Iraqi journal of mechanical and material engineering

In this paper, a FEM is used to determine the effect of die design on sheet
hydroforming process. The hydraulic deformation is a process for sheet forming by applying
hydraulic pressurized liquid on the sheet. This process is characterized by its ability to give
homogenous strain distribution along the blank with highly mechanical properties. To
simulate deformation process and analyze the results theoretically, a special programmer for
finite elements (Ansys15) has been used. To prove rightness of numerical simulation, a die
with the same dimensions of used die in research has been built. The simulation of the
sample deformation process has been performed by using circular plate of aluminum alloy
(1435) with two different thickness (1)mm using four profile radius for lower die
(2,4,6,8,10)mm and under effect of (10) KN blank holder force(BHF). These parameters
have been used to know the effect of die profile radius and blank holder force on the product
in term of stresses distribution and wrinkling and tearing and average of thickness change
along the length from the center of the sample to the final edge on the accuracy and the
shape of final product.

Laser surface treatment is an effective way to improve the characteristics of surface layers
for the most alloys. In the present work, three different steel alloys: low carbon steel A3115,
medium carbon steel 1045 and high carbon steel 52100 were hardened by Nd: YAG laser at
1.064nm wave length with 1000mj energy. An experiments with Nd: YAG laser were carried
out to study the effect of laser hardening process on the microstructure, roughness,
microhardness during laser hardening of the three alloys. All of surface layers characteristics
were analyses using optical microscope. Laser surface treatment enhanced the characteristics
of surface layers for all the alloys. Also Nd: YAG laser surface treatment produced plate
martensite for 52100 alloy more than A3115 and 1045 alloys. From the results is obtained
finer martensite, an excellentroughness and larger microhardness for this alloy. The aim of
present investigation study the effect of Nd: YAG laser hardening on the characteristics of
surface layers for three different steel alloys (A3115, 1045, 52100) .

In the present work it has been studied the effect of (0.3, 0.8 and 1.5 wt.%) Zirconia ZrO2
and Hydroxyapatite (HAp) nanoparticles on polymer blend matrix (poly methyl
methacrylate (PMMA) / High density polyethylene (HDPE. SEM Morphological analysis
has been performed which shows different morphologies with various contents of polymer
blend composites. Mechanical tests including (tensile, compression, flexural, Impact and
wear) were performed on the two groups of binary blend composites. Zirconia blend
composites gave higher values of mechanical characteristics as compared with the
hydroxyapatite ones. Wear resistance showed improvement with the addition of nano
powders still, the effect of addition hydroxyapatite to polymer blend, was better as
compared with that of zirconia.

An experimental study on laminar flame speed of the premixed Iraqi liquefied
petroleum gas (LPG)-hydrogen /air flames is conducted in a centrally ignited constant
volume chamber specially constructed by the authors; at different initial pressures (0.1-
0.3MPa) and initial temperature of (308 K). The tests are carried out at a mixture
equivalence ratio ranges from 0.8-1.3. The investigated blends of hydrogen are 0-80% by
volume .
Experimental results show that the effect of hydrogen addition becomes obvious when the
hydrogen blend is larger than 60%. When hydrogen blending 80%, the laminar flame speed
of LPG also increases from (2.2-4.75 m/s) for stoichiometric mixture at atmosphere
pressure. Increasing initial pressure from (1-3 bar), reduces stretched laminar flame speed of
LPG-air mixture from (2.2-1.5 m/s) .

In this work a new concept of flow separation control mechanism has been introduced to
improve the aerodynamic characteristics of an airfoil. Control of flow separation over an
airfoil at low Reynolds number is theoretically simulated under the effects of suction and
blowing, based on the computation of Reynolds-average Navier-Stocks equations(the
solution of each set of equations is achieved by application of the SEP(strong explicit
procedure)solver) is carried out. Using Finite Volume Method to solve the governing
equations on a body, so, a numerical model is developed. The suction and blowing control
mechanism appears to be suppression of the separation bubble and reduction of the upper
surface pressure to increase the lift and decrease the drag. To make section model, NACA
4421 airfoil has been chosen. In present study, the theoretical are performed with different
angle of attack (20º, 22º, 23º), Uj/U (A) =6 and different chord (1c,0.9c,0.8c,0.7c). The
theoretical results show that the flow separation control is possible by the proposed
mechanism and benefits can be achieved by suction and blowing (for suction position at the
end of the chord (0.8c) and for blowing position at the begging of the chord (0.1c)). The
section performance is significantly improved due to control of flow separation by suction
and blowing. It has also been found that the lift increases about 14% at the angle of attack
20º, 22ºand 23º and seen that the blowing is better than the suction.

