Print ISSN: 1814-6120

Online ISSN: 2311-8385

Volume 17, Issue 1

Volume 17, Issue 1, Spring 2017, Page 1-83

Comparison of multicarrier PWM techniques for nine-level inverter drive an open-end winding induction motor

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 1-11

Different modulation techniques of Nine-Level
Inverter (NLI) for an Open-End Winding Induction Motor
(OEWIM) is presented in this paper. The two five-level
inverters are fed by both ends of the open-winding induction
motor. The five-level inverters are connected by cascading of
four two-level inverters. This inverter topology does not
neutral-point fluctuation so this topology different from
neutral-point clamping inverter and this scheme does not the
diode clamping to a fixed neutral point. In the different
multilevel sinusoidal pulse width modulations used for the
proposed topology. The drive is implemented and simulation
with an open-end winding induction motor and simulation
results are presented

Crack Growth Simulation in Corrugated Plate Using XFEM

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 12-15

Corrugated plates play an important role in many
modern constructions applications. Being the main components
like piles or stiffeners means they quite often subjected to high
levels of stresses. The presence of flaw or crack in the structure
of loaded corrugated plate may lead to the situation of crack
growth and then catastrophic failure. Extended Finite Element
Method is used to avoid remeshing during crack growth
simulation. In order to characterize crack growth in a corrugated plate, two methods were used which are virtual
crack closure method and cohesive segments method. Two case
studies were investigated in this study. In the first case, the
material behavior is assumed to be linear elastic, while in the
second one the material behavior is assumed to be elastic-plastic.
The results obtained using the two methods showed a very
good agreement both in linear elastic and elastic-plastic cases.

A Chaotic Crow Search Algorithm for High-Dimensional Optimization Problems

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 16-25

Crow Search Algorithm is an innovative metaheuristic optimization algorithm. In this paper, chaotic maps
are combined into Crow Search Algorithm to increase its
global optimization. Ten variant chaotic maps are used and the
Tent map is found as the best choices for high dimensional
problems. The novel Chaotic Crow Search Algorithm is relied
on the substitution of a random location of search space and
the awareness parameter of crow with chaotic sequences. The
results show that the chaotic maps are able to enhance the
performance of the Crow Search Algorithm. Also the novel
Chaotic Crow Search Algorithm outperforms the conventional
Crow Search Algorithm, the first version of Chaotic Crow Search
The algorithm, Genetic Algorithm, and Particle Swarm
Optimization Algorithm from the point of view of the speed
convergence and the function dimensions

Energy and Exergy Analysis of Rumaila-Basra Gas Turbine Power Plant During Hot Sea

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 26-34

In this paper, energy and exergy concepts have been
carried out on one of the largest gas turbine power plants in
Iraq (Rumaila-Basra). Both ISO operating conditions as well
as actual operating data recorded for one month in hot season
are considered. Results indicate that a lot of heat energy
accompanied with remarkable exergy is discharged to the
atmosphere. Also, it is found that the combustion chamber has
the largest exergy destruction among the plant components.
The possibility of cooling the intake air drawn by the compressor
and its effects on the plant performance is studied. The
required cooling load is found to be in the range 3379 T.R for
part load operation to 4723.3 T.R for full load operation

Energy-Exergy Performance Comparison of an Ideal Vapor Compression Refrigeration Cycle using Alternatives Refrigerants of R134a for Low Potential of Global Warming

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 35-39

This work presents a theoretical study on the
application of low global warming refrigerants as an alternative
refrigerant to R 134a in a refrigeration system. The
refrigerants investigated are R1234yf, R1234ze, R245fa and
R227ea. The performance characteristics of the refrigeration
system were predicted using mathematical models running by
using EES program under different condenser and evaporator
temperatures. The results show that at any working condition
the R1234ze give an identical performance to R134a and can be
used as the best low global warming alternative refrigerant. So
the compressor work with R1234ze should be designed with
displacement volume more than that of R134a to overcome the
reduction in mass flow rate

Fast Combined Decimal/Binary Multiplier Based on Redundant BCD 4221-8421Digit Recoding

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 40-47

Many applications consider floating point arithmetic
as a key component of the computations. Combined
decimal/binary arithmetic becomes an important topic
supports high-speed decimal/binary applications. A new 64-bit
(16×16 digit) the combined decimal/binary multiplier is proposed
and implemented in this work that can be used for both fused
multiply-add (FMA) and multiplier unit. A new partial
products reduction tree is shared between decimal and binary
multiplier unit. The valuation and comparison result between
the proposed multiplier and the previous most recent works
shows 4.66 % less delay than combined decimal/binary
multiplier and 19.33 % less delay than the fastest standalone
decimal multiplier

