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Article
Publication date: 11 October 2020

Muhammad Umair, Faisal Khan and Wasiq Ullah

Field excited flux switching machines (FEFSM) are preferred over induction and synchronous machines due to the confinement of all excitation sources on the stator leaving…

Abstract

Purpose

Field excited flux switching machines (FEFSM) are preferred over induction and synchronous machines due to the confinement of all excitation sources on the stator leaving a robust rotor. This paper aims to perform coupled electromagnetic thermal analysis and stress analysis for single phase FEFSM as, prolonged high-speed operational time with core and copper losses makes it prone to stress and thermal constraints as temperature rise in machine lead to degraded electromagnetic performance whereas the violation of the principle stress limit may result in mechanical deformation of the rotor.

Design/methodology/approach

This paper presents the implementation of coupled electromagnetic-thermal and rotor stress analysis on single-phase FEFSM with non-overlap winding configurations using finite element analysis (FEA) methodology in JMAG V. 18.1. three-dimensional (3D) magnetic loss analysis is performed and extended to 3D thermal analysis to predict temperature distribution on various parts of the machine whereas Stress analysis predicts mechanical stress acting upon edges and faces of the rotor.

Findings

Analysis reveals that temperature distribution and rotor stress on the machine is within acceptable limits. A maximum temperature rise of 37.7°C was noticed at armature and field windings, temperature distribution in stator near pole proximity was 35°C whereas no significant change in rotor temperature was noticed. Furthermore, principal stress at the speed of 3,000 rpm and 30,000 rpm was found out to be 0.0305 MPa 3.045 MPa, respectively.

Research limitations/implications

The designed machine will be optimized for improvement of electromagnetic performance followed by hardware implementation and experimental testing in the future.

Practical implications

The model is developed for axial fan applications.

Originality/value

Thermal analysis is not being implemented on FEFSM for axial fan applications which is an important analysis to ensure the electromagnetic performance of the machine.

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 1 August 1999

Jaroslav Mackerle

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the…

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1927

Abstract

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Details

Engineering Computations, vol. 16 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Content available
Article
Publication date: 5 June 2020

Krzysztof Jakub Stojek, Jan Felba, Johann Nicolics and Dominik Wołczyński

This paper aims to develop thermal analysis method of thermal joints characterization. The impact on convection on thermal resistance analysis with use thermography for…

Abstract

Purpose

This paper aims to develop thermal analysis method of thermal joints characterization. The impact on convection on thermal resistance analysis with use thermography for silver-based thermal joints were investigated for non-metallized and metalized semiconductor surfaces. Heat transfer efficiency depends on thermal conductivity; radiation was used to perform thermographic analysis; the convection is energy loss, so its removing might improve measurements accuracy.

Design/methodology/approach

Investigation of thermal joints analysis method was focused on determination of convection impact on thermal resistance thermographic analysis method. Measuring samples placed in vacuum chamber with lowered pressure requires transparent window for infrared radiation that is used for thermographic analysis. Impact of infrared window and convection on temperature measurements and thermal resistance were referred.

Findings

The results showed that the silicon window allowed to perform thermal analysis through, and the convection was heat transfer mode which create 15% energy loss.

Originality/value

It is possible to measure thermal resistance for silver-based thermal joints with convection eliminated to improve measurements accuracy.

Details

Soldering & Surface Mount Technology, vol. 32 no. 4
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 1 January 2005

K. Jeevan, G.A. Quadir, K.N. Seetharamu, I.A. Azid and Z.A. Zainal

To determine the optimal dimensions for a stacked micro‐channel using the genetic algorithms (GAs) under different flow constraints.

Abstract

Purpose

To determine the optimal dimensions for a stacked micro‐channel using the genetic algorithms (GAs) under different flow constraints.

Design/methodology/approach

GA is used as an optimization tool for optimizing the thermal resistance of a stacked micro‐channel under different flow constraints obtained by using the one dimensional (1D) and two dimensional (2D) finite element methods (FEM) and by thermal resistance network model as well (proposed by earlier researcher). The 2D FEM is used to study the effect of two dimensional heat conduction in the micro‐channel material. Some parametric studies are carried out to determine the resulting performance of the stacked micro‐channel. Different number of layers of the stacked micro‐channel is also investigated to study its effect on the minimum thermal resistance.

