Anbar Journal of Engineering Sciences

This article presents a numerical study on forced convection of nanofluid flow in a two-dimensional channel with trapezoidal baffles. One baffle mounted on the top wall of channel and another mounted on the bottom wall of channel. The governing continuity, momentum and energy
equations in body-fitted coordinates are iteratively solved using finite volume method and
SIMPLE technique. In the current study, SiO2-water nanofluid with nanoparticles volume fraction
range of 0- 0.04 and nanoparticles diameters of 30 nm is considered for Reynolds number ranging from 100 to 1000. The effect of baffles height and location, nanoparticles volume fraction and
Reynolds number on the flow and thermal fields are investigated. It is found that the average
Nusselt number as well as thermal hydraulic performance increases with increasing nanopartiles volume fraction and baffle height but accompanied by increases the pressure drop. The results also show that the best thermal- hydraulic performance is obtained at baffle height of 0.3
mm, locations of baffles at upper and lower walls of 10 and 15 mm, respectively, and nanoparticles volume fraction of 0.04 over the ranges of Reynolds number

Responding quickly and economically to the diversification of customer needs has forced
manufacturing companies adopting approaches to delivering low cost, high quality sustainable
products based on finding a link between the design or the manufacturing processes and other
key elements of sustainability; economic, environmental, and social. However, these approaches
had limited success. The most likely reason for the lack of integration between the design and
manufacturing stages of the product and complexity of addressing the above mentioned three
key elements of sustainability due to existing of many variables in relation to design,
manufacturing, locations, logistic operations and so on. Taking into account the required
integration as well as the associated complexity of considering sustainability elements can lead
to large space alternative solutions and it is more difficult to use only exact methods to the
optimization of such problem. This paper presents a genetic algorithm (GA) approach aiming to
optimize a high sustainability performance by designing a product and the corresponding
manufacturing processes for that product. Process optimization is carried out in terms of the
highest fitness function achieved where different objectives are to be optimized simultaneously.
The proposed GA approach is applied to the industrial case example. The proposed approach can
assist decision makers to help explain when justifying their decision on what are the best product
design and its manufacturing processes to obtain high sustainability performance

The thermal and acoustic isolation properties of unsaturated polyester composites reinforced by
palm waste filler have been experimentally investigated. The composites have been prepared
using hand lay-up technique with filler weight fraction of (0%, 3%, 5% and 7%). Three types of
palm waste that (Date seed, old leaf bases and petiole) were ground and sieved separately to
produce the filler with particle size ≤ 400µm. Thermal conductivity, thermal diffusivity, and
specific heat capacity were examined using Hot Disk thermal analyses. The acoustic isolation
property examined in a sound-insulated box. The experimental results show that the thermal
conductivity and thermal diffusivity of the composite specimens reinforced by seed or old leaf
bases filler increased with increasing the fillers weight fraction. While increasing the petiole filler
decreased the thermal conductivity and thermal diffusivity by 19% and 40% respectively at 5%
weight fraction as compared with a pure unsaturated polyester material. So, the composite
reinforced with petiole filler has improved the thermal insulation properties. The composites
samples reinforced with palm waste show higher sound absorption in compared to the pure
unsaturated polyester material. The sound absorption properties of composite reinforced with
7% old leaf bases filler improved by 15% and 23% at low and high frequency respectively rather
than of pure unsaturated polyester material.

Enhancing the hydrothermal performance of plate-fin microchannels heat sink (PFMCHS) promises smaller size and lighter weight, and then improve the heat removal in consequently increase
the speed of electronic devices.
In this numerical study, an innovative hydrothermal design of PFMCHS is suggested by inserting
elliptic pins inside microchannels in different; aspect ratio (AR) of pin, pin number ratio (ψ) in
order to optimize the hydrothermal design of this kind of heat sinks. The main objectives of this
study are; investigating the effect of pins on the performance of PFMCHS by investigating the best
geometry in the pinned-fin MCHS and which is higher, thermal or hydraulic performance of this
kind of heat sinks and what is the optimal number of pins numerically and what about the pressure drop penalty in the proposed design, little, modest or high increase.
It is seen that the thermal resistance of the pinned fin MCHS is about 50% lower, and pressure
drop of it is much higher than that of the (PFMCHS) under the condition of equal wind velocity.
Maximum mechanical fan power reduction obtained is about 57% for the pinned fin MCHS with
ψ = 1 and Dh = 1 ×10-3 m compared to the corresponding original channel heat sink. To show the
overall performance of the two parameters; aspect ratio (AR), pin number ratio (ψ), the overall
JF factor is estimated and the concrete findings shows that the best hydrothermal performance
is obtained at the greater aspect ratio which is around overall JF = 1.2. In addition, the trend of
overall JF is going down with the pin number ratio, starting from 1.2 to 1.15. And the concrete
findings show that pinned fin MCHS provides thermal performance of 1.42 times greater than
the smooth one under the corresponding conditions when one pin is used in each channel.

