Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Finite element method


Design and Performance Analysis of Permanent Magnet Synchronous Motor for Electric Vehicles Application

Mustafa Y. Bdewi; Ahmed M. Mohammed; Mohammed M. Ezzaldean

Engineering and Technology Journal, 2021, Volume 39, Issue 3, Pages 394-406
DOI: 10.30684/etj.2021.168120

In electrical vehicle applications, power density plays a significant role in improving machine performance. The main objective of this paper is to design and analyze the performance of in-wheel outer rotor permanent magnet synchronous motor (PMSM) used in electric vehicles based on a previously designed model. The key challenge is to achieve the best machine performance regarding the highest torque density and lowest torque ripple. This work also aims at reducing the machine cost by using permanent magnet (PM) material, which has less energy density than the PM used in the previously designed model. An optimization procedure is carried out to improve the generated torque, keeping the same aspects of size and volume of the selected machine. On the other hand, the other specifications of the machine are taken into consideration and are maintained within the acceptable level. According to their major impact on the machine’s performance, the most important parameters of machine designing is selected during the optimization procedure. This proposed machine is implemented and tested using the finite element software package “MagNet 7.4.1” with Visual Basic 16.0 programming language and MATLAB 9.5 Simulink for post-processing.

Experimental and Numerical Analysis of Piled Raft Foundation Embedded within Partially Saturated Soil

M.R. Mahmood; S.F.A. Al-Wakel; A.A. Hani

Engineering and Technology Journal, 2017, Volume 35, Issue 2, Pages 97-105

This paper presents an experimental and numerical study to investigate the load carrying capacity of piled raft foundation embedded within partially saturated sandy soil. The effect of matric suction on the bearing capacity of the foundation system was investigated. The experimental work consists of two models of foundation, circular raft foundation and circular piled raft foundation. The circular raft foundation has dimensions of 10cm in diameter, and 2.5cm thickness, while the piled raft foundation has the same dimensions of the circular raft model but with a single pile of 2.0cm in diameter and 40.0cm in length fixed at the center of the raft. Both models are loaded and tested under both fully saturated condition and unsaturated conditions, which are achieved by, predetermined lowering of water table. The lowering of water table below the soil surface was achieved in to two different depths to get different values of matric suction and the relationship between matric suction and depth of ground water table was measured in suction profile set by using three Tensiometers (IRROMETER). The soil water characteristic curve (SWCC) estimated by applying fitting methods through the software (SoilVision). A validation process then was carried out for the case of circular piled raft foundation with lowering the water table 45cm bellow soil surface in the aid of a sufficient finite element computer program ABAQUS 6.12. An eight-node axisymmetric quadrilateral element CAX8RP and CAX8R were used to simulate the soil continuum and piled raft respectively. The interaction method used to simulate the intersect surfaces of the system (pile-raft-soil) is a surface-to-surface discretization method under the concept of master and slave theory. The behavior of piled raft material is simulated by using a linear elastic model while the behavior of soil is simulated by an elasto-plastic model by the use of the Mohr-Coulomb failure criterion. The results of the experimental work demonstrate that the matric suction has a significant role on the bearing capacity of all tested models. It shows that the ultimate bearing capacity of circular raft foundation under a partially saturated condition is increases by about (7.0-8.0) times than the ultimate bearing capacity of fully saturated condition when lowering the water table 45 cm below the soil surface. While the ultimate bearing of circular piled raft foundation under partially saturated condition increases by about (8.0-9.0) times than the ultimate bearing capacity of fully saturated condition when lowering the water table 45 cm below the soil surface. The results of the ultimate bearing capacity of piled raft foundation that obtained from the experimental model and from the numerical modelling for the same soil condition and same matric suction indicate that a successful validation is achieved for the simulation process.

Thermal Lensing Reduction in Conventional and Composite Nd:YAG Laser Rod

Mohammed Jalal AbdulRazzaq; Abdulla K. Abass; Wail Yas Nassir

Engineering and Technology Journal, 2016, Volume 34, Issue 11, Pages 2031-2035

A finite-element method (FEM) wasused to simulate numerically the effect of thermal lensing in YAG rods doped with Nd ion using LASCAD software. The temperature distribution and thermal lensing focal length of the composite laser rod (YAG/Nd:YAG) with one undoped end cap was considered and compared with conventional laser rod (Nd:YAG) by applying software. Results show that thermal lensing effects were reduced by a factor of 2 using (YAG/Nd:YAG) composite rod at pump power of 20W.

