A one-step leapfrog HIE-FDTD method for rotationally symmetric structures

2016 ◽  
Vol 27 (4) ◽  
pp. e21081 ◽  
Author(s):  
Da-Wei Zhu ◽  
Yi-Gang Wang ◽  
Hai-Lin Chen ◽  
Bin Chen
Keyword(s):  
Fdtd Method ◽  
Rotationally Symmetric ◽  
One Step ◽  
Symmetric Structures

Q-BOR–FDTD method for solving Schrodinger equation for rotationally symmetric nanostructures with hydrogenic impurity

2022 ◽  
Author(s):  
Arezoo Firoozi ◽  
Ahmad Mohammadi ◽  
Reza Khordad ◽  
Tahmineh Jalali
Keyword(s):  
Schrödinger Equation ◽  
Analytical Solutions ◽  
Schrodinger Equation ◽  
Fdtd Method ◽  
Three Dimensional ◽  
Test Cases ◽  
Body Of Revolution ◽  
Hydrogenic Impurity ◽  
Rotationally Symmetric ◽  
Difference Time

Abstract An efficient method inspired by the traditional body of revolution finite-difference time-domain (BOR-FDTD) method is developed to solve the Schrodinger equation for rotationally symmetric problems. As test cases, spherical, cylindrical, cone-like quantum dots, harmonic oscillator, and spherical quantum dot with hydrogenic impurity are investigated to check the efficiency of the proposed method which we coin as Quantum BOR-FDTD (Q-BOR-FDTD) method. The obtained results are analysed and compared to the 3-D FDTD method, and the analytical solutions. Q-BOR-FDTD method proves to be very accurate and time and memory efficient by reducing a three-dimensional problem to a two-dimensional one, therefore one can employ very fine meshes to get very precise results. Moreover, it can be exploited to solve problems including hydrogenic impurities which is not an easy task in the traditional FDTD calculation due to singularity problem. To demonstrate its accuracy, we consider spherical and cone-like core-shell QD with hydrogenic impurity. Comparison with analytical solutions confirms that Q-BOR–FDTD method is very efficient and accurate for solving Schrodinger equation for problems with hydrogenic impurity

Tailored heating of forging billets using induction and conduction heating approaches

2019 ◽  
Vol 39 (1) ◽  
pp. 100-107
Author(s):  
Martin Schulze ◽  
Egbert Baake
Keyword(s):  
Heating Process ◽  
Content Type ◽  
Rotationally Symmetric ◽  
First Results ◽  
Thermal Solution ◽  
One Step ◽  
Transient Thermal ◽  
Method Model ◽  
Practical Implications ◽  
Conduction Heating

Purpose This paper aims to deal with different induction and conduction heating approaches to realize a tailored heating of round billets for hot forming processes. In particular, this work examines the limits in which tailor-made temperature profiles can be achieved in the billet. In this way, a flow stress distribution based on the temperature field in the material can be set in a targeted manner, which is decisive for forming processes. Design/methodology/approach For the heating of round billets by induction, the rotationally symmetric arrangement is used and a parameterized 2D finite element method model is created. The harmonic electromagnetic solution is coupled with the transient thermal solution. For heating by means of conduction, the same procedure is used only with the use of a 3D model. Findings First results have shown that both methods can achieve very good results for billets with small diameters (d < 30 mm). For larger diameters, an adapted control of the heating process is necessary to ensure through heating of the material. Further investigations are carried out. Practical implications Using tailored heating for forging billets, several forming steps can be achieved in one step. Among other things, higher energy efficiency and throughput rates can be achieved. Originality/value The peculiarity of the tailored heating approach is that, in contrast to inhomogeneous heating, where only partial areas are heated, the entire component is heated to the target.

The Unconditionally Stable One-Step Leapfrog ADI-FDTD Method and Its Comparisons With Other FDTD Methods

2011 ◽  
Vol 21 (12) ◽  
pp. 640-642 ◽  
Author(s):  
Shun-Chuan Yang ◽  
Zhizhang David Chen ◽  
Yi-qiang Yu ◽  
Wen-Yan Yin
Keyword(s):  
Fdtd Method ◽  
Unconditionally Stable ◽  
One Step ◽  
Fdtd Methods

An Optimized One-Step Leapfrog HIE-FDTD Method With the Artificial Anisotropy Parameters

2020 ◽  
Vol 68 (2) ◽  
pp. 1198-1203 ◽  
Author(s):  
Yong-Dan Kong ◽  
Chu-Bin Zhang ◽  
Qing-Xin Chu
Keyword(s):  
Fdtd Method ◽  
One Step ◽  
Anisotropy Parameters

ONE-STEP LEAPFROG HIE-FDTD METHOD FOR LOSSY MEDIA

2015 ◽  
Vol 54 ◽  
pp. 21-26 ◽  
Author(s):  
Jian-Yun Gao ◽  
Xiang-Hua Wang ◽  
Hong-Xing Zheng
Keyword(s):  
Fdtd Method ◽  
One Step ◽  
Lossy Media

One-Step Leapfrog ADI-FDTD Method Including Lumped Elements and Its Stability Analysis

2012 ◽  
Vol 11 ◽  
pp. 1406-1409 ◽  
Author(s):  
Xiang-Hua Wang ◽  
Wen-Yan Yin ◽  
Zhizhang Chen ◽  
Shun-Chuan Yang
Keyword(s):  
Stability Analysis ◽  
Fdtd Method ◽  
Lumped Elements ◽  
One Step

Review of Lower-Bound Limit Analysis for Pressure Vessel Intersections

1977 ◽  
Vol 99 (3) ◽  
pp. 413-418 ◽  
Author(s):  
A. Biron
Keyword(s):  
Lower Bound ◽  
Lower Bounds ◽  
Limit Analysis ◽  
Pressure Vessel ◽  
General Purpose ◽  
Collapse Load ◽  
Rotationally Symmetric ◽  
Bound Theorem ◽  
Symmetric Structures ◽  
Lower Bound Limit Analysis

On the basis of a study of several recent papers concerned with the lower-bound computation of the collapse load of pressure vessel intersections, a review is made of the satisfaction, or nonsatisfaction, of the requirements of the lower-bound theorem of limit analysis. It is shown that, whereas for rotationally symmetric structures true lower bounds have been obtained, for a nonsymmetric case such as a right cylinder-cylinder intersection it is difficult to avoid so me approximations. If attempts are to be made to develop general purpose limit analysis programs, the consequences of approximations of the type used so far must be evaluated with care if significant results are to be obtained.

scholarly journals Implementation of CPML for One-Step Leapfrog WCS-FDTD Method

2015 ◽  
Vol 25 (8) ◽  
pp. 496-498 ◽  
Author(s):  
Xiang-Hua Wang ◽  
Wen-Yan Yin ◽  
Zhizhang Chen
Keyword(s):  
Fdtd Method ◽  
One Step
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