The nonlinear finite element analysis has become an important tool, for the structural design and
assessment of prestressed reinforced concrete members. However, design and assessment of
torsion are still done with simplified analytical or empirical design methods. This paper presents
results from a numerical analysis using the ANSYS finite element program to simulate a prestressed concrete beams subjected to static and cyclic torque. The eight- node brick elements
SOLID65 are used for the idealization of concrete while the reinforcements are idealized by using
3D spar element LINK8. The steel plates are idealized by using three dimensional solid elements
SOLID45. The results showed that the general behavior of the finite element models represented
by torque- twist angle relationships show good agreement with the experimental results from the
Abdullah's beams.

The reducing of heat gain through the outer walls of the buildings in summer will contribute in
reducing the air conditioning costs. This is one of the best features of design requirements nowadays. To achieve this, the phase change materials (PCM) can be used as an embedded material in
the walls to reduce heat transfer. The paraffin wax is one of the common materials used as a PCM
in the building walls. The paraffin wax is used in this study with (20%) volume percentage in the
external layer of the treated wall. In the present work, the treated wall (with embedded wax in
the wall) and non-treated walls have been experimentally investigated. Two Iraqi wall models
were employed to run the experiments, whereby these models were exposed to an external heat
source using (1000 W) projector for each model. The temperatures were recorded at different
locations in the walls during the charging and discharging periods. The results showed that the
temperature of the internal surface for the treated wall was lower than that of the non-treated
wall at the end of the discharging period (6 hr) where the temperature difference between the
treated and non-treated walls was reached (1.6℃).

The demand for strengthening structures becomes necessary when an increase in load is inevitable. For instance very little information is available on the time-dependent behaviour of
strengthened concrete columns. Also, this is a primary factor hindering the widespread uses of
FRP strengthening technologies in the construction implementations. This paper investigates the
behaviour of strengthened concrete columns with FRP sheets subjected to long-term loading by
non linear finite element analysis using ANSYS computer package. A three-dimensional finite element model has been used in this investigation. This study achieved a good agreement between
numerical and experimental results, it was found that the percentage of error of specimens do
not pass (5%) for creep strain. In addition, a parametric study was performed to study the effect
of different factors on the behaviour of FRP strengthened concrete columns

The status of the infrastructure of the transport system and then mobility in the governorate of
Anbar is deplorable. Therefore, it requires two types of solutions in two phases. This study concerned with the first phase, which is represented by solving the problem of the inadequacy infrastructure in terms of availability between the cities, and work to develop it toward being maximally connected. So, generally speaking this study aimed to facilitate mobility through this network, by improving the accessibility in term of connectivity.
The analysis process in this study, have twin objectives: first, to determine how much new linkages we need for our network to be maximally connected as a first stage? Second, Building a
legislative framework lends the weight for decision makers in transport agency to take tough
decision built up on ranking the new proposed linkages according to their relative values in
providing access to the network, and the increment in comparable nodal accessibility due to the
new additions. So, there is need for more sensible decisions based on more accurate analysis for
deciding the optimum priorities for the new linkages to take place in the stage of development
implementation via legislative framework. Therefore, the analysis will deal with topological
characteristics for a number of aspects by expressing the simple graph of the network in a matrix
format. These aspects are simulated and measured through the matrices powering process and
the principles of graph theory.
However, in addition to reducing the time the vehicles stays on the road, the study results will
assist to divert a large proportion of the traffic volumes concurrently with the implementation
process, and this in turn will pave the way to precede the solution of the second phase inside the
cities. Not to mention, the legislative framework will bases for the financial framework of the
transport agency.

Nowadays, renewable energy sources are becoming further utilized to produce electricity.
Fuel cell (FC) is one of the encouraging renewable and sustainable power resources as a
result of its high power density and extremely low release. This paper presents suggestion
and implementation of FC power system. So as to design a greatly efficient FC power system,
proper DC - DC and DC - AC converters are needed. Among the different types of DC - DC
converters, Interleaved Boost Converter (IBC) has been proposed as appropriate interface
between FC and the next stage to transform the produced power energy (low voltage high
current input into a high voltage low current output of the FC). 11-level Neutral Point
Clamped (NPC) Multilevel Converter (MLC) is proposed for converting the DC output of the
IBC to AC voltage to feed the load. MLC is chosen because it has many attractive features like
high voltage capability, smaller or even no output filter, low voltage stress on load. Simulation
of the proposed FC power system has been performed using MATLAB/SIMULINK.