Study of the Influence of the Elastic Rubber Cushion on Product Quality Formed by a Multi - Point Forming (MPF) Process

Marwa Sabah Fakhri; Sadiq Jaffar Aziz

Engineering and Technology Journal, 2016, Volume 34, Issue 3, Pages 452-463

The Multi-Point Forming (MPF) is an advanced flexible manufacturing technology for three – dimensional sheet metal forming. This is replacing the conventional solid dies by a set of discrete punches called (punch group).
This work presents the design and manufacturing of (MPF) dies. It covers also, the effect of using an elastic cushion on the quality of products. This technique eliminates the formation of dimples which, otherwise reduces the quality of product. The work falls into two parts. Part one includes the use of ANSYS, which employs a finite element method (FEM) for the simulation of MPF components, namely: upper jaw, lower die and cushion. In the other part (experimental), a complete MPF die was designed and manufactured in the local market.
The copper sheet metal was selected to study the influence of the elastic cushion on the quality of product which formed by MPF process. This rubber was used to avoid the dimples occurring on the metal surface. Experimental and numerical results showedthatthis technique produces a better quality free from dimples. The cushion proved to be effective in elimination of the thickness change. The thickness change was found to be in the range (0-0.05) for a blank of 2 mm.
Hence, it is recommended that the (MPF) method is effective in product quality. However, two layers of cushion are necessary to separate between the workpiece and pins to reduce the work piece deformation. Also, the numerical simulation was used by (ANSYS) software which was compared with the experimental result. A good agreement for numerical and experimental results was found.

Effect of Stress Level on Behavior of Bored Piles Embedded in Medium Sandy Soil

Kais T. Shlash; Mohammad A. Al-Neam; Saif I. Akoobi

Engineering and Technology Journal, 2013, Volume 31, Issue 19, Pages 29-43

In this paper investigation in the end bearing and shaft resistance of bored piles embedded in medium sand and subjected to axial load for wide rang of stress levels starting from laboratory dimensions and go toward field dimensions were made by utilizing the finite element method. The soil is modeled using hyperbolic soil model with empirical equation account for reduction of angle of internal friction Ø with increase in stress level while the bored pile assumed as a linear elastic material. It was found that the stress level has a significant effect on pile’s behavior and the small scale model in laboratory dimension not represent the real behavior of pile in field dimensions and if the results from such dimensions are adopted, it will lead to overestimate of bearing capacity factor Nq. Also, the effect of embedment ratio (L/D) on pile’s behavior is examined in this study and the results showed that the embedment ratio (L/D) increases the bearing capacity factor Nq up to a certain length beyond it the effect of embedment ratio (L/D) diminished.

Effect of Stress Level of Surrounding Soil on Bored Pile Capacity in Sand

Kais T. Shlash; Mohammed A. Mahmoud; Saif I. Akoobi

Engineering and Technology Journal, 2013, Volume 31, Issue 15, Pages 2839-2859

This study deals with assessing the effect of stress level on bearing capacity
factor , distribution of shear stresses at soil-pile interface along pile shaft, and
presence of critical depth concept for bored piles axially loaded in compression and
embedded in dense sand. These investigations are made using finite element method
with the employment of a wide range of stresses by using piles with dimensions
starting from laboratory dimensions and goes towards field dimensions with
embedment ratio range from (15-40). The soil and the interface behavior is
modeled using Duncan-Chang hyperbolic soil model with empirical equations
account for reduction of angle of internal friction ø with increasing in stress level.
Bored pile is modeled as a linear elastic material. The results showed a dramatic
decrease in bearing capacity factor as length of pile increase. It was also found
that the embedment ratio has a significant effect in increasing bearing capacity
factor , and the distribution of shear stresses at soil-pile interface is not linear and
does not tend to take a constant value beyond a certain depth of pile nor decreases
after a certain depth along pile shaft. The fallacy of critical depth also noticed and
discussed in this paper.

