Optimization of Axially Magnetized Stack Structured Permanent Magnet Thrust Bearing Using Three-Dimensional Mathematical Model

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Siddappa I. Bekinal ◽  
Mrityunjay Doddamani ◽  
Soumendu Jana

This work deals with optimization of axially magnetized stack structured permanent magnet (PM) thrust bearing using generalized three-dimensional (3D) mathematical model having “n” number of ring pairs. The stack structured PM thrust bearing is optimized for the maximum axial force and stiffness in a given cylindrical volume. matlab codes are written to solve the developed equations for optimization of geometrical parameters (axial offset, number of ring pairs, air gap, and inner radius of inner and outer rings). Further, the results of proposed optimization method are validated using finite element analysis (FEA) and further, generalized by establishing the relationship between optimal design variables and air gap pertaining to cylindrical volume constraint of bearing's outer diameter. Effectiveness of the proposed method is demonstrated by optimizing PM thrust bearing in a given cylindrical volume. Mathematical model with optimized geometrical parameters dealt in the present work helps the designer in developing PM thrust bearings effectively and efficiently for variety of applications.

Author(s):  
Siddappa Iranna Bekinal ◽  
Mrityunjay Doddamani ◽  
Mohan Vanarotti ◽  
Soumendu Jana

Optimization of rotational magnetized direction permanent magnet thrust bearing configuration is carried out using generalized three-dimensional mathematical model. The bearing features namely axial force and stiffness are maximized using in-house developed mathematical expressions solved using MATLAB. The design variables selected for the optimization are axial offset, number of ring pairs, air gap and inner radius of inner and outer rings. The maximized axial force values of the optimized configuration are validated with the finite element analysis results. To overcome the high computational cost associated with three-dimensional equations, generalized method of optimization is sucessfully demonstrated using plots representing variation of optimal design variables as a function of air gap with respect to bearing’s outer diameter. Simple and useful method of using the generalized plots for the process of optimization is presented by dimension optimization of representative bearing configuration with a particular aspect ratio. The proposed optimization using mathematical model and generalized approach assists designer in selecting optimized geometrical parameters of rotational magnetized direction thrust bearing configurations easily for variety of high-speed applications.


2016 ◽  
Vol 138 (3) ◽  
Author(s):  
Siddappa I. Bekinal ◽  
Soumendu Jana

This work deals with generalized three-dimensional (3D) mathematical model to estimate the force and stiffness in axially, radially, and perpendicularly polarized passive magnetic bearings with “n” number of permanent magnet (PM) ring pairs. Coulombian model and vector approach are used to derive generalized equations for force and stiffness. Bearing characteristics (in three possible standard configurations) of permanent magnet bearings (PMBs) are evaluated using matlab codes. Further, results of the model are validated with finite element analysis (FEA) results for five ring pairs. Developed matlab codes are further utilized to determine only the axial force and axial stiffness in three stacked PMB configurations by varying the number of rings. Finally, the correlation between the bearing characteristics (PMB with only one and multiple ring pairs) is proposed and discussed in detail. The proposed mathematical model might be useful for the selection of suitable configuration of PMB as well as its optimization for geometrical parameters for high-speed applications.


2011 ◽  
Vol 474-476 ◽  
pp. 1187-1190
Author(s):  
Qiang Song

Magnetic flux leakage (MFL) is a non-destructive testing method used to inspect the pipe and magnetization of the pipe wall to saturation is essential for anomalies to be reliably and accurately detected and characterized. Axial components of magnetic flux density obtained during the MFL inspection have been simulated using three-dimensional finite element analysis and the effects of magnetizing exciter parameters on magnetic flux density are investigated. The pipe modeled in this paper has an outer diameter of 127mm (5 in.) with a wall thickness of 9 mm (0.354 in.). According to numerical simulations, an increase in the magnetic flux density of pipe wall is observed with an increase in the permanent magnet length and height. It clearly illustrates that Nd-Fe-B permanent magnet assembly with 70 mm length and 40 mm height may magnetize pipe wall to near saturation.