In this work, the effect of adding natural additives such as rice husks ash and nano additives
such as TiO2 to the electrolyte on the properties of ceramic oxide coating formed on 2024 Al
alloy substrate by micro arc oxidation (MAO). Results proved that the formation of hard
ceramic oxide coatings were values(313 to 531.3)HV. Roughness increased with deposition
time increasing, thickness of coatings variation with deposition time. Morphology of coated
sample for 45min with electrolyte compositions(10g/l KH2PO4, 5g/l NaCO3, 4g/l H3PO4, 6g/l
(NH3)2MO7O24,3g/l RHA, and 9g/l KOH, 1g/l nanoTiO2)showed the dense structure and
uniform pores distribution, increasing the addition of TiO2to 3g/lthe results showed that more
porous structure. Wear resistance of coatings improved by means of decreasing loss weight
from (0.0017g of substrate) to (0.0003-0.0009)of samples at (15min and 60min) respectively,
with composition(1g/l nanoTiO2, 10g/l KH2PO4, 5g/l NaCO3, 4g/l H3PO4,6g/l
(NH3)2MO7O24,3g/l RHA, and 9g/l KOH) .

Friction stir processing (FSP) is a novel solid state process to produce surface composite.
In this study, FSP was applied to produce surface composite for (AA5086) matrix reinforced
with Silicon Carbide (SiC) particles . FSP tool of flat shoulder in diameter (18mm) and
cylindrical pin with threaded profile in diameter (6mm), length (2.5 mm) was fabricated.
The groove cut on the surface of base metal in (2mm) depth, (2.5mm) width, then groove
filled with reinforcement particles. The process carried out at various rotational speed (500,
1000, 1600 rpm) and constant traveling speed (30)mm/min. Optical microscopy and
scanning electron microscopy (SEM) are used to analysis the microstructure. Furthermore,
the wear properties of the surface composites were evaluated by using a pin on disc wear
test at room temperature at normal loads of ( 10,15, and 20 N). The results showed that
microhardness profile along top surface improved after FSP) and the maximum
microhardness evaluated at rotational speed (1000 rpm)for (AA5086) reinforced by (SiC)
particles in three passes. The microhardness increased to (150 HV) as compared with the
micro-hardness of the base metal (94HV). The practical purpose of this work is to improve
the surface wear resistance by developing a layer of ceramic composite on the surface of
(AA5086)

The heat treatment is necessary for 2205 duplex stainless steel to remove or dissolve
intermetallic phases, removed segregation and to relieve any residual thermal stress in DSS
which may be formed during production processes. In the present study, the corrosion
resistance of a 2205 DSS in artificial saliva was studied by SEM, XRD, HV test and
potentiodynamic measurements. The results indicated that the corrosion resistance mainly
effected by ferrite /austenite ratio. The best result was obtained with the treatment at 900°C
for 2 min. The austenite phase has corrosion resistance higher than ferrite.

In this study, utilizing the PCM latent heat of fusion to absorbing the heat energy from
photovoltaic panels was done. This method works as a passive cooling to regulate the PV
panel’s temperature in hot climate regions. To enhance the important effective physical
properties such as thermal conductivities (keff) for this material, aluminum foam matrix was
used with paraffin wax. This led to good temperature distribution inside PCM and more heat
absorption from PV panel. The experimental results indicated that the PV panel temperature
drooped from (61.39 oC) to (46.2 oC) by using PCM only, and to (39.58oC) by using
PCM/Aluminum foam matrix at the test end, (i.e. the percentage drooping of PV panel
temperature was (25.03%) by using PCM only, and it was (35.51%) by using
PCM/Aluminum foam matrix). This droop in temperature enhances the electrical
performance of PV panel such as maximum power generated, fill factor (FF), etc. The
improving in electrical efficiency of PV panel at the test end was from (10.19%) to
(12.37%) with using PCM only, and to about (13%) with using PCM/Aluminum foam
matrix

This paper aims to clear some influential parameters, like shape and size of shot-peening
on pitting corrosion for aluminum alloy 6061-T6. Many specimens" were "prepared for
corrosion test" with dimensions of (15*15*3) mm according to ASTM G71-31 and these
specimens were categorized into four group having symbols (A,B,C,D). Three of these
groups were shot peened using different ball sizes. Group B shot by steel ball having
diameter 1.25 mm while group C shot by steel ball with diameter 2.75 mm. Steel cylinder
with diameter of 2.75 mm" and length 3mm was to shot" another "specimens. Shot "time"
was fixed of (10) min. Many tests have been carried out to measure the surface roughness,
Vickers hardness ,residual stresses. SEM micrograph for all specimens . Corrosion test
was done by cyclic electrochemical methods for all specimens in environments of "3.5%
NaCl solution". The Corrosion value has calculated by using Tafel equation. Results
obtained show that shot peening contribute in decreasing corrosion rate comparing with base
metal and shot peening using steel ball give low corrosion rate than cylinder steel due to
plastic deformation causes by cylinder steel and steel ball having diameter 2.75 give the best
result due to residual stress