Gypsum Content Horizontal and Vertical Distribution of An-Najaf and Al-Kufa Cities' Soil by Using GIS

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 48-60

An-Najaf province considered one of the most
important cities in Iraq, which is facing rapid population
growth and continuous development in constructions such as
housing, hotels, bridges and shopping malls. Therefore, this
study aims to create a database for the gypsum content in AnNajaf province (Najaf center and Al-Kufa city). To evaluate
the spatial variability of gypsum content, 464 boreholes and in
situ tests were selected and analyzed using Geographic
Information System (GIS). To achieve that, the adopted
method consisted of four steps: (1) data collection; (2)
geotechnical data georeferencing; (3) interpolation methods
and (4) establishment of maps. Nine geotechnical maps were
produced for depths (0, 2, 4, 6, 8, 10, 12, 14, 16, and 35) m.
Results showed that the largest part of the study area for the
depths from 0-4 m had a gypsum content ranged between 10-
25% (moderately gypsiferous), whereas the depths from 4-8 m
had a gypsum content ranged between 3-10% (slightly
gypsiferous), and the depths from 8-35 m had a gypsum
content ranged between 0.3-3% (very slightly gypsiferous).
This concludes that the layers from 0-4 m are exceeding the
allowed limits (10% gypsum content), which may affect the
stability of constructions due to the high levels of groundwater
in Najaf province

IoT Based Intelligent Greenhouse Monitoring and Control System

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 61-69

Recently, the Internet of Thing technology has been used
to develop numerous applications, this paper compromising
design and implementation of greenhouse prototype that
integrated with the IoT to adjust the system’s parameters and
monitor the system status from any place in this world.
This system involves three intelligent controllers that designed
to stabilize the temperature degree, the water level in the soil, and
light intensity inside the greenhouse prototype structure. These
systems have been built by two important parts: the hardware
and software.
The hardware part could be achieved by designing and
implementing the control circuits, actuators, and install the
sensors as well as the devices. The second one is the software
the part which is involves implementing Fuzzy Inference Engine
that represent the system’s brain that monitor and manage the
entire process in the system to ensure the best performance.
This system has been built to contain three control systems that
means there are three different Fuzzy controllers. In order to
keep the system practicality, the fuzzy controllers should be
aggregated in single code that resides in single microcontroller
chip with additional codes that perform the IoT duties.
The proposed IoT system provides the ability for specific
people to monitor and manage their systems remotely, using a
web application with cloud technology.
The major contributions of the proposed system are started by
downloading the controller’s set-points (the desired
environmental conditions) from the web page, transfer the setpoints to the controllers, and upload data that read from
sensors to the same web page.)

Neuro-Fuzzy Network Based Adaptive Tracking Controller for a Nonlinear System

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 70-75

In this paper, a neuro-fuzzy network-based adaptive
tracking controller is suggested for controlling a type of
nonlinear system. Where two neuro-fuzzy networks have been
used to learn the system dynamics uncertainty bounds by using
Lyapunov method. Then the output of these two networks is
used to build a sliding mode controller. The stability of the
control system is proved and stable neuro-fuzzy controller
parameters adjustment laws are selected using Lyapunov
theory. The simulation case study shows that the controlled system
tracking the reference model effectively with smooth control
effort and robust performance has been achieved

Sensitivity Analysis and Simulation of TEG Dehydration Unit in Central Rumaila Compression Station in Basrah-Iraq

Basrah Journal for Engineering Science, Volume 17, Issue 1, Pages 76-83

In the operating of TEG- dehydration unit in Central
Rumaila Compression Station. Two operating parameters
determine the efficient operating of the unit, the desired dew
point depression and the losses of TEG. This work presents an
attempt to study the effect of all the operating variables on the
efficiency of the dehydration unit such as the effect of pressure
and temperature of the natural gas has to be treated on the
water content. Contactor pressure, TEG circulating rate and
stripping gas flow rate are also considered in this study. The
results showed that decreasing the temperature of the absorber
from 130 F to 120 F will reduce the mass fraction of water in
the dry gas stream from 0.000076 to 0.00002. Increasing the
absorber pressure from 549.7 psia (design pressure) to 600 psia
will also reduce the water content in the outlet dry gas from
0.000076 to 0.000022 as a mass fraction. The simulation result
shows a linear relationship between the wet gas flow rate from the
regeneration column and the lean glycol flow rate.