Ansam Ali Hashem Al-Hasnawy
Volume 7, Issue 3 , September 2014, Pages 0-0
Abstract
The objective of this research is to study the effect of Percentage on apparent porosity and compressive strength of ceramic filters. In this research, using ceramic raw materials to produced the filters. Filters made from the raw materials (Sand, Kaolin, and Calcium Carbonate), which obtained from ...
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The objective of this research is to study the effect of Percentage on apparent porosity and compressive strength of ceramic filters. In this research, using ceramic raw materials to produced the filters. Filters made from the raw materials (Sand, Kaolin, and Calcium Carbonate), which obtained from Um Urdhuma and Al- Deuechla in the west of Iraq. Sand was the basic material used to make filters. Selective some of sand particle size (150µm, 125µm, 100µm, 75µm, 50µm), In addition to the binder material that consisted (65% Kaolin + 35% Calcium Carbonate), in different weight percentage (60% Binder + 40% Sand, 50% Binder + 50% Sand, 40% Binder + 60% Sand) ), and used the semidry compaction to forming the laboratory samples
The samples dried in (110 ºC) for (24 hours), and fired or sintered at 1200ºC for soaking time (1hour),then we extracted compressive strength and apparent porosity. The experimental result led to the relationships between (rate of sand, particle size of sand) and apparent porosity and compressive strength of ceramic filter. . Increased the rate of sand increased apparent porosity, but it decreased compressive strength. ). Increased particle size of sand decreased apparent porosity, but it increased compressive strength. The rustles show the maximum apparent porosity (41.328%) at the maximum weight percentage of sand (60%)), and minimum particle size of sand (50µm).The highest compressive strength( 11.831MPa) at lowest weight percentage of sand (40%), and maximum particle size of sand (150µm) .
Basheer Hashem Hlihl
Volume 7, Issue 3 , September 2014, Pages 0-0
Abstract
The object of this paper, is to study the effect of shading and painting the surfaces of buildings on the amount of carbon dioxide emitted into the atmosphere as a result of the consumption of electrical energy used in buildings for air conditioning and thus on global warming for the city of Baghdad. ...
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The object of this paper, is to study the effect of shading and painting the surfaces of buildings on the amount of carbon dioxide emitted into the atmosphere as a result of the consumption of electrical energy used in buildings for air conditioning and thus on global warming for the city of Baghdad. It was found that the effect of an umbrella made of reeds is the largest reduction in the amount of energy used to adapt the built environment and carbon dioxide to the atmosphere arises from the use of white, gray and black surfaces in the months that temperature is greater than 25Co.While there is in addition a larger amount of energy used to adapt the built environment and carbon dioxide to the atmosphere arises from the use of painted surface with color white, gray and black in the months that the temperature is less than 25Co. It has been found that lifting of an umbrella in the months that the temperature is less than 25Co improves performances of surfaces shaded and makes it better than the surfaces with white paint and nearly performance of surfaces with black color and thus reduces the consumption of electric power used in the air conditioning of building and carbon dioxide into the atmosphere and less effects of global warming
Omar H. Kharofa
Volume 7, Issue 3 , September 2014, Pages 0-0
Abstract
The current research tries to focus on the form of relation between the existing policies of the urban renewal and the possibility of their influence by the sustainability methodology which became today in the front of the propounding solutions for most of the adopted directions in the (urban, environmental) ...
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The current research tries to focus on the form of relation between the existing policies of the urban renewal and the possibility of their influence by the sustainability methodology which became today in the front of the propounding solutions for most of the adopted directions in the (urban, environmental) design, through that, choosing a sample for a traditional city is in need to such policies represent a suitable status for the study, city of old Mosul is considered a good example for this purpose for having the past features with all its different faltering and accumulations, where demolition hoes began to snort in its vibrant body.
