Al-Nahrain Journal for Engineering Sciences

Cathodic protection in the sacrificial system is essentially a controlled
electrochemical cell; corrosion on the protected structure is shifted to the
anode. When the anode material is coupled to steel, they behave anodically and discharge current. In this work, magnesium used as sacrificial anode for the protection of carbon steel rod that
buried in soil with resistance of 1000, 1400, 1800, and 2200Ω/cm that simulate wide range of resistance of Iraqi soil. Potential distribution in different positions between sacrificial anode and the protected structure was measured with respect to copper - copper sulfate electrode, showing that the conditions for the sacrificial anode for the protection of carbon steel rod and simulate with contours. The result show that the increasing of soil resistivity is reduces anode life and impairs its performance. In addition, the changing of sacrificial anode is important because
it consumed therefore, it is important to optimize the distance of sacrificial anode from protected structure according to soil resistivity so that
avoiding the polarization that causes high consumption rate of anode.

In this search we simulate the polymer matrix composite of (epoxy) reinforced with wire of high carbon steel (Steel Reinforced Plastic) undulating and another with bend on the end and characterized of these wires by stiffness and toughness with low cost. Study was that the mechanical properties of the composite material (tensile/compression) by a program (COMSOL Multiphysics ٤.١). Results showed that when a process of tensile specimens reinforced with wire undulating increase power by (١٧٥٪) , where the power of separation ( ٣٧٢N) and
thus the highest power of the separation of the user interface of the samples reinforced wire with a bend on the end where the magnitude of the separation of the interface(١٩٧N) . The results show that compressive strength of samples of the composite of the basis of epoxy reinforced with steel wires and undulating with endings fit of Bending Strain hanging with the pregnancy and all the samples. Where we note increasing the value of compressive strength of the composite material reinforced with wire bending the ends of the wire rolling.

Electro optics effects are important
branches of nonlinear optics. In this
research olive oil has been chosen to study
its electro optical properties. Olive oil as an
organic compound has a centro symmetric
molecular structure which means that it has
quadratic electro optical properties
represented by Kerr effect. These electro
optical properties such as transmittance
versus applied voltage and birefringence
versus the square value of the applied
electric field were measured. These
properties are obtained for the two types of
olive oil (virgin and refined) by analyzing
of these properties, the Kerr constant and
Kerr coefficient for two types of olive oil
have been found at different wavelengths

This paper presents a theoretical analysis on packed bed thermal energy storage using phase change material (PCM) to improve the performance of solar organic Rankine cycle power generation system by extending its operational time demand to the night. The transient behavior of packed bed thermal energy storage using spherical capsules filled with paraffin wax as a storage unit has been studied numerically by finite difference technique for charging and discharging process .The effects of different parameters such as inlet temperature, mass flow rate, bed porosity , diameter of capsule and turbine inlet temperature have shown to be dominant parameters in determining the effective thermal efficiency of the solar ORC. It is seen that, turbine inlet temperature is plays an important role in the geometrical parameters of the packed bed .Comparison between theoretical results and experimental results of previous study for solar water heating system has been carried out where good agreement is noticed.

In this paper the influence of tool
geometry and welding parameters
(rotating speed and travel speed) on the
quality and mechanical properties by
using friction stir welded joints for
(7020-T53) aluminum alloy.
Three types of tool geometry variables
were used ( pin, shoulder and shoulder
inclination), internal defect (tunnel) was
detected by using X-Ray radiography for
all samples which are welded at welding
parameters (rotating speed and travel
speed), perfect tool geometry that gives
defect free was by increasing pin
diameter with threaded ,increasing
shoulder diameter and shoulder
inclination (2o) for safety purpose
radiography test was also performed to
examine defect free of weldments
(increasing tool dimensions and pin
threaded gives increasing stir and heat
input).
The effect of welding parameters
(rotation and travel speed) using tool
geometry that gives defect free were
investigated using different mechanical
tests including (tensile, bending and
microhardness). Macro and
microstructure change during (FSW)
process were studied and different
welding zones were investigated using
optical microscope. Based on the friction
stir welding experiments conducted in
this study the result show that aluminum
alloy (7020-T53) can be welded using
FSW process, the optimum welding
parameters 1400rpm rotational tool
speed and 40mm/min travel speed which
give the maximum welding efficiency
(83%), increasing rotational speed the
microhardness increases in weld zone
due to decreasing the grain size.

