The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform

Baolin Wang - One of the best experts on this subject based on the ideXlab platform.

  • Exact and Fundamental Solution for an Anti-plane Crack Vertical to the Boundaries of a Magnetoelectroelastic Strip:
    International Journal of Damage Mechanics, 2020
    Co-Authors: Baolin Wang
    Abstract:

    In this article, we develop a closed-form solution for a crack in a magnetoelectroelastic strip of finite width, subjected to anti-plane mechanical and in-plane electric and magnetic fields. Explicit expressions for the stresses, electric and magnetic fields, together with their intensity factors are obtained for the two extreme cases of an impermeable crack and a permeable crack. Solutions for some special cases, such as a center crack, an edge crack, a semi-infinite medium, and an infinite medium, are also obtained in closed-forms. The problem of two symmetric and collinear cracks is also discussed. It is found that the electrically and magnetically permeable Conditions on the crack profile are important in obtaining the correct crack tip Electromagnetic filed intensity factors. The stress intensity factor, however, does not depend on the crack Electromagnetic Boundary Condition assumptions.

  • Multiple cracking of magnetoelectroelastic materials in coupling thermo–electro–magneto-mechanical loading environments
    Computational Materials Science, 2007
    Co-Authors: Baolin Wang
    Abstract:

    Abstract Magnetoelectroelastic materials are inherently brittle and prone to fracture. Therefore, it is important to model evaluate the fracture behavior of these advanced materials. In this paper, a periodic array of cracks in a magnetoelectroelastic material is investigated. The problem is solved by integral transform and integral equation technique. Impermeable and permeable crack-face Electromagnetic Boundary Condition assumptions are studied. The stress, electric displacement and magnetic induction and their intensity factors are obtained. Effect of the crack spacing on these quantities is investigated in details. The problem of transient fracture by a transient temperature variation along the crack lines is also investigated. Parameters governing the transient thermo–electro–magneto-elastic fields are identified.

  • applicability of the crack face Electromagnetic Boundary Conditions for fracture of magnetoelectroelastic materials
    International Journal of Solids and Structures, 2007
    Co-Authors: Baolin Wang
    Abstract:

    This paper discusses the different Electromagnetic Boundary Conditions on the crack-faces in magnetoelectroelastic materials, which possess coupled piezoelectric, piezomagnetic and magnetoelectric effects. A notch of finite thickness in these materials containing air (or vacuum) is also addressed. Four ideal crack-face Electromagnetic Boundary Condition assumptions, that is, (a) electrically and magnetically impermeable crack, (b) electrically impermeable and magnetically permeable crack, (c) electrically permeable and magnetically impermeable crack and (d) electrically and magnetically permeable crack, are investigated separately. The influence of notch thickness on the field intensity factors at notch tips and the Electromagnetic field inside the notch are obtained in closed-form. The results are compared with the ideal crack solutions. Applicability of crack-face Electromagnetic Boundary Condition assumptions is discussed.

  • mode iii fracture of a magnetoelectroelastic layer exact solution and discussion of the crack face Electromagnetic Boundary Conditions
    International Journal of Fracture, 2006
    Co-Authors: Baolin Wang
    Abstract:

    This paper develops a closed-form solution for anti-plane mechanical and in plane electric and magnetic fields in a magnetoelectroelastic layer of finite thickness. Explicit expressions for the stresses, electric fields, and magnetic fields, together with their intensity factors are obtained for the extreme cases for impermeable and permeable cracks. Solutions for some special cases, such as a magnetoelectroelastic layer with infinite thickness, are also obtained. Applicability of the crack face Electromagnetic Boundary Conditions is discussed. It is found that the crack profile is important in obtaining the correct Electromagnetic fields and their intensity factors. The stress intensity factor, however, does not depend on the crack face Electromagnetic Boundary Condition assumptions.

Mingtian Xu - One of the best experts on this subject based on the ideXlab platform.

  • effect of Electromagnetic Boundary Condition on dynamo actions
    Science China-physics Mechanics & Astronomy, 2015
    Co-Authors: Mingtian Xu
    Abstract:

    In this paper, based on the mean field dynamo theory, the influence of the Electromagnetic Boundary Condition on the dynamo actions driven by the small scale turbulent flows in a cylindrical vessel is investigated by the integral equation approach. The numerical results show that the increase of the electrical conductivity or magnetic permeability of the walls of the cylindrical vessel can reduce the critical magnetic Reynolds number. Furthermore, the critical magnetic Reynolds number is more sensitive to the varying electrical conductivity of the end wall or magnetic permeability of the side wall. For the anisotropic dynamo which is the mean field model of the Karlsruhe experiment, when the relative electrical conductivity of the side wall or the relative magnetic permeability of the end wall is less than some critical value, the m=1 (m is the azimuthal wave number) magnetic mode is the dominant mode, otherwise the m=0 mode predominates the excited magnetic field. Therefore, by changing the material of the walls of the cylindrical vessel, one can select the magnetic mode excited by the anisotropic dynamo.