Mathematics ◽  
2021 ◽  
Vol 9 (15) ◽  
pp. 1738
Author(s):  
Hina Usman ◽  
Junaid Ikram ◽  
Khurram Saleem Alimgeer ◽  
Muhammad Yousuf ◽  
Syed Sabir Hussain Bukhari ◽  
...  

In this paper, a hexagonal magnet shape is proposed to have an arc profile capable of reducing torque ripples resulting from cogging torque in a single-sided axial flux permanent magnet (AFPM) machine. The arc-shaped permanent magnet increases the air-gap length effectively and makes the flux of the air-gap more sinusoidal, which decreases air-gap flux density and hence causes a reduction in cogging torque. Cogging torque is the basic source of vibration, along with the noise in PM machines, since it is the main cause of torque ripples. Cogging torque is independent of the load current and is proportional to the air-gap flux and the reluctance variation. Three-dimensional finite element analysis (FEA) is used in the JMAG-Designer to analyze the performance of the conventional and proposed hexagonal-shaped PM AFPM machines. The proposed shape is designed to reduce cogging torque, and the voltage remains the same as compared to the conventional hexagonal-shaped PM machine. Further, optimization is performed by utilizing an asymmetric overhang. Latin hypercube sampling (LHS) is used to create samples, the kriging method is applied to approximate the model, and a genetic algorithm is applied to obtain the optimum parameters of the machine.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 1091-1101
Author(s):  
Zhihui Yang ◽  
Ren Liu ◽  
Bin Xia

Due to the large transverse edge effect for U-shaped ironless permanent magnet synchronous linear motor affect the distribution of air gap magnetic field is large, it will reduce the no-load back electromotive force and thrust. This paper proposes a novel method to evaluate the effect of transverse edge effect based on Kriging surrogate model. By comparing the results of the two-dimensional and three-dimensional finite element analysis of the air gap magnetic field of the motor, it can be seen transverse length of the motor, air gap height and thickness of the permanent magnet are the main influencing factors.


Author(s):  
Y. Oner ◽  
Z.Q. Zhu ◽  
L.J. Wu ◽  
X. Ge

Purpose – Due to high electromagnetic torque at low speed, vernier machines are suitable for direct-drive applications such as electric vehicles and wind power generators. The purpose of this paper is to present an exact sub-domain model for analytically predicting the open-circuit magnetic field of permanent magnet vernier machine (PMVM) including tooth tips. The entire field domain is divided into five regions, viz. magnets, air gap, slot openings, slots, and flux-modulation pole slots (FMPs). The model accounts for the influence of interaction between PMs, FMPs and slots, and radial/parallel magnetization. Design/methodology/approach – Magnetic field distributions for slot and air-gap, flux linkage, back-EMF and cogging torque waveforms are obtained from the analytical method and validated by finite element analysis (FEA). Findings – It is found that the developed sub-domain model including tooth tips is very accurate and is applicable to PMVM having any combination of slots/FMPs/PMs. Originality/value – The main contributions include: accurate sub-domain model for PMVM is proposed for open-circuit including tooth-tip which cannot be accounted for in literature; the model accounts the interaction between flux modulation pole (FMP) and slot; developed sub-domain model is accurate and applicable to any slot/FMP/PM combinations; and it has investigated the influence of FMP/slot opening width/height on cogging torque.


2019 ◽  
Vol 28 ◽  
pp. 01020
Author(s):  
Łukasz Knypiński

The paper presents an algorithm and computer software for the optimization of electromagnetic devices. The mathematical model of the optimization method was presented. The modification of the classical grey wolf algorithm was developed. The modification consists in decreasing the coefficient responsible for the possibility of migration individuals in the permissible area of solved task. The optimization procedure was elaborated in the Borland Delphi environment. The optimization of the rotor of the line-start permanent magnet synchronous motor has been carried out. It has been pointed out that the grey wolf algorithm is effective method for optimization of electromagnetic devices.