Nonlinear Finite Element Analysis of Reinforced Concrete Arched Beams with Normal and High Compressive Strength

Haider Kadhim Ammash

Engineering and Technology Journal, 2013, Volume 31, Issue 9, Pages 1732-1752

This study describes a three-dimensional nonlinear finite element model suitable for the analysis of high strength reinforced concrete arched beams under static load. The twenty node isoperimetric brick element has been used to model the concrete and reinforcing steel bars have been idealized as axial members embedded within the brick elements. Perfect bond was assumed to occur between the concrete and the reinforcing bars. The behavior of concrete in compression is simulated by an elasto-plastic work hardening model followed by a perfectly plastic response, which is terminated at the onset of the crushing. In tension, a smeared crack model with fixed orthogonal cracks has been used. High and normal strength reinforced concrete arched beams have been analyzed in the present study. Parametric studies have been carried out to investigate the effect of radius to span length ratio, boundary conditions, (α2) [the sudden loss of stress at the instant of cracking], and effect of compressive strength. In general good agreement between the finite element solutions and the experimental results have been obtained.

Method for Shielding the Magnetic Field Generated in a 132/33/11(6.6)KV Baghdad Indoor Distribution Substation

Suad I. Shahl

Engineering and Technology Journal, 2012, Volume 30, Issue 15, Pages 2562-2576

This research introduces the study carried out on one of Baghdad East 132/33/11(6.6) kV distribution substations to mitigate 50Hz magnetic field of indoor distribution substation under normal operation. Shielding was performed at the power sources such as busbars rather than at the affected areas. Three-dimensional finite element method (FEM) is used to calculate the magnetic field density in the space nearby the busbars so as to analyze the shielding effectiveness of an eddy current shield applied to a 132/33/11(6.6)kV substation. It also deals with the influence of shield distance from busbar, thickness and material of shield on the eddy current losses and shielding efficiency applied to 3D finite element model of a particular busbar configuration.

Experimental and Theoretical Study of Square Deep Drawing

Karem Muhsin Younis; Adil Shbeeb Jaber

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2456-2467

This work aim to study the effect of process parameters used in square deep
drawing operation such as ; die and punch profile radius, blank size, blank shape, on
produced cup wall thickness, strain distribution across the wall of the drawn part,
punch force, earing shape and height of the drawn cup. 3-D model of square cup
(41.4mm by 41.4mm), and 0.7 mm thickness from Low carbon steel (AISI 1008), has
been developed. Because of the symmetry in the specimen geometry, only one fourth
portion of the model was needed to be analyzed using finite element method, a
commercial available finite element program code (ANSYS 11), is used to perform
the numerical simulation of the deep drawing operation, and the numerical results of
earing shape were compared with the experimental work. In this work, three types of
blank shape (circular, square, and octagonal), with different sizes, four types of punch
profile radii of 3, 5, 6, and 7mm and three types of die profile radii of 3, 5, 7mm have
been chosen to form a square cup. The results show that, excessive earing will appear
in the square cup when square blank was used, due to excessive material in the corner
and minimum material in the flat side, and when using octagonal blank which have an
equivalent surface area to the square blank, the earing in the cup corner is reduced
because of extraction of the excessive material from the corner of the blank. The best
results were obtained from the circular blank, according to useful drawing height and
earing.

Application of GIS for the Evaluation of Electromagnetic Field Effects for Iraqi 132KV Electrical Transmission System

Afaneen A. Alkhazraji; Suad I. Shahl

Engineering and Technology Journal, 2011, Volume 29, Issue 9, Pages 1751-1764

This research endeavors to create the 50Hz electromagnetic field atlas for
populated urban areas in the city of Baghdad (Iraq). For this purpose, the 3-
dimensions numerical model based on finite element method (FEM) with time
harmonic system is used for simulated and modeling electric and magnetic fields
surrounding the 132kV transmission system. The calculated magnetic and electric
field levels are compared to exposure guidelines given by International Commission
on Non-Ionizing Radiation Protection (ICNIRP). To assign the dangers regions in the
city, the properties of the Geographical Information System (GIS) were used. The
GIS map highlighted visually the unsafe zones and facilitate the extraction of the
electric and magnetic field levels of exposure.

Influence of Corrosion Rate on the Double Butt Welding Shapes Design for Low Carbon Steel

Hani Aziz Ameen; Khairia Salman Hassan; Walid Khalid Abdul Kader

Engineering and Technology Journal, 2011, Volume 29, Issue 6, Pages 1094-1106

The aim of this paper is to demonstrate the influence of butt welding shapes
on the corrosion rate, microstructure and temperature of carbon steel type
St37.The double butt welding was performed by V angles 15°,30° and 45°. The
finite element analysis via ANSYS software is performed, this analysis includes a
finite element model for the thermal welding simulation. The temperature
distribution was obtained. From the results of the microscopic structure it is
evident that the geometric shape has an important role in the welding process,
when the geometric value of the welding region gets bigger, the faults get less due
to increase of heat quantity in the welding region and the corrosion rate for the
rain water is less than of sea water. The work presents the finite element model for
numerical simulation of welding in carbon steel St37 double butt welding.