Visual servoing (VS) is an essential research field because it is included in several robots'
applications, such as "navigation and visual surveillance". The VS comprises three stages:
taking an image by a visual sensor, processing the image to detect a target object, and
guiding the robot to navigate the object. In this work, this issue will be studied to find the
object's position in the frame of the image; and then to estimate its distance from the robot
frame. The paper will provide the fundamental information of using two techniques: mono
and stereo vision. C++ programming in addition to OpenCV libraries were used to develop
and implement all codes. The experimental results demonstrated that the distances
measured by stereo-vision were relatively accurate with errors ranged from -2.0 to 2.6 % in
comparison with mono-vision's measurement errors that were fluctuated between -6.4 and
2.5%. It was also verified that the better results were achieved by using the larger distance
between the cameras within the stereo-vision system.

Poly Methyl Methacrylate were widely accepted material in dental and medical field due to
the excellent biocompatibility and easy fabrication, however exhibit inferior mechanical
properties. Therefore, the present study conducted to determine the flexural properties of
PMMA based material by reinforcing PMMA with two different natural fibers (bamboo &
siwak fibers). Discontinuous random fibers used in three lengths (2, 6 & 12 mm) and three
weight percentage (3, 6 & 9 wt. %) of the both types of fibers. Results indicated that
Flexural modulus, flexural strength and max.shear stress increase with increasing weight
fraction and fiber length of fibers (bamboo & siwak) and reach the maximum amount at
addition of weight fraction of (9 wt.%) and (12mm) length of fibers. The highest value of
flexural modulus, flexural strength and max.shear stress were (10.09GPa), (112MPa),
(6MPa) respectively, for composite specimens with bamboo fibers, while for composite
specimen with siwak fibers (9.71GPa),(101MPa),(4.44MPa) at the optimum condition of
(9wt.%) and (12mm) length . All composite specimens reinforced with bamboo fibers
showed the highest flexural strength and flexural modulus among the composite specimen
reinforced by siwak fibers.

This research involved the enhancement of heat transfer and flow in a tube filled with a
porous medium by using hybrid nanofluids. The theoretical model contains the governing
equations to the flow and heat transfer through porous media by using the Darcy flow model
with uniform heat flux on the surface tube. The porous medium consist of glass beads (dp =
20 mm) and one type of filling material. The simple algorithm is used to solve momentum
and continuity equations after combined these equations to configure the pressure
correction formula. The results of this study represented by different parameters such as
Rayleigh number (Ra=103,105,106), type of hybrid nanoparticles,volume fraction (Φ =1, 3
and 5% vol), and angles of tube (α =300, 450 and 900) through contour secondary flow and
isotherms. The results also show that average Nussult number various with Rayleigh
number, type of the hybrid nanoparticles and constant of Peclet number ( Pe =20). The
results of numerical solution indicated that the impact of free convection appears at the start
region of the tube and its maximum impact happen in the horizontal position then this effect
decreases to the vertical position when inclination of the tube increses. Moreover the
concentration of hybrid nanoparticles has an insignificant impact on the stream lines,
tangential and radial velocities distribution, skin friction coefficient and porous media. The
heat transfer increases with the increase concentration of hybrid nanoparticles and Rayleigh
number. On the other hand the type and synergistic of hybrid nanoparticles play important
role in improvement of heat transfer. The improvement for hybrid nanofluid is
(Cu(25nm)+Al(25nm)+Dw) (33%) while for hybrid nanofluid it is (Al2O3(50nm)+TiO2
(50nm)+Dw) was (24%) respectively.

