Design of a numerical model of lung by means of a special boundary condition in the truncated branches

2016 ◽  
Vol 33 (6) ◽  
pp. e2830 ◽  
Author(s):  
Ana F. Tena ◽  
Joaquín Fernández ◽  
Eduardo Álvarez ◽  
Pere Casan ◽  
D. Keith Walters
Keyword(s):  
Boundary Condition ◽  
Numerical Model ◽  
Special Boundary ◽  
Special Boundary Condition

Ermittlung der magnetischen Widerstandsänderung und der HALL-Spannung mittels eines Widerstandsnetzwerkes

1963 ◽  
Vol 18 (1) ◽  
pp. 44-51 ◽  
Author(s):  
C. B. Burckhardt ◽  
M. J. O. Strutt
Keyword(s):  
Magnetic Field ◽  
Boundary Condition ◽  
Boundary Value Problem ◽  
Iterative Process ◽  
Boundary Value ◽  
Special Method ◽  
Special Boundary ◽  
Free Boundaries ◽  
Special Boundary Condition ◽  
The Magnetic Field

The potential of a semiconductor slab in a magnetic field satisfies LAPLACE'S equation ΔV= 0. The magnetic field causes a special boundary condition at the free boundaries. It is shown how this boundary value problem is solved by means of a resistance-network and feeding currents. For obtaining stability of the iterative process the feeding currents have to be calculated by a special method. The accuracy of the solutions obtained is good, as comparison with calculation (square slab) and measurements (square gyrator) shows. Further possibilities of application are suggested.

scholarly journals Experimental and Theoretical Research on Bending Behavior of Photovoltaic Panels with a Special Boundary Condition

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3435 ◽  
Author(s):  
Tengyuan Zhang ◽  
Lingzhi Xie ◽  
Yongxue Li ◽  
Tapas Mallick ◽  
Qingzhu Wei ◽  
...  
Keyword(s):  
Boundary Condition ◽  
Closed Form Solution ◽  
Form Solution ◽  
Theoretical Research ◽  
Systematic Research ◽  
Special Boundary ◽  
Governing Equations ◽  
Simply Supported ◽  
Special Boundary Condition ◽  
Bending Behavior

Currently, the photovoltaic (PV) panels widely manufactured on market are composed of stiff front and back layers and the solar cells embedded in a soft polymeric interlayer. The wind and snow pressure are the usual loads to which working PV panels need to face, and it needs the panels keep undamaged under those pressure when they generate electricity. Therefore, an accurate and systematic research on bending behavior of PV panels is important and necessary. In this paper, classical lamination theory (CLT) considering soft interlayer is applied to build governing equations of the solar panel. A Rayleigh–Rita method is modified to solve the governing equations and calculate the static deformation of the PV panel. Different from many previous researches only analyzing simply supported boundary condition for four edges, a special boundary condition which consists of two opposite edges simply supported and the others two free is studied in this paper. A closed form solution is derived out and used to do the numerical calculation. The corresponding bending experiments of PV panels are completed. Comparing the numerical results with experiment results, the accuracy of the analytical solutions are verified.

scholarly journals Discrete-to-continuum limits of planar disclinations

2021 ◽  
Vol 27 ◽  
pp. 23
Author(s):  
Pierluigi Cesana ◽  
Patrick van Meurs
Keyword(s):  
Boundary Condition ◽  
Nearest Neighbor ◽  
Materials Science ◽  
Additional Term ◽  
Density Theorem ◽  
Special Boundary ◽  
Relaxation Methods ◽  
Planar Domains ◽  
Special Boundary Condition ◽  
Numerical Minimization

In materials science, wedge disclinations are defects caused by angular mismatches in the crystallographic lattice. To describe such disclinations, we introduce an atomistic model in planar domains. This model is given by a nearest-neighbor-type energy for the atomic bonds with an additional term to penalize change in volume. We enforce the appearance of disclinations by means of a special boundary condition. Our main result is the discrete-to-continuum limit of this energy as the lattice size tends to zero. Our proof relies on energy relaxation methods. The main mathematical novelty of our proof is a density theorem for the special boundary condition. In addition to our limit theorem, we construct examples of planar disclinations as solutions to numerical minimization of the model and show that classical results for wedge disclinations are recovered by our analysis.

scholarly journals NUMERICAL SIMULATION OF 1964 TSUNAMI ACROSS THE PACIFIC OCEAN

1986 ◽  
Vol 1 (20) ◽  
pp. 5
Author(s):  
Michael H. Chen
Keyword(s):  
Numerical Simulation ◽  
Boundary Condition ◽  
Numerical Model ◽  
Pacific Ocean ◽  
Arrival Time ◽  
Two Dimensional ◽  
Open Sea ◽  
The Pacific ◽  
The Pacific Ocean

A two dimensional numerical longwave model using an appropriate open sea boundary condition has been developed. The use of the open-sea boundary condition makes it possible to simulate longwave propagation using a smaller region without covering the entire ocean. The numerical model is used to predict the arrival time of tsunamis resulting from the 1964 Alaskan earthquake at various stations with reasonable success.