Findings

The results obtained from the 1D FEM analysis compare well with those obtained from the thermal resistance network model. However, the 2D FEM analysis results in lower thermal resistance and, therefore, the importance of considering the conduction in two dimensions in the micro‐channel is highlighted.

Research limitations/implication

The analysis is valid for constant properties fluid and for steady‐state conditions. The top‐most surfaces as well as the side surfaces of the micro‐channel are considered adiabatic.

Practical implications

The method is very useful for practical design of micro‐channel heat‐sinks.

Originality/value

FEM analyses of stacked micro‐channel can be easily implemented in the optimization procedure for obtaining the dimensions of the stacked micro‐channel heat‐sinks for minimum thermal resistance.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 15 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 January 1987

Zbigniew Mańko

While calculating internal forces of a structure resulting from temperature it is necessary to know thermal conduction and what goes hand in hand to determine temperature…

Abstract

While calculating internal forces of a structure resulting from temperature it is necessary to know thermal conduction and what goes hand in hand to determine temperature distribution at various points of the analysed structures. Finite strip method (FSM) is very suitable for the analysis of thermal conduction, heating, heat and temperature distribution in engineering structures, especially rectangular of identical edge conditions. The paper presents several examples of FSM application for the analysis of conduction and heat and temperature distribution for various types of engineering structures which can appear, among others, while welding several joined elements with welds made at specified speed as linear and point welds. Bars, shields, square and rectangular plates, steel orthotropic plates, steel and combined girders (steel‐concrete), box girders subject to various loads connected with heat and temperature (loaded with temperature, non‐uniformly heated surface). The obtained results may be useful in engineering practice for determining actual temperature and load capacity in individual elements of the construction.

Details

Engineering Computations, vol. 4 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 April 1987

S. Hamilton

Increasing power densities within electronic equipment have led to a rise in the number of heat related problems being experienced. This paper describes the use of…

Abstract

Increasing power densities within electronic equipment have led to a rise in the number of heat related problems being experienced. This paper describes the use of computerised thermal analysis techniques to optimise the design of passive thermal management systems for electronic equipment.

Details

Circuit World, vol. 14 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 March 1989

D.E. Riemer

This paper introduces thermal‐stress analysis methods which follow electrical engineering procedures. The spring constant or c‐value is found to be related to the…

Abstract

This paper introduces thermal‐stress analysis methods which follow electrical engineering procedures. The spring constant or c‐value is found to be related to the electrical impedance, combining dimensions and material characteristics in a performance parameter which simplifies calculations. Voltage is used to represent thermal deformation, and thermal forces are modelled as currents. Relationships equivalent to Ohm's Law are applied to calculate thermal stresses in leads or traces of surface‐mount assemblies. The thermal performance of laminates, e.g., thermal expansion coefficients of interconnect boards with a restraining core, and the thermal stresses in the bonded layers, are derived from the analysis of an electrical network which represents the composite structure. The method provides visual concepts which facilitate a first‐order solution of engineering problems related to thermal stress.

Details

Soldering & Surface Mount Technology, vol. 1 no. 3
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 14 March 2019

Wei-Mon Yan, Hsu-Yang Teng, Chun-Han Li and Mohammad Ghalambaz

The electromagnetic field and cooling system of a high power switched reluctance motor (SRM) are studied numerically. The geometry of the motor and its main components are…

Abstract

Purpose

The electromagnetic field and cooling system of a high power switched reluctance motor (SRM) are studied numerically. The geometry of the motor and its main components are established using a computer-aided design software in the actual size. This study aims to evaluate the resulting thermal losses using the electromagnetic analysis of the motor.

Design/methodology/approach

In the electromagnetic analysis, the Joule’s loss in the copper wires of the coil windings and the iron losses (the eddy currents loss and the hysteresis loss) are considered. The flow and heat transfer model for the thermal analysis of the motor including the conduction in solid parts and convection in the fluid part is introduced. The magnetic losses are imported into the thermal analysis model in the form of internal heat generation in motor components. Several cooling system approaches were introduced, such as natural convection cooling, natural convection cooling with various types of fins over the motor casing, forced conviction air-cooled cooling system using a mounted fan, casing surface with and without heat sinks, liquid-cooled cooling system using the water in a channel shell and a hybrid air-cooled and liquid-cooled cooling system.