Symmetry ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1837 ◽  
Author(s):  
Martin Sotola ◽  
David Stareczek ◽  
David Rybansky ◽  
Jiri Prokop ◽  
Pavel Marsalek

This paper presents a new design procedure for production of a transtibial prosthesis bed stump by three-dimensional (3D) printing with topological optimization. The suggested procedure combines the medical perspective with finite element analysis and facilitates regaining the symmetry in patients with transtibial prosthesis, which leads to life improvement. The particular focus of the study is the weight reduction of the lower part of the bed stump, while taking into account its stiffness and load-bearing capacity. The first part of the work deals with the analysis of the subject geometry of the bed stump, which is usually oversized in terms of the weight and stiffness that are necessary for the current application. In the second part, an analysis of walking biomechanics with a focus on the impact and rebound phases is presented. Based on the obtained information, a spatial model of the lower part of the bed stump is proposed in the third phase, in which the finite element method is described. In the fourth part, the topological optimization method is used for reducing the structure weight. In the last part, the results of the designed model are analyzed. Finally, the recommendations for the settings of the method are presented. The work is based on the practical industry requirements, and the obtained results will be reflected in the design of new types of transtibial prosthesis.


Author(s):  
L. Goteti ◽  
J. Choi ◽  
J. Park

Snap-fit integral attachments are used widely for joining plastic parts. The proliferated use of integral attachment in the form of snap-fit features in designs is due to the ability to mould such parts of great complexity at little cost. The exceptional diversity of part geometry and integral snap-fit features has made it seem that design possibilities may be unlimited. Thus, attempts at optimization might be intractable. A design of experiments (DOE) approach coupled with three-dimensional, geometrical non-linear finite element analysis (FEA) was used to calculate the insertion and retention responses on such parts for various geometrical parameters like length, width and angles. A statistical technique was employed to formulate empirical relationships among the geometrical dimensions, to investigate the effect of these parameters on the design as well as to obtain optimal insertion and retention forces or strains. Design equations obtained from this methodology were verified within the DOE domain and it was observed that the predicted responses were ranged within 30% of the FEA results. During this investigation, it was observed that geometrical features of a block, which exert force on the snap-fit features, have a considerable effect on the results. Therefore, the effects of the block parameters on the various responses were also studied. An attempt was also made to understand the effect of the block parameters such as corner radius and thickness on the design formula, which depicts the geometrical parameters of the snap-fit part as a function of insertion and retention forces. It is expected that the results help to find optimal design parameters in order to enhance the performance of such snap-fit features.


2020 ◽  
Vol 8 (1) ◽  
pp. 29-46
Author(s):  
S. Rakshe ◽  
S. V. Nimje ◽  
S. K. Panigrahi

A review on optimization of adhesively bonded spar-wingskin joint (SWJ) of laminated fiber reinforced polymer (FRP) composites subjected to pull-off load is presented in this article using three-dimensional finite element analysis. Von Mises stress components have been computed across the width of joint at different interfaces viz. load coupler-spar, and load coupler-wingskin interfaces. Further, the weight of SWJ structure is considered as the objective function which needs to be minimized for optimization. In the first step, the material and lamination scheme of the FRP composite materials used for SWJ are optimized, and, in the second step, the geometrical parameters have been optimized on the basis of minimum von Mises stress and weight. Further, the effects of the material, lamination scheme, and geometrical parameters on the von Mises stress and weight have been validated using the Analysis of Variance (ANOVA) approach as prescribed by the Taguchi method. The results show that the material and spar thickness are the most significant factors influencing von Mises stress. The weight analysis reveals that there is a significant effect of change in material and wingskin thickness on SWJ performance. Suitable design recommendations have been made for SWJ in terms of material, lamination scheme and geometrical parameters.


Sign in / Sign up

Export Citation Format

Share Document