scholarly journals Experimental and numerical analysis of soil desiccating cracks in compacted and non-compacted specimens

2020 ◽  
Vol 195 ◽  
pp. 03021
Author(s):  
Josbel Cordero ◽  
Abdallah Najdi ◽  
David Encalada ◽  
Pere C. Prat ◽  
Alberto Ledesma
Keyword(s):  
Boundary Condition ◽  
Porous Medium ◽  
Numerical Model ◽  
Unsaturated Flow ◽  
The Other ◽  
Silty Clay ◽  
Balance Equations ◽  
Transfer Coefficients ◽  
Photographic Images ◽  
Gravimetric Water Content

This paper presents the results and analysis of two cracking tests carried on specimens of silty clay. One specimen was prepared in slurry conditions without applying energy and the other specimen was compacted. They were dried in an environmental chamber at a constant temperature and relative humidity to study the effect of the initial consistency on the cracking behaviour. Weight measurements and photographic images taken at regular intervals documented the evolution of the specimens. THM models were then carried to capture the unsaturated flow in the porous medium due to evaporation, and its resulting shrinkage. All the numerical analyses were coupled, incorporating the effect of porosity change on the balance equations and the constitutive model. The transfer coefficients in the imposed drying boundary condition were based on calculations of aerodynamic surface resistances, taking into consideration the new fronts for evaporation created by the cracks. The constructed numerical model results capture the gravimetric water content loss and the occurring shrinkage for both specimen conditions.

scholarly journals Improving Water Level Forecast of an Oceanographic Model in Malacca Strait Based on Data-Driven Open Boundary Correction

10.29007/9bfr ◽  
2018 ◽  
Author(s):  
Xuan Wang ◽  
Serene Hui Xin Tay ◽  
Vladan Babovic
Keyword(s):  
Boundary Condition ◽  
Numerical Model ◽  
Open Boundary ◽  
Computational Domain ◽  
Time Step ◽  
Underlying Assumption ◽  
Indispensable Tool ◽  
Data Assimilation Technique ◽  
Oceanographic Model ◽  
Boundary Correction

Numerical model is an indispensable tool for understanding oceanographic phenomena and resolving associated physical processes. However, model error cannot be avoided due to limitations such as underlying assumption, insufficient information of bathymetry or boundary condition and so on. Data assimilation technique thus becomes an effective and essential tool to improve prediction accuracy. Updating of output is an efficient way to correct the model, but it is often carried out locally at specific locations in the model domain where measurement is available. In this study, instead of correcting output of numerical model locally, we propose to combine local correction and input correction to update open boundary of numerical model. The open boundary condition is corrected through spatial interpolation algorithm based on nearby observation in the hindcast period. Then the local forecast at measured location is distributed using the same interpolation scheme to update the boundary in the forecast period. Such boundary correction not only explores the variation in the future time step from the input updating but also allows the backbone physics embedded in numerical model to resolve the hydrodynamics in the entire computational domain.

scholarly journals 3D numerical modeling of flow and sediment transport in rivers and open channels

2019 ◽  
Vol 3 (1) ◽  
pp. 23-36
Author(s):  
Le Song Giang ◽  
Tran Thi My Hong
Keyword(s):  
Boundary Condition ◽  
Sediment Transport ◽  
Numerical Model ◽  
Differential Equations ◽  
Water Level ◽  
Suspended Sediment ◽  
Three Dimensional ◽  
River Bed ◽  
Suspended Sediment Concentrations ◽  
Flow And Sediment Transport

Numerical model is a useful tool in studying the flow and sediment transport, change in river bed and is built on solving governing differential equations. Numerical model has many different levels and three-dimensional model is the highest level, allowing detailed simulation of flow and sediment transport process in 3D space. The paper presents a method calculating three - dimensional flow and sediment transport in the open channel. Water level and flow velocity are solved from three-dimensional equations with hydrostatic hypothesis. Concentration of suspended sediment, bottom sediment and bottom evolution is solved from transport equations. The governing differential equations in the "sigma" transform coordinate system are solved by finite volume method on unstructured grid of quadrilateral elements. Boundary condition of water level or flow will be imposed on open boundary. For suspended sediment concentrations in the injected phase, suspended sediment concentrations are applied and the outflow phase applies free drainage conditions. This method of calculation was tested with the problem of curved channel sediment transport which was studied experimentally by Odgaard and Bergs. Calculation results are quite consistent with the measured data. In order to test the practical applicability, this method is also tested with the problem of sediment transport in Cu lao Pho islet on Dong Nai river. To solve the matter of hydraulic boundary condition of this problem, the model of Cu lao Pho islet is integrated into the Sai Gon - Dong Nai river system model. Results of the calculation of the river bed evolution of the Cu lao Pho islet on the Dong Nai river also show that this calculation method gives results consistent with the rule and can be used in practical research.  

Sign in / Sign up

Export Citation Format

Share Document