Findings

The results of the electromagnetics analysis show that the low rotational speed of the motor induces higher currents in coil windings, which in turn, it causes higher copper losses in SRM coil windings. For higher rotational speed of SRM, the core loss is higher than the copper loss is in SRM due to the higher frequency. An air-cooled cooling system is used for cooling of SRM. The results reveal when the rotational speed is at 4,000 rpm, the coil loss would be at the maximum value. Therefore, the coil temperature is about 197.9°C, which is higher than the tolerated standard temperature insulation material. Hence, the air-cooled system cannot reduce the temperature to the safe temperature limitation of the motor and guarantee the safe operation of SRM. Thus, a hybrid system of both air-cooled and liquid-cooled cooling system with mounting fins at the outer surface of the casing is proposed. The hybrid system with the liquid flow of Re = 1,500 provides a cooling power capable of safe operation of the motor at 117.2°C, which is adequate for standard insulation material grade E.

Originality/value

The electromagnetic field and cooling system of a high power SRM in the presence of a mounted fan at the rear of the motor are analyzed. The thermal analysis is performed for both of the air-cooled and liquid-cooled cooling systems to meet the cooling demands of the motor for the first time.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 2 March 2015

Marcin Lefik

The purpose of this paper is to include thermal analysis in the design process of permanent magnet synchronous motor (PMSM). The additional objective is a comparison of…

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338

Abstract

Purpose

The purpose of this paper is to include thermal analysis in the design process of permanent magnet synchronous motor (PMSM). The additional objective is a comparison of PMSM with induction motor (IM) in terms of thermal phenomena.

Design/methodology/approach

Numerical investigation using commercial software MotorSolve was performed. Parameterized models of PMSM and IM were used. Calculations of motor parameters and temperature distribution were made using Finite Element Method.

Findings

The results of the calculations show that thermal calculations should be included in the design process because the maximum permissible operating temperature of permanent magnets should not be exceeded. A comparative analysis of PMSM and IM shows that the PMSM has better parameters than the IM which was used as a base of the PMSM construction.

Research limitations/implications

Computational models should be verified experimentally on a physical model or by using more complex numerical models. In the case of IM thermal calculations, a method of air speed calculation should be proposed. Air speed is a parameter that is necessary in thermal analysis of IM, but during the design process it is unknown.

Originality/value

This paper presents modelling methodology of 3D transient thermal field coupled with electromagnetic field applied in a three-phase IM at rated load conditions. This paper presents a design strategy which includes thermal analysis of the designed PMSM. Moreover, the paper shows a comparison between PMSM and IM indicating advantages of PMSM over IM.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 30 April 2019

Mariusz Baranski

This paper aims to elaborate the method and algorithm for the analysis of the influence of high temperature on electric and thermal properties of the materials, as well as…

Abstract

Purpose

This paper aims to elaborate the method and algorithm for the analysis of the influence of high temperature on electric and thermal properties of the materials, as well as thermal phenomena process.

Design/methodology/approach

The paper presents specially author’s software for the transient finite element analysis of coupled electromagnetic-thermal problems in a squirrel cage induction motor. The numerical implementation is based on finite element method and step-by-step algorithm. The nonlinearity of a magnetic circuit, the dependence of electric and thermal parameters on temperature, the movement of a rotor and skewed rotor bars have been taken into account. To verify the developed algorithm and software, the influence of high ambient temperature on selected electromagnetic and thermal parameters of the induction motor was examined.

Findings

The results of simulations compared with measurements confirm the adequacy of this approach to the analysis of coupled electromagnetic-thermal problems.

Research limitations/implications

3D effects have only been taken into account when using quasi-3D techniques (e.g. the multi-slice for skewed rotor slots).

Practical implications

The author’s software developed can be useful in the analysis and design of squirrel cage motors, especially motors working in high ambient temperature.

Originality/value

The paper offers appropriate author’s software for the transient and steady-state analysis of coupled electromagnetic and thermal problems in squirrel cage motors with skewed slots.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 38 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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