In This paper, a numerical simulation that was made in the three-dimensional flow, carried
out in a modified centrifugal compressor, having vaned diffuser stage, used as an automotive turbo charger. In order to study the influence of vaned diffuser meridional outlet
section with a different width ratio on the modified centrifugal compressor. Moreover, the
performance of the centrifugal compressor was dependent on the proper matching between
the compressor impeller along with vaned diffuser. In addition, the curves of polytropic
efficiency, total pressure ratio, static pressure and aerodynamic characteristics were
compared under different width ratio. In addition, the velocity vectors in diffuser flow
passages, the absolute Mach number and the secondary flow in cross-section near the outlet
of diffuser were analyzed in detail under width ratio of 0.5, 0.7, 0.8, 1 and 1.2. Another aim
of this research was to study and simulate the effect of vaned diffuser on the performance of
a centrifugal compressor. The simulation was undertaken by using CFD analysis on
aerodynamic flow to predict numerically the performance in terms of pressure ratio, poly
tropic efficiency and mass flow rate for the centrifugal compressor stage. The results were
generated from CFD (ANSYS CFX) and were analyzed for better understanding of the fluid
flow through centrifugal compressor stage and as a result when the width ratio is 0.5, the
flow in diffuser passages tends to be uniformity. The backflow and vortex near the pressure
surface disappear, and the vortex and detachment near the suction surface decrease.
Conclusively, it was observed that the efficiency was increased and both the total pressure
ratio and static pressure for 0.5 width ratio are increased .

Sound absorption in living, traveling and working environment constitutes one of the
major requirements for human comfort today. Sound insulation requirements in
automobiles, in manufacturing environments, and in equipments, generating higher sound
pressure, strives the need to develop more efficient and economical ways of producing
absorption materials. Traditionally, economics of recent research has enforced the research
to focus on waste materials.
The aim of this study is to use waste materials (particles of egg shell, palm leaf, jute,
wood dust, chicken feather) for producing reinforced and polyester resien composite
structures with 17% weight fraction. Two natural material composite plate shapes (flat and
corrugated) with the same area is manufactured, where the echoic chamber is built and
insulated with cork and sponge for different inside wall shape (flat, concave and pyramids) .
The study concluded that the jute woven and saw dust composite exhibited a greater ability
to absorb normal incidence sound waves than the composites with chicken feather, particles
of egg shell, and palm leaf fiber for different shape cork and sponge insider insulator. The
analysis of sound transmission loss revealed that the particles of egg shell and saw dust still
obeyed the mass law of transmission loss. The composite surface layer of particles of egg
shell and saw dust possessed a higher fabric density and therefore showed a better sound
insulation than the composites with jute woven, chicken feathers, and palm leaf.
KEYWORDS: natural composite materials, absorption properties, insulation.

Several Experiments have been done to evaluate the effect of blending kerosene (by
different volume) with diesel fuel on the performance and emissions of a single cylinder 4-
stroke air cooled DI diesel engine connected with a hydraulic dynamometer which is used to
load the engine that running at fixed speed with different loads (torques). Two levels of
blend 10% and 20% of kerosene blending by volume with diesel fuel were named KD10 and KD20 respectively, while pure diesel was considered as a baseline and named D. The engine
speed was running at constant speed 1500 rpm.the treatments include three levels of load
(torque) 2, 6 and 10 N.m and three types of fuels D, KD10 and KD20. Performance
parameters that were studied involve brake specific fuel consumption (bsfc), brake thermal
efficiency (BTE), brake specific energy consumption (bsec), Exhaust Gas Temperature
(EGT) and sound level. Furthermore, the exhaust emissions were analyzed to find the effect
of selected blends on Carbon Dioxide (CO2) and Nitrogen Oxides (NOx). The results
showed the possibility of using KD10 in diesel engine instead of diesel fuel D without any
modification done on the engine as there is no significant difference registered in bsfc, BTE
and bsec at full load, while using KD10, KD20 recorded a decrease in CO2 emissions by
8.8% and 27.3% respectively compared to fuel D at high loads also they recorded an
increase in NOx emissions by 16.6% and 31.2% respectively compared with using diesel
fuel . The results showed that using KD10, KD20 instead of fuel D showed an increase in
EGT and sound level for all ranges of selected torques

The present work refer to the mechanism used for supplying drinking water to Baghdad city
; After the first Gulf War , Baghdad province has seen a clear scarcity of water that it's
caused Iraqi consumer to use pumps in supplying water because of lower the networks
pressures, this is unacceptable from the engineering point of view for many reasons
discussed in the work, therefore it was awarded an import costs for these pumps since 1995
to 2015 with calculating the cost create high tanks by advanced engineering
specifications(old systems) which was formerly using to study the negatives brought about by water supply systems by modern methods In order to determine activity, vitality to
optimal water supply for residential neighborhoods to what it was in the eighties of the last
century , where the water up to the top of the houses points and with new design pressures
,This study found a number of recommendations that deal with the case or situation in
order to get rid of many from the excesses brought about by current methods and there is a
big difference in prices ,this case can be corrected by providing high economy of the state
and with high-efficiency engineering service to the consumer . the indiscriminate import to
massive amounts of small pumps and just start taking this research in the field of
application , as a result the huge amounts of money will be made available to the country
that is wasted because of poor planning for future phases