Adaptive cell method with constitutive matrix correction for simulating physical field on a coarse grid

In this work, we have obtained a new constitutive matrix to calculate the induced Lorentz electric current of in a conductive disk in movement within a magnetic field using the cell method in 3D. This disk and a permanent magnet act as a magnetic brake. The results obtained are compared with those obtained with the finite element method (FEM) using the computer applications Getdp and femm. The error observed is less than 0.1173%. Likewise, a second verification has been made in the laboratory using Hall sensors to measure the magnetic field in the proximity of the magnetic brake.

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Thermal Analysis of a Magnetic Brake Using Infrared Techniques and 3D Cell Method with a New Convective Constitutive Matrix

Sensors ◽

10.3390/s19092028 ◽

2019 ◽

Vol 19 (9) ◽

pp. 2028 ◽

Cited By ~ 1

Author(s):

José Miguel Monzón-Verona ◽

Pablo Ignacio González-Domínguez ◽

Santiago García-Alonso ◽

Francisco Jorge Santana-Martín ◽

Juan Francisco Cárdenes-Martín

Keyword(s):

Magnetic Field ◽

Infrared Sensor ◽

The Finite Element Method ◽

Stationary Magnetic Field ◽

Infrared Sensors ◽

Cell Method ◽

Infrared Technology ◽

The Difference ◽

Constitutive Matrix ◽

Infrared Techniques

In this work we analyse the temperature distribution in a conductor disk in transitory regime. The disk is in motion in a stationary magnetic field generated by a permanent magnet and so, the electric currents induced inside it generate heat. The system acts as a magnetic brake and is analysed using infrared sensor techniques. In addition, for the simulation and analysis of the magnetic brake, a new thermal convective matrix for the 3D Cell Method (CM) is proposed. The results of the simulation have been verified by comparing the numerical results with those obtained by the Finite Element Method (FEM) and with experimental data obtained by infrared technology. The difference between the experimental results obtained by infrared sensors and those obtained in the simulations is less than 0.0459%.

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New Thermal-Conductivity Constitutive Matrix in Fourier’s Law for Heat Transfer Using the Cell Method

Applied Sciences ◽

10.3390/app9214521 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4521

Author(s):

González-Domínguez ◽

Monzón-Verona ◽

García-Alonso

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Finite Element Method ◽

Thermal Conduction ◽

Computational Method ◽

The Finite Element Method ◽

Cell Method ◽

Tetrahedral Meshes ◽

The Matrix ◽

Constitutive Matrix

In this paper, a new constitutive matrix Mτ for thermal conduction, for tetrahedral meshes, in a steady state thermal regime is developed through a new algebraic methodology, using the Cell Method as a computational method, which is included in the finite formulation. The constitutive matrix defines the behavior of solids when they are under a thermal potential. The results are compared with those obtained for the same problem by means of the constitutive matrix Mλ developed previously, taking in both cases with a 2D axisymmetric model as reference, calculated with the finite element method. The errors obtained with the new matrix Mτ are of the order of 0.0025%, much lower than those obtained with the matrix Mλ.

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Thermal constitutive matrix applied to asynchronous electrical machine using the cell method

Open Physics ◽

10.1515/phys-2018-0005 ◽

2018 ◽

Vol 16 (1) ◽

pp. 27-30 ◽

Cited By ~ 3

Author(s):

Pablo Ignacio González Domínguez ◽

José Miguel Monzón-Verona ◽

Leopoldo Simón Rodríguez ◽

Adrián de Pablo Sánchez

Keyword(s):

Heat Conduction ◽

Internal Heat ◽

Conduction Equation ◽

Equivalent Model ◽

Electrical Machine ◽

Heat Sources ◽

Conduction Model ◽

Cell Method ◽

Internal Heat Sources ◽

Constitutive Matrix

Abstract This work demonstrates the equivalence of two constitutive equations. One is used in Fourier’s law of the heat conduction equation, the other in electric conduction equation; both are based on the numerical Cell Method, using the Finite Formulation (FF-CM). A 3-D pure heat conduction model is proposed. The temperatures are in steady state and there are no internal heat sources. The obtained results are compared with an equivalent model developed using the Finite Elements Method (FEM). The particular case of 2-D was also studied. The errors produced are not significant at less than 0.2%. The number of nodes is the number of the unknowns and equations to resolve. There is no significant gain in precision with increasing density of the mesh.

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Transient thermal regime trough the constitutive matrix applied to asynchronous electrical machine using the cell method

Open Physics ◽

10.1515/phys-2018-0090 ◽

2018 ◽

Vol 16 (1) ◽

pp. 717-726 ◽

Cited By ~ 1

Author(s):

Pablo Ignacio González-Domínguez ◽

José Miguel Monzón-Verona ◽

Santiago García-Alonso

Keyword(s):

Thermal Regime ◽

Thermal Conduction ◽

Equation System ◽

Electrical Machine ◽

Cell Method ◽

Differential Formulation ◽

Transient Thermal ◽

Thermal Phenomena ◽

Physical Laws ◽

Constitutive Matrix

Abstract In this paper, a new constitutive matrix for thermal conduction in transient thermal regime is developed and tested. We use cell method as a numerical method that is included in finite formulation methodology. The constitutive matrix defines through the cell method the behavior of solids when they are under a thermal potential. We have demonstrated that this matrix is equivalent to the electrical conduction constitutive matrix in steady state. We have applied this constitutive matrix to thermal analysis of asynchronous electric machines in transient regime. This constitutive matrix has been validated with comparisons based on finite element method. In finite formulation, the physical laws governing the electromagnetic fields and the physical thermal phenomena are expressed in integral formulation. The final algebraic equation system is tailored directly without discretizing of the differential equations. This is an important advantage because we omit a complex differential formulation and the discretization of the respective equations.

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Computer programs for the calculation of x-ray intensities emitted by elements in multi-layer structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134685 ◽

1990 ◽

Vol 48 (2) ◽

pp. 216-217

Author(s):

G.F. Bastin ◽

H.J.M. Heijligers ◽

J.M. Dijkstra

Keyword(s):

Software Package ◽

Light Element ◽

Matrix Correction ◽

Excellent Performance ◽

Element Analysis ◽

X Ray ◽

Know How ◽

Accurate Knowledge ◽

Layer Structures ◽

Bulk Matrix

For the calculation of X-ray intensities emitted by elements present in multi-layer systems it is vital to have an accurate knowledge of the x-ray ionization vs. mass-depth (ϕ(ρz)) curves as a function of accelerating voltage and atomic number of films and substrate. Once this knowledge is available the way is open to the analysis of thin films in which both the thicknesses as well as the compositions can usually be determined simultaneously.Our bulk matrix correction “PROZA” with its proven excellent performance for a wide variety of applications (e.g., ultra-light element analysis, extremes in accelerating voltage) has been used as the basis for the development of the software package discussed here. The PROZA program is based on our own modifications of the surface-centred Gaussian ϕ(ρz) model, originally introduced by Packwood and Brown. For its extension towards thin film applications it is required to know how the 4 Gaussian parameters α, β, γ and ϕ(o) for each element in each of the films are affected by the film thickness and the presence of other layers and the substrate.

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