Influence of Butt Welding Shapes Design on the Microstructure and Stresses of Low Carbon Steel

Hani Aziz Ameen; Khairia Salman Hassan

Engineering and Technology Journal, 2010, Volume 28, Issue 15, Pages 5036-5047

The aim of this paper is to demonstrate the influence of butt welding shapes on the microstructure, temperature and equivalent stresses of carbon steel type St- 37.The single butt welding was performed by V angles 15°,30°,45° and U shape. The finite element analysis via ANSYS software is performed , this analysis includes a finite element model for the thermal and mechanical welding simulation. The equivalent stresses and temperature distribution were obtained. From the results of the microscopic structure it is evident that the geometric shape
has an important role in the welding process, when the geometric value of the welding region gets bigger, the faults get less due to increase of heat quantity in the welding region. The work presents the finite element model for numerical simulation of welding stresses in carbon steel St-37 butt welding. The welding simulation was considered as a direct coupled thermo- mechanical analysi.s

Effect of Shaft Misalignment on The Stresses Distribution of Spur Gears

Hani Aziz Ameen

Engineering and Technology Journal, 2010, Volume 28, Issue 7, Pages 1321-1339

Shaft misalignment is considered as one of the common repeated
problems in most rotating machineries , which leads to generate vibrations and
extra dynamic loads on transmitting gears teeth, also leads to non- uniformity in
distribution of applied load along the meshing tooth face by being concentrated on
one side of tooth face. The present work concentrated on the analysis of stresses
generated on transmitting gear tooth, also studied the effect of misalignment angle
on stress distribution and its concentration. This is important for the gear design
and those who works in gear maintenance , because fracture is expected to initiate
and propagate at locations of stress concentration . ANSYS program using finite
element technique had been used, as this program is efficient and accurate tool in
stress analysis, especially for complicated shapes. Gear tooth model had been
analyzed using finite element method in three dimensions. After calculating
transmitted load and dynamic load, misalignment angle had been changed from
(0°,0.2°,0.3°,0.4°,0.5°) then its effect on distribution of applied load had been
calculated. The finite element program (ANSYS) had been executed for cases of
misalignment angle (0°,0.2°,0.3°,0.4°,0.5°). The results showed clearly, that the
stresses distribution and its concentration on tooth changed with misalignment
angle and the equivalent stress is direct proportional with the misalignment angle.
According to the values of generated stresses, the tooth fracture can be predicted

Effect of Dual Reinforcement on Wear Resistance by Aluminum Compacts Reinforce by SiC, Al2O3

Mohammed Moanes Ezzaldean Ali; Hanan A. R. Akkar; A. K. M. AL-Shaikhli; Ali K. Shayyish; Muhsin J. Jweeg; Wisam Auday Hussain; Mohammed T. Hussein; Mohammad A. Al-Neami; Farah S. Al-Jabary; Jafar M. Hassan; Ali H. Tarrad; Mohammed N. Abdullah; Ahmed T. Mahdi; Eyad K. Sayhood; Husain M. Husain; Nidaa F. Hassan; Rehab F. Hassan; Akbas E. Ali; Assim H Yousif; Kassim K Abbas; Aqeel M Jary; Shakir A. Salih; Ali T. Jasim; Ammar A. Ali; Hosham Salim; JafarM. Daif; Ali H. Al Aboodi; Ammar S. Dawood; Sarmad A. Abbas; Salah Mahdi Saleh; Roshen T. Ahmed; Aseel B. Al-Zubaidi; Mohammed Y. Hassan; Majid A. Oleiwi; Shaimaa Mahmood Mahdy; Husain M. Husain; Mohammed J. Hamood; Shaima; a Tariq Sakin

Engineering and Technology Journal, 2009, Volume 27, Issue 13, Pages 423-429

The producing composite materials of dual reinforcement in which the matrix material is aluminum reinforced with two types of ceramic particles : which are Alumina (50μm

