• 한국지하수토양환경학회지:지하수토양환경
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• 제27권spc호
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• pp.75-91
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• 2022

Differences in subsurface migration of LNAPL/DNAPL contaminants caused by a selection of 3-phase (aqueous, NAPL, and gas) relative permeability function (RPF) models in numerical modeling were investigated. Several types of RPF models developed from both experimental and theoretical backgrounds were introduced prior to conducting numerical modeling. Among the RPF models, two representative models (Stone I and Parker model) were employed to simulate subsurface LNAPLs/DNAPLs migration through numerical calculation. For each model, the spatiotemporal distribution of individual phases and the mole fractions of 6 NAPL components (4 LNAPL and 2 DNAPL components) were calculated through a multi-phase and multi-component numerical simulator. The simulation results indicated that both spilled LNAPLs and DNAPLs in the unsaturated zone migrated faster and reached the groundwater table sooner for Stone I model than Parker model while LNAPLs migrated faster on the groundwater table under Parker model. This results signified the crucial effect of 3-phase relative permeability on the prediction of NAPL contamination and suggested that RPF models should be carefully selected based on adequate verification processes for proper implementation of numerical models.

• 한국지하수토양환경학회지:지하수토양환경
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• 제6권1호
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• pp.45-52
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• 2001

토양 및 지하수의 오염문제가 심각해짐에 따라 오염물의 토양 및 지하수 내에서의 이동 특성에 관한 관심이 커지고 있다. 본 연구에서는 비용해성 흐름의 특성 및 그의 특성을 결정짓는 상대투수에 관한 기본적인 이해와 초음파가 상대투수에 미치는 영향에 관하여서도 고찰하였다. 실험 및 역해석의 결과로는 초음파가 오염물의 제거에 상당히 큰 영향을 끼치는 것으로 나타났으며 상대투수의 특성도 크게 변화되는 것으로 나타났다. 변화량은 $(C_{10})^2$의 함수로 나타낼 수 있었으며 ECLIPSE 100을 사용하여 초음파가 오염 복원 및 상대투수의 변화에 관한 연구에 활용 될 수 있음이 고찰되었다.

• Journal of Magnetics
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• 제22권1호
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• pp.93-99
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• 2017

The effort attempts to investigate the influence of various non-oriented electrical steel sheets on the core loss of a switched reluctance motor (SRM). The core loss of the motor inherits a strong correlation with flux density and permeability of the material. The study involves the use of laminated 2.7 % high silicon steel suitable for the motor in view of its higher flux density and lower core loss. The accurate prediction of core loss leaves way to suggest measures for improving the performance of the SRM. The dynamic simulation measurements of a 1.5 kW, three-phase 12/8 SRM involve the finite element method (FEM) and use the data obtained experimentally from Epstein frame. The closeness of the simulated and hardware results obtained with laminations of M400-50A, DI MAX-M19 and DI MAX-M15 both for the stator and rotor, espouse a greater significance to the findings in terms of the core loss density and forge new dimensions for its use in the drive industry.

• Geomechanics and Engineering
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• 제10권1호
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• pp.49-57
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• 2016

The high permeability-high strength concrete belongs to the typical of porous materials. It is mainly used in underground engineering for cold area, it can act the role of heat preservation, also to be the bailing and buffer layer. In order to establish a suitable model to predict the thermal conductivity and directly applied for engineering, according to the structure characteristics, the thermal conductivity predicting model was built by resistance network model of parallel three-phase medium. For the selected geometric and physical cell model, the thermal conductivity forecast model can be set up with aggregate particle size and mixture ratio directly. Comparing with the experimental data and classic model, the prediction model could reflect the mixture ratio intuitively. When the experimental and calculating data are contrasted, the value of experiment is slightly higher than predicting, and the average relative error is about 6.6%. If the material can be used in underground engineering instead by the commonly insulation material, it can achieve the basic requirements to be the heat insulation material as well.