Belt is a traveling continuous system. Such a system can subjected to a
static divergence and parametric instability. This depend on whether the
system parameters are constant or varying with the time ,respectively .In
this paper ,instability problem is solved analytically .Bolotin method is used to evaluate the boundaries which separate the stable and instable regions. The present solution is checked with another solution available in the literature where the Variation principle is used .The results showed a good agreement where the maximum error do not exceed 5%. The effect of belt tension and transmitting speed on stability and natural frequency are studied. The results show that increasing belt tension can improve both buckling and parametric instability. Whilst, increasing the speed or its mean value is limited to critical values to avoid buckling or parametric instability, respectively.

This paper deals with studying the effect of the polarization properties of
sucrose solution (sugar which is dissolved in distilled water) as an active
material and proves the ability of this solution to rotate the plane of polarized light that passes through it with an angle (θ) which is called the angle of rotation. Angle of rotation depends on the molecular structure, the concentration of the dissolved substance, the path length of the light that passes through the solution, and the light wavelength. The method of measuring the transmitted power and angle of rotation is called “optical activity”. Two types of light source are used. The first one was the xenon lamp and chooses three color from it (red, green, and blue) using the
proper filters, and the second source was He-Ne laser of wavelength 632nm. In each case, the rotation angle and transmitted power were measured and the specific angle of rotation was calculated at different concentrations of the solution. The benefit of this work, as an optical
laboratory application to measure optical properties of various materials, including circular birefringence (optical rotation). It has been found that the effect of polarized solution on the rotation angles was very large for blue light when comparing with red, because of these measured angles depends on increasing polarized solution concentrations and due to the short wavelength of blue light with respect to green and red lights.

This paper assesses the water quality index of 11 streams (rivers) and the
receiving UM- AL NAAJ marshland at Misan governorate and how the water quality is improved when entered the marshland. The assessment employ the Canadian Council of Ministers of the Environment Water Quality Index (CCMEWQI) which incorporates three elements: Scope (F 1)- the number of water quality parameters not meeting water quality
objectives; Frequency (F 2)- the number of times the objectives are not met; and Amplitude (F 3)- the extent to which the objectives are not met. The index produces a number between 0 (worst) to 100 (best) to reflect the water quality. Iraqi guidelines for drinking water and the site-specific
measured values of 5 variables are used in the index calculation. Variables included in the index calculation were, water temperature, dissolved oxygen, total dissolved solids, pH, turbidity. The CCMEWQI analysis show that the average water quality of the 11 streams, feeding Um-Alnaaj marshland is rated as fair based on 2010 data, meaning that the conditions of the streams were sometimes depart from natural or desirable levels while the quality of water inside the marsh was ranging from good to excellent.

In this work , a fixed –bed system has been used to study the performance
of corn-cob as low cost adsorbent for Treatment of dispersed oil droplets in
oil-well product water in this system . In effect of initial oil content (600-1500
ppm), volumetric flow rate (2-5L/min), Bed height (25-35cm) and particle size (1.05-1.6mm) were studied. The results show that removal oil efficiency
reaches high percent with decreasing of initial oil concentration, volumetric
flow rate particle size and increasing of bed height.

This paper investigates the effect of bearing shell elastic deformation on the steady state behavior of misaligned journal bearings. Performance trends of elastic and rigid bearings with different degree of misalignment (Dm) have been compared. Bearing shell elastic deformation, thermal
effects, pressure and temperature variation for a bearing working under turbulent lubrication have been taken into consideration. It is found that misaligned bearings working at higher misalignment coefficients have higher load carrying capacity since the oil film thickness approaches to zero in this case. Considering the effect of bearing shell elastic deformation with the effect of oil film temperature causes lower values of bearing load. Some of the results obtained in this paper have been
compared with that published by other workers and found to be in a good
agreementز

This paper discussed the effect of frequency on dielectric properties of
different weight fraction of Cu powder reinforced epoxy composite materials. Dielectric properties of epoxy material was reinforced with (0, 5, 15, 30, 45) % weight fraction of Cu powder at frequencies ranges ((50Hz -106Hz) at room temperature. The results of this study show these dielectric constants and dielectric losses factor were increased
with increasing in weight fraction due to interfacial polarization. The results also, exhibit that dielectric constant (έ) and dielectric loss factor (ε”) decreased with increasing of frequency account of electric polarization changed with an electric field changed.

The sessile droplet method is used to determine the contact angle and the thickness of a large droplet of water (puddle), and the contact angle of a growing droplet experimentally. The measurements are done as the water temperature is varied within the range of 0-90 Co. Five kinds of substrates are used (iron, copper, aluminum, glass and brass) in the present work. It is found that as the temperature of the water increased both the contact angle values and puddle thickness values are decreased. Also it is shown that the contact angle is starting from 90o for very small droplets to a steady value as the droplet increases in size. A curve fitting is done to
obtain correlations for the variation of contact angle with water temperature values.