The current research dealt with unclearness of the relation between the urban renewal policies and the propounding methods of sustainability and the influence of these policies with the current methods, and it tried to explain this relation where it displayed the most important urban renewal policies and analyzing their relation with sustainability methods on the urban level through showing a number of vocabularies within this side and its showing for a relation between each other.
Mohsin Noori Hamzah
Volume 7, Issue 3 , September 2014, Pages 239-253
Abstract
In this paper, the contribution and constitutive modelling of the intercostal muscles (ICM) in a computational thorax FE model is studied. This helps in improving our knowledge to predict the number and locations of the fractured ribs during automotive accidents. ICM demonstrates a number of complex ...
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In this paper, the contribution and constitutive modelling of the intercostal muscles (ICM) in a computational thorax FE model is studied. This helps in improving our knowledge to predict the number and locations of the fractured ribs during automotive accidents. ICM demonstrates a number of complex features including nonlinearity, viscoelasticity, and anisotropy. These muscles consist of an external and an internal layer, each of them having its own fiber orientation.
Tensile tests were performed on ICM samples harvested from one cadaver. Each specimen consisted of a 15 mm-long rectangle of ICM connected to the adjacent superior and inferior sections of the ribs. The load and applied displacement were measured. An optical system (ARAMIS) was used to measure the strain field on the external layer. Preconditioning, ramp and hold (relaxation), and quasi-static failure tests were performed.
The hyperelastic material parameters were estimated through an optimization process based on the experimental force–displacement curves of the quasi-static tensile tests. The results of the parameters optimization revealed that the ICM exhibited a high degree of anisotropy. The identification of the viscoelastic parameters was accomplished from the ramp and hold (relaxation) tests using Prony series.
Muhanad Hamed Mosa
Volume 7, Issue 3 , September 2014, Pages 254-264
Abstract
Fatigue crack growth (FCG) in structures subjected to variable amplitude (VA) loading is a complex phenomenon. Analysing of FCG rate is important for the reliable life of engineering structures. It is difficult to model all the parameters influence FCG correctly due to the random nature of the VA loading ...
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Fatigue crack growth (FCG) in structures subjected to variable amplitude (VA) loading is a complex phenomenon. Analysing of FCG rate is important for the reliable life of engineering structures. It is difficult to model all the parameters influence FCG correctly due to the random nature of the VA loading as well as the number and complexity of the mechanisms involved in the FCG problems. . It has been found from the literature review that no universal model has been developed to analyse the crack growth condition under VA loading. In addition, no general understanding has also been agreed among researchers for any available models. Therefore, the main objective of this work is to investigate the FCG under VA loading based on FCG models also to propose a suitable model for VA loading. The work describes some of the FCG models for predicting the fatigue lives and FCG rates. For the simulation part of this study, towards prediction of crack propagation under cyclic, variable and random loading were used. The results had been carried out based on the Austen, modified Forman and NASGRO models. There are many factors affecting the FCG, which shown with great influence such as; initial crack length, load sequence, aspect ratio and stress ratio.
Abdul Wahab Ahmed Daud
Volume 7, Issue 3 , September 2014, Pages 265-272
Abstract
This research is devoted to study the effect of ball milling technique to improve the surface hardness of carbon steel (CK 45) die guides. This process depends on a rotating cylinder with number of certain size steel balls. Experimental works are carried out on guides rods with (15 mm) diameter, and ...
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This research is devoted to study the effect of ball milling technique to improve the surface hardness of carbon steel (CK 45) die guides. This process depends on a rotating cylinder with number of certain size steel balls. Experimental works are carried out on guides rods with (15 mm) diameter, and (35 mm) length processed on laboratory ball mill. The factors those studied in this process are rotating speed, and time. The surface hardness is recorded before and after the processing. The results show that the best surface hardness is (86.11 Hv) obtained with ball size (5 mm) diameter rotate with (30 rpm) for (90 min.) processing time.