Keywords

composite materials; wear test ; Al2O3; SiC: Al

Contact Stresses for Different Gear Design Parameter

Muhsin J. Jweeg; Wisam Auday Hussain

Engineering and Technology Journal, 2009, Volume 27, Issue 13, Pages 2274-2300

Gearing is one of the most critical components in mechanical power transmission
systems. This work investigates the characteristics of an Involute gear system
including contact stresses. Current methods of calculating spur gear (Non-linear
Analysis), contact stress using Hertz’s equation, which were originally derived for
contact between two cylinders. To enable the investigation of contact problems with
Finite Element Method (FEM), the stiffness relationship between the two contacts
areas is usually established through a spring placed between the two contacting areas.
This can be achieved by inserting a contact element placed in between the two areas
where contact occurs. A computer program was built up using (MATLAB 6.5). The
results of the two dimensional FEM analyses from ANSYS are presented. These
stresses are compared with the theoretical values (Hertz’s equations). Both results
agree very well. This indicates that the Finite Element Method(FEM) model is
accurate. The results of contact stress analysis indicates that increasing the geometrical
parameters (Pressure angle, number of teeth and module) lead to improve the tooth
contact stress, with the contact position, because the increasing of the geometrical
parameters will results in an increase of the tooth stiffness which leads to decrease the
tooth contact stress.

Thermal Effects on Diesel Engine Piston and Piston Compression Rings

Isam Ezzulddinyousif; Basim M. Al-Quraishi; Ahmed A. Al-Beiruti

Engineering and Technology Journal, 2009, Volume 27, Issue 8, Pages 1444-1454

This paper introduces an analytical study on the thermal effects on the diesel
engine piston and its compresion rings during the contact between the piston and its
compression rings .A three dimensional finite element model is built for the piston
and its compression rings using the ANSYS v. 8 Finite Element Analysis Code
that serves all engineering problems . The thermal analysis is made using contact
case between the piston and its compression rings .The work in this paper did not
include a convergence study.
The study includes the effects on the piston and piston compression rings
of the thermal conductivity of piston material , and the contact area .The conclusions
of this study are that the material type of high thermal conductivity is considered better
than the material type of low thermal conductivity. This means that the aluminum
alloy is considered better than the cast-iron alloy, and tapering the compression rings
from the inner side by 1 mm , leads to a reduction in the temperature values by
1.6% , 0.84% and 0.37% compared to rectangle compression rings.

Buckling Analysis of Composite Laminated Plate with Cutouts

Hani Aziz Ameen

Engineering and Technology Journal, 2009, Volume 27, Issue 8, Pages 1611-1621

The determination of critical buckling load of composite plate is an
important factor in determining the structural stability, which was done by ANSYS
program and experimental investigation was carried out on many specimens of
composite material of E-glass fiber reinforced polyester plastic materials with
different no. of layers. Five cases are studied to show the effect of cutout’s
parameter on the structural stability in which the shape ( circle, square, rectangle),
size (20, 30, 50 ) mm, rounding corner (5, 7.5, 10)mm and orientation of cutouts
(0°,30°,45°,60°) are presented . Also the effect of plate thickness (no. of layer) is
studied .
In general , the results of the square clamped laminated plates with circle
cutout come out in a good agreement. Which is decrease of buckling load of the
plates with change the shape from circle, square and rectangle and in case of cutout
size. The critical load is still constant with the radii rounding corner and increased
with increasing the cutout orientation and the thickness of the plate. The effect of
cutout will determine the increase or decrease of the buckling

Behavior of Composite Steel-Concrete Beam Subjected To Negative Bending

Husain M. Husain; Qais Abdul-Majeed; Anas H. Yousifany; Ikbal N. Korkess

Engineering and Technology Journal, 2009, Volume 27, Issue 1, Pages 53-71

This work deals with the behavior of structural continuous composite steelconcrete
beams, which are widely used in building and bridge constructions. Therefore
the structural behavior of composite beams under negative moment is a significant
subject. However experimental tests in this field are very rare and information about the
efficiency of shear connection when the slab is under tension are really few.
In the present research, available experimental tests on composite steel-concrete
beams under negative bending are theoretically analyzed using the finite element
software ANSYS. ANSYS computer program is a large-scale multipurpose finite
element program which may be used for solving several cases of engineering analyses.
The proposed three dimensional model is able to simulate the overall flexural
behavior of composite beams. This covers; load-deflection behavior, longitudinal slip at
the steel-concrete interface, and distribution of shear studs. The reliability of the model
is demonstrated by comparison with available experiment and alternative numerical
analysis which shows 9-10% difference.