J.m. Jarem - One of the best experts on this subject based on the ideXlab platform.

  • A multipole analysis of a dielectric loaded coaxial rectangular waveguide
    IEEE Transactions on Microwave Theory and Techniques, 1992
    Co-Authors: M.z. Mohamed, J.m. Jarem
    Abstract:

    A multipole analysis of a coaxial rectangular waveguide whose inner conductor is circular is made in order to determine the TE and TM modes of the system. The analysis is based on using multipole (dipole, quadrupole etc.) electric and magnetic current sources to generate field solutions in the waveguide. These solutions are used to match the Electromagnetic Boundary Condition in a homogeneous coaxial rectangular waveguide and to determine the TE and TM eigenvalues of the waveguide system. Eigenvalue results are compared with results of the generalized spectral domain method and to eigenvalue results for a ridged waveguide. Propagation in a coaxial rectangular waveguide is also studied when the coaxial rectangular waveguide is loaded with lossy inhomogeneous dielectric material. A variational formula is used to relate the TEM, TE, and TM modes of an empty coaxial rectangular waveguide to the propagation in the loaded inhomogeneous dielectric waveguide.

M.z. Mohamed - One of the best experts on this subject based on the ideXlab platform.

  • A multipole analysis of a dielectric loaded coaxial rectangular waveguide
    IEEE Transactions on Microwave Theory and Techniques, 1992
    Co-Authors: M.z. Mohamed, J.m. Jarem
    Abstract:

    A multipole analysis of a coaxial rectangular waveguide whose inner conductor is circular is made in order to determine the TE and TM modes of the system. The analysis is based on using multipole (dipole, quadrupole etc.) electric and magnetic current sources to generate field solutions in the waveguide. These solutions are used to match the Electromagnetic Boundary Condition in a homogeneous coaxial rectangular waveguide and to determine the TE and TM eigenvalues of the waveguide system. Eigenvalue results are compared with results of the generalized spectral domain method and to eigenvalue results for a ridged waveguide. Propagation in a coaxial rectangular waveguide is also studied when the coaxial rectangular waveguide is loaded with lossy inhomogeneous dielectric material. A variational formula is used to relate the TEM, TE, and TM modes of an empty coaxial rectangular waveguide to the propagation in the loaded inhomogeneous dielectric waveguide.

Huang Kama - One of the best experts on this subject based on the ideXlab platform.

  • Integrated design for microwave radiator used in microwave chemical reactor
    CIESC Journal, 2020
    Co-Authors: Huang Kama
    Abstract:

    An integrated design and optimization method of the microwave radiator used in a microwave chemical reactor is discussed.The radiator,made of high-borosilicate glass,is an important part of the reactor,by which the microwave energy is delivered from the microwave source to the cavity of the reactor.It is composed of radiating part,baffle and impedance matching part,to obtain better radiating effect.However,under the influence of the microwave energy,the thermal stress,resulted from the large variation of temperature when the reactor is working,may make the radiator crack,so that the reactor does not work properly,even leading to explosion.In order to avoid the above phenomenon,the design of reactor is modified.First,based on the analysis on the Electromagnetic transmission characteristics of the radiator,in which the Maxwell equations are solved with the Electromagnetic Boundary Condition by finite-element method,the structural parameters of the radiator is optimized,to make the reflection coefficient as low as possible to reduce the loss of microwave energy during the transmission.Secondly,the design of radiator is modified to improve its stability to avoid the excessive local thermal stress at the transition structure,in which the integrated analysis for multi-fields is applied by solving the Maxwell equations,the heat conduction equation and the thermoelastic equation.The desired results are obtained.The reflection coefficient is below-10 dB,as required,in the frequency range of 2.4—2.5 GHz,the thermal stress is reduced greatly from 17.62 MPa to 12.43 MPa,and the position with the highest thermal stress is away from the joint of the baffle and the radiating part,so that the radiator is more stable during the operation.This method can be applied to develop microwave radiators with good stability,and it is of practical value in the industrial production.