Mr. Alaa Hassoon; Jalal Al-Obaedi
Volume 7, Issue 3 , September 2014, Pages 273-277
Abstract
The use of recycled “reclaimed” materials has been increased during the last decades in order to obtain environmental benefits and to reduce the pressure on natural material resources. This paper focuses on using recycled concrete as a subbase material for highways. Concrete cubes produced from ...
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The use of recycled “reclaimed” materials has been increased during the last decades in order to obtain environmental benefits and to reduce the pressure on natural material resources. This paper focuses on using recycled concrete as a subbase material for highways. Concrete cubes produced from concrete tests such as compression strength, have been crushed to produce different particle sizes so as to satisfy the gradations requirements according to the Iraqi specifications for subbase martial. These recycled samples as well as the samples obtained from ordinary subbase have been subjected to maximum dry density, California bearing ratio (CBR) and Atterberg limits tests.
The results obtained from maximum dry density test suggested that the waste materials could be compacted to reach reasonable density. The CBR test’s results suggest that the CBR values obtained from recycled concrete is significantly higher than those CBR values obtained from the ordinary subbase. The Atterberg tests showed that the waste concrete material is satisfying Iraqi specifications for roads and bridges (SORB).
Hakim Tarteeb Kadhim
Volume 7, Issue 3 , September 2014, Pages 278-289
Abstract
The analysis of the two dimensional subsonic flow over a National Advisory Committee for Aeronautics (NACA) 0015 airfoil at two angles of attack, (α= 0°, α= 16°) and operating at a Reynolds number of 4.4 x 105 is presented. The flow was obtained by solving the steady-state governing equations of ...
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The analysis of the two dimensional subsonic flow over a National Advisory Committee for Aeronautics (NACA) 0015 airfoil at two angles of attack, (α= 0°, α= 16°) and operating at a Reynolds number of 4.4 x 105 is presented. The flow was obtained by solving the steady-state governing equations of continuity and momentum conservation combined with one of three turbulence models [Spalart-Allmaras, Realizable and shear stress transport (SST)] aiming to the validation of these models through the comparison of the predictions and the free field experimental measurements for the selected airfoil. The aim of the work was to show the behavior of the airfoil at these conditions and to establish a verified solution method. Attention is focused on determination of the pressure distribution around the airfoil. Simulations were performed on an map quadratic structured grid with the Fluent (V6.3) software package which solves the Navier–Stokes equations by using finite volume methods. Calculations were done for constant air velocity altering only the angle of attack for every turbulence model tested. Calculations showed that the turbulence models used in commercial CFD codes do not give yet accurate results at high angles of attack and show that the Realizable k- model gave the most closness prediction of pressure distribution when compared with the experimental data [1].
Shatha S. Abdulla Al-Kubragyi
Volume 7, Issue 3 , September 2014, Pages 290-305
Abstract
This paper presents a study of static synchronous compensator (STATCOM). One of the Flexible AC Transmission System (FACTS) devices, it can significantly improve power systems stability. Consisting of voltage sourced converters connected to an energy storage device on one side and to the power system ...
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This paper presents a study of static synchronous compensator (STATCOM). One of the Flexible AC Transmission System (FACTS) devices, it can significantly improve power systems stability. Consisting of voltage sourced converters connected to an energy storage device on one side and to the power system on the other, it specifically can provide reactive support to buses.
This work presents a simple algorithm for identifying weak buses to determine the best location for STATCOM. Singularity of the power flow Jacobian matrix as an indicator of steady-state stability has used, the sign of the determinant of the load flow Jacobian was used to determine the system stability, by computing eigenvalues, eigenvectors , minimum singular value of load-flow Jacobian Matrix and sensitivity analysis between power flow and bus voltage changes.
Load flow analysis of the Iraqi grid 400 KV network has been carried out using Newton- Rephson Method with and without STATCOM. The result of Load flow analysis show improvement in bus voltage with the use of STATCOM in the system.
