Papers by Keyword: Electromagnetic Field (EMF)

Abstract: Electromagnetic stirring is an effective technique of improving the solidification structure and mechanical properties during continuous casting，because there is a notably effect of the flow on the density,segregation and inclusion of molten metal. In order to better understand the molten metal flow, the analysis software-ANSYS is used to simulate the 3D couple field of electromagnetic field and flow field for the self-developed rotating electromagnetic stirring equipment. The pure aluminum,tin and lead are used for both of experiment and simulation. The following results are obtained: 1) The magnetic induction intensity of liquid metal surface (B0) is in inversely proportional to the current frequency and is proportional to the input volt/current. 2) The maximum electromagnetic force is directly proportional to the square of magnetic induction intensity (B0) and the nth-power of current frequency decreases with the increase of the electric resistance of molten metal and changes from 1/2 to 3/2. The n is 1/2 for aluminum metal and 1 for tin metal and lead metal. 3) The rotating velocity of molten metal is directly proportional to the magnetic induction intensity(B0) and is in inversely proportional to the square root of the density of molten metal. The viscosity of molten metal has little effect on the rotating velocity. The above results are consistent with experiment results, which prove the credibility of simulate results.

Abstract: To analyze the variation of electromagnetic field distribution, a mathematical model of the eddy current brake (ECB) is established and the two-dimensional simulation and three-dimensional simulation are comparatively analyzed. Then the curves of the braking torque of the ECB at different speeds are obtained by the simulations. The characteristics of two-dimensional and three-dimensional simulation of the electromagnetic field of the ECB are summarized by contrasted comparative curves between simulation date and test date. The analysis is helpful to optimizing the application of electromagnetism by using software.

Abstract: The internal flow and level fluctuation of liquid metal exposed to linear electromagnetic stirring are mainly induced by the electromagnetic force. As a result, it is necessary to estimate the electromagnetic force amplitude generated by electromagnetic stirrers. The Maxwell's equations were simplified on some reasonable assumption so as to estimate the electromagnetic force amplitude in this study. During the electromagnetic force analysis, the characters of the electromagnetic force in liquid metal exposed to a linear electromagnetic stirrer were determined at the same time.

Abstract: In this paper, a static electromagnetic field problem will be solved. The method to solve the problem is Finite Difference Method ( FDM ). The software MATLAB is the main environment used to finish the numerical computing. Finally, we found using Finite Difference Method to solve a static electromagnetic field problem is quite convenient. We also can draw the two-dimension and three-dimension graph of the distribution of the electromagnetic field. Furthermore, we discuss the advantages of using FDM to solve the problem, and the disadvantages still exist in this method.

Abstract: In order to investigate the law of electromagnetic propagation within microwave heating system, Maxwell's equations are applied to build electromagnetic model of recycled asphalt mixtures. Energy distribution of electromagnetic field in asphalt mixtures is researched based on the Poynting theory. The optimization model of electromagnetic field and structure are established by building relationship between electric field and magnetic field. Experiments of microwave heating allochroic silicagel are performed, which demonstrates the accuracy of electromagnetic field optimization.

Abstract: This paper describes the various aspects of biological effects of high frequency electromagnetic fields on the human body. Specific Absorption Rate in human model by the IEC62209-1 standard is simulated and evaluated. Also the effect of change in physical parameter on Specific Absorption Rate is simulated and compared by IEC standard model. High Frequency Field Simulation Structure software has been used for simulations.

Abstract: The evolution of solidification structure in Incoloy800 with and without electromagnetic stirring (EMS) are studied to investigate its influence on the morphology of solidifying crystals and element segregation. The samples examination and EDX analysis show that some broken dendrite in the subsurface of the ingot were brought into the internal part of the ingot, it is proves the shear mechanism of EMS to dendrite or column crystal in the initial solidifying period, and the equiaxed grain region is formed in the internal part of ingots owing to the stirring effect of EMS. Both of them are helpful to reduce the element segregation in Incoly800 ingots.

Abstract: Abstract. For efficiently performing the numerical simulation of electromagnetic continues casting (EMCC) with finite element method (FEM) and finite volume method (FVM) combined scheme, a program integrates with data-format conversion and post-processing was proposed. The conversion of data format realized by linear interpolating, and the post processor developed on a Visual Fortran 6.6A platform using Fortran-95 language and the QuickWin module. Both 2-D and 3-D EM-FEM data calculated by a general-purpose FEM software, ANSYS, could be converted into FVM-data format using this program, and all FVM-data whether scalar quantities or vector ones could be displayed in the manners of cabinet drawing and normal axonometric drawing, which promises the correctness for data format conversion process of FEM/FVM-joint and the convenient analysis of transport phenomena during EMCC numerical simulation. The results of transport simulations and data format conversions indicate that the format-conversion method as well as the post processing is effective and convenient in numerical simulation with FEM/FVM-joint under various EM fields.

Abstract: The electro-magnetic field distribution and the effect of clearance ratio (CA) on magnetic flux leakage and the axial electro-magnetic force were analyzed and calculated by ANSYS. Through this method, we got the optimal value of clearance ratio, designed the axial magnetic bearing, and provided the theories and methods for the magnetic bearing’s analyzing and designing, which makes its designing faster and more conveniently.

Abstract: Low speed high torque direct drive motor has been widely applied in various industries. However, operation faults occur frequently due to the complex working conditions of the motor, especially the locked-rotor fault. Therefore, it is necessary to do deeply research in this case of the electromagnetic field and the temperature field distribution of the motor. Taking a 5kW, 10-pole tangential type Low speed high torque permanent magnet (PM) motor for example, based on field-circuit coupled finite element method, 2-D motor field, circuit and motion coupling is achieved. On this basis, the temperature field of the motor is analyzed. Finally the results which are consistent with the actual project are obtained.