Study on Testing Environment Simulation Method for Thermal Flux Density of Aerothermal

The separation technology in the large-scale sand-dust environment ground simulation test system applicable to the environmental adaptability and reliability verification of aerospace electromechanical products is studied. The gas-solid two-phase numerical simulation method is adopted, and the possible cyclone separation, inertial separation methods are used to study the separation efficiency and regularity technology, which provides a basis for the separation design and test of the sand-dust environment simulation of large electromechanical products.

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Simulation Study on the Force of Particles Migrating in Molten Metal under High-Frequency Magnetic Field

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1095.851 ◽

2015 ◽

Vol 1095 ◽

pp. 851-854

Author(s):

Hong Ming Wang ◽

Chang Chen Qu ◽

Xiao Jian Fan ◽

Gui Rong Li

Keyword(s):

Magnetic Flux ◽

Flux Density ◽

High Frequency ◽

Body Force ◽

Simulation Method ◽

Magnetic Flux Density ◽

Basic Principles ◽

Frequency Magnetic Field ◽

High Frequency Magnetic Field ◽

Magnetic Induction Intensity

According to the basic principles of electromagnetism, the magnetic flux density on the surface of the metal melt was calculated by numerical simulation method. The relational expression of the electromagnetic body force and the magnetic flux density was deduced. The results show that the electromagnetic body force in the melt is directly proportional to the square of the magnetic induction intensity. Increasing the electric current, the electromagnetic body force in the melt can be increased effectively. Increasing the frequency, the particular electromagnetic body force within the melt can be increased first and then decreased.

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EXPERIMENTAL DETERMINATION OF THE THERMAL FLUX DENSITY VARIATION LOST IN TIME BY A DIVER

ANNALS OF THE ORADEA UNIVERSITY Fascicle of Management and Technological Engineering ◽

10.15660/auofmte.2010-2.1906 ◽

2010 ◽

Vol XIX (IX), 2010/2 (2) ◽

Author(s):

CONSTANTIN Anca ◽

STANCIU Tamara

Keyword(s):

Experimental Determination ◽

Flux Density ◽

Thermal Flux ◽

Density Variation

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Field Distribution of Strongly Excited Magnetic Lenses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114323 ◽

1975 ◽

Vol 33 ◽

pp. 140-141

Author(s):

M. Strojnik

Keyword(s):

Flux Density ◽

Field Distribution ◽

Optical Axis ◽

Operating Point ◽

Pole Piece ◽

Partial Saturation ◽

Axial Flux ◽

The Stability

Magnetic lenses operating in partial saturation offer two advantages in HVEM: they exhibit small cs and cc and their power depends little on the excitation IN. Curve H, Fig. 1, shows that the maximal axial flux density Bz max of one of the lenses investigated changes between points (3) and (4) by 5% as the excitation varies by 40%. Consequently, the designer can relax the requirements concerning the stability of the lens current supplies. Saturated lenses, however, can only be used if (i) unwanted fields along the optical axis can be controlled, (ii) 'wobbling' of the optical axis due to inhomogeneous saturation around the pole piece faces is prevented, (iii) ample ampere-turns can be squeezed into the space available, and (iv) the lens operating point covers a sufficient range of accelerating voltages.

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The Added Value of Graphical Input and Display for Electron Lens Design

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100179701 ◽

1990 ◽

Vol 48 (1) ◽

pp. 190-191

Author(s):

B. Lencova ◽

G. Wisselink

Keyword(s):

Flux Density ◽

Numerical Data ◽

Added Value ◽

Lens Design ◽

Step Size ◽

Magnetic Lens ◽

Flux Lines ◽

Fine Mesh ◽

Electron Lens ◽

User Friendly

Recent progress in computer technology enables the calculation of lens fields and focal properties on commonly available computers such as IBM ATs. If we add to this the use of graphics, we greatly increase the applicability of design programs for electron lenses. Most programs for field computation are based on the finite element method (FEM). They are written in Fortran 77, so that they are easily transferred from PCs to larger machines.The design process has recently been made significantly more user friendly by adding input programs written in Turbo Pascal, which allows a flexible implementation of computer graphics. The input programs have not only menu driven input and modification of numerical data, but also graphics editing of the data. The input programs create files which are subsequently read by the Fortran programs. From the main menu of our magnetic lens design program, further options are chosen by using function keys or numbers. Some options (lens initialization and setting, fine mesh, current densities, etc.) open other menus where computation parameters can be set or numerical data can be entered with the help of a simple line editor. The "draw lens" option enables graphical editing of the mesh - see fig. I. The geometry of the electron lens is specified in terms of coordinates and indices of a coarse quadrilateral mesh. In this mesh, the fine mesh with smoothly changing step size is calculated by an automeshing procedure. The options shown in fig. 1 allow modification of the number of coarse mesh lines, change of coordinates of mesh points or lines, and specification of lens parts. Interactive and graphical modification of the fine mesh can be called from the fine mesh menu. Finally, the lens computation can be called. Our FEM program allows up to 8000 mesh points on an AT computer. Another menu allows the display of computed results stored in output files and graphical display of axial flux density, flux density in magnetic parts, and the flux lines in magnetic lenses - see fig. 2. A series of several lens excitations with user specified or default magnetization curves can be calculated and displayed in one session.

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Power of Modified Brown-Forsythe and Mixed-Model Approaches in Split-Plot Designs

Methodology ◽

10.1027/1614-2241/a000124 ◽

2017 ◽

Vol 13 (1) ◽

pp. 9-22 ◽

Cited By ~ 1

Author(s):

Pablo Livacic-Rojas ◽

Guillermo Vallejo ◽

Paula Fernández ◽

Ellián Tuero-Herrero

Keyword(s):

Repeated Measures ◽

Statistical Power ◽

Mixed Model ◽

Covariance Structure ◽

Simulation Method ◽

Future Research ◽

Repeated Measures Design ◽

Fixed And Random Effects ◽

Split Plot ◽

High Level

Abstract. Low precision of the inferences of data analyzed with univariate or multivariate models of the Analysis of Variance (ANOVA) in repeated-measures design is associated to the absence of normality distribution of data, nonspherical covariance structures and free variation of the variance and covariance, the lack of knowledge of the error structure underlying the data, and the wrong choice of covariance structure from different selectors. In this study, levels of statistical power presented the Modified Brown Forsythe (MBF) and two procedures with the Mixed-Model Approaches (the Akaike’s Criterion, the Correctly Identified Model [CIM]) are compared. The data were analyzed using Monte Carlo simulation method with the statistical package SAS 9.2, a split-plot design, and considering six manipulated variables. The results show that the procedures exhibit high statistical power levels for within and interactional effects, and moderate and low levels for the between-groups effects under the different conditions analyzed. For the latter, only the Modified Brown Forsythe shows high level of power mainly for groups with 30 cases and Unstructured (UN) and Autoregressive Heterogeneity (ARH) matrices. For this reason, we recommend using this procedure since it exhibits higher levels of power for all effects and does not require a matrix type that underlies the structure of the data. Future research needs to be done in order to compare the power with corrected selectors using single-level and multilevel designs for fixed and random effects.

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