong
    • Journal of Korea Water Resources Association
    • /
    • v.34 no.6
    • /
    • pp.687-699
    • /
    • 2001
  • A 2-dimensional numerical sediment transport model has been developed by using erosion rates observed by SEDFLUME. The model un boundary-fitted coordinate can reduce inaccuracy of sediment model with accurate erosion data. Suspended transport and bed load transport are included in the model together. The model results gave good agreement with particle size distributions in 1-d channel and was more accurate than that of HIDAS of 1-dimensional model. The model applied to an enlarging channel to check model performance in 2-dimensional domain. Bed coarsening reduced erosion and deposition.

  • PDF

A Study on the Topography Change of Hyeya River and Jinha Beach (회야강 하구 및 진하해수욕장의 지형변화에 관한 연구)

  • 민병형;민일규;이동수
    • Journal of Ocean Engineering and Technology
    • /
    • v.8 no.1
    • /
    • pp.84-95
    • /
    • 1994
  • In recent years Jin-Beach and Hyeya River mouth have experienced severe erosion phenomena. The cause of erosion is examined using a 3-dimensional nunumerical sediment transport model. The model is composed of three components : wave model, wave-induced current model and 3-dimensional sediment transport model. In the wave analysis component we consider refraction, diffraction and reflection based on Maruyama and Kajima method. For the wave-induced current model we use depth-integrated continuty equation and momentum equations. For the 3-dimensional sediment transport model we consider bed load and suspended load simutaneously. Model results obtained for Jin-ha Beach and Hyeya River mouth agreed well with experimental results.

  • PDF

A TWO-DIMENSIONAL CFD MODEL OF SMALL TURBOJET COMBUSTOR (소형 터보제트엔진 연소기의 2차원 전산유체해석 모델)

  • Lee, Se-Min;Park, Soo-Hyung;Lee, Chang-Jin;Lee, Dong-Hun;Paeng, Ki-Seok;Ryu, Jong-Hyeok;Ryu, Kyung-Won
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03a
    • /
    • pp.155-158
    • /
    • 2008
  • A practical modeling approach of a small slinger combustor is proposed and a 2-dimensional axisymmetric computational model is developed. Based on numerical results from the full 3-dimensional configuration, model reduction is achieved toward 2-dimensional axisymmetric configuration. By simplifying the complex model, computing time can be significantly reduced and it makes easy to find effects of geometry modification. Numerical results show that the flow characteristic of 2-D model is quite similar to that of the 3-D configuration.

  • PDF

Behavior of Gaseous Volatile Organic Compounds Considered by Density-Dependent Gas Advection (밀도차에 의해 발생하는 이송을 고려한 휘발성 유기화합물 가스의 거동)

  • 이창수;이영화
    • Journal of Environmental Science International
    • /
    • v.11 no.12
    • /
    • pp.1321-1326
    • /
    • 2002
  • A numerical model is investigated to predict a behavior of the gaseous volatile organic compounds and a subsurface contamination caused by them in the unsaturated zone. Two dimensional advective-dispersion equation caused by a density difference and two dimensional diffusion equation are computed by a finite difference method in the numerical model. A laboratory experiment is also carried out to compare the results of the numerical model. The dimensions of the experimental plume are 1.2m in length, 0.5m in height, and 0.05m in thickness. In comparing the result of 2 methods used in the numerical model with the one of the experiment respectively, the one of the advective-dispersion equation shows better than the one the diffusion equation.