Israa Faisal Qhazi
Volume 10, Issue 2 , June 2017, Pages 120-132
Abstract
This research studied the mechanical properties of particulates composite materials made from natural fillers (eggshell and sawdust) reinforced epoxy resin. The composite specimens were prepared by hand lay-up technique with one volume fraction Vf, and different particle size of fillers.
Modulus of ...
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This research studied the mechanical properties of particulates composite materials made from natural fillers (eggshell and sawdust) reinforced epoxy resin. The composite specimens were prepared by hand lay-up technique with one volume fraction Vf, and different particle size of fillers.
Modulus of elasticity, tensile strength, percentage of elongation and hardness were measured for each type of composite. The tensile tests results had shown an incremental increase with size of particles decreasing also hardness results had shown an incremental increase with smaller particle size.
This work institutes a good substitution for synthetics fillers avoiding their highly cost and their toxicity, at the same time reducing of the environmental pollution.
Anahed Hussein Jebur
Volume 10, Issue 2 , June 2017, Pages 133-146
Abstract
The stress of the helical spring changes with several parameter are studied using (solidworks2014) program. The stress effect is by coil diameter (D) and the shape of section of the helical spring wire (circular ,rectangular and square) for the same diameter, where the stress on the helical spring ...
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The stress of the helical spring changes with several parameter are studied using (solidworks2014) program. The stress effect is by coil diameter (D) and the shape of section of the helical spring wire (circular ,rectangular and square) for the same diameter, where the stress on the helical spring wire increases by increasing the coil diameter (D), also the stress on the helical spring wire affect by changing the shape of the spring wire section
Ahmed Kareem Abdullah
Volume 10, Issue 2 , June 2017, Pages 147-157
Abstract
The swarm techniques are used widly to enhance the response of the control system, but there are many drawbacks appear when these techniques are used to select the initial solution for the problem and then will referect on the overall convergence. This paper try to solve this problem by modify the initial ...
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The swarm techniques are used widly to enhance the response of the control system, but there are many drawbacks appear when these techniques are used to select the initial solution for the problem and then will referect on the overall convergence. This paper try to solve this problem by modify the initial solution of particale swarm techniques based on fast genetic algorithm, the modified PSO make good free searching in candidate solutions to get optimum suggesions, which leads the algorithm towards the global optimum searching over wid range. The proposed controller named PSO-FGA-PID controller and two experiments are tested by this controller to check the proposed work, first one the linear time invariant system is taken and the second one is to control on the speed of the DC motor.
Hassan Fallah Hassan; Mohammed Hussein Al Dahlaki; Mohammed Khachi Hatem
Volume 10, Issue 2 , June 2017, Pages 158-170
Abstract
This study deals with experimental studying of the influence of an adjacent surcharge loads on pile's behavior in both horizontal and sloping ground surface. A number of laboratory tests were performed on instrumented aluminum pipe piles of 25 mm outer diameter embedded in sandy soil subjected to surcharge ...
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This study deals with experimental studying of the influence of an adjacent surcharge loads on pile's behavior in both horizontal and sloping ground surface. A number of laboratory tests were performed on instrumented aluminum pipe piles of 25 mm outer diameter embedded in sandy soil subjected to surcharge load. The study took into consideration the effect of surcharge intensity, sloping ground and soil's relative density on lateral deformation of piles in terms of displacement and bending moment. The study was performed on different sloping ground [vertical to horizontal (V:H)] such as, "1V:3H", "1V:2.5H", "1V:2H" and "1V:1.5H", in addition to horizontal ground. Three different relative densities of sand (29% , 50% and 75%) were adopted in this study. The results showed that the increasing in the surcharge loads increases lateral displacement and bending moments of piles in horizontal and sloping ground surface. It was also calculated that the bending moments and displacement of piles increase with increasing sloping ground and decreasing relative density of soil.
Raad M. Abed; Mohsin N. Hamzah; Shaker S. Hassan
Volume 10, Issue 2 , June 2017, Pages 171-179
Abstract
The ultrasonic peening technique (UP) is one of the innovative and hopeful methods for fatigue life enhancement and upgrading of welded structures and components. The fatigue testing of sheet specimens for 6061-T6 aluminum alloy, demonstrated that the UP is an effective change treatment to mechanical ...
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The ultrasonic peening technique (UP) is one of the innovative and hopeful methods for fatigue life enhancement and upgrading of welded structures and components. The fatigue testing of sheet specimens for 6061-T6 aluminum alloy, demonstrated that the UP is an effective change treatment to mechanical properties as judged against unpeened specimens. S-N curve and the fatigue fracture mechanism were scrutinized in detail. The most important results revealed the fatigue life of specimens improved due to the surface hardening. Residual compressive stresses were created by UP and increased the fatigue life and strength. This paper scrutinized the potential use of ultrasonic waves on the surface of 6061-T6 aluminum alloy. This can be exhibited as a factor of safety due to ultrasonic, reach to 1.42 when estimate the number of cycles fatigue based on amount of applied stress at 0.3 u.
Mostafa Adel Abdullah
Volume 10, Issue 2 , June 2017, Pages 180-190
Abstract
The Bending process is the critical operation in the sheet forming, there are large parameters influence on operation. Spring back is considering large influential indication to specify the quality of product parts. The basic parameters which are takes to study in this paper are: speed of punch, time ...
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The Bending process is the critical operation in the sheet forming, there are large parameters influence on operation. Spring back is considering large influential indication to specify the quality of product parts. The basic parameters which are takes to study in this paper are: speed of punch, time of hold and thickness of plate. Experiment use L16 array with four levels for every parameters using V-bending die with 900, with different thickness of (0.5,1,1.5,2) mm ,hold time (0,5,10,15) min and punch speed(10,20,50,100)mm/min, for (1050) Al –alloy having employed as the work pieces. Spring back value prediction use Artificial Neural Network with conventional configuration. The results show that the thickness of plate is the large influential parameter effect in spring back by 77.29%, then punch speed by 10.51% and hold time by 3.36%. The predict result using Artificial Neural Network shown a best accuracy with (99.35%) in spring back compared to the measured value.
Shamil Ahmed Flamarz Al-Arkawazi
Volume 10, Issue 2 , June 2017, Pages 191-202
Abstract
The operation analysis of isolated signalized intersection provides valuable and important information about the performance of transportation system in the city. The signalized intersections are major elements and critical points within the city transportation network; therefore accurate detailed information ...
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The operation analysis of isolated signalized intersection provides valuable and important information about the performance of transportation system in the city. The signalized intersections are major elements and critical points within the city transportation network; therefore accurate detailed information and data about the capacity and operation performance of the signalized intersections is very important and more significant to evaluate and improve the capacity of the transportation system and network of the city. Highway Capacity Manual (HCM) Model is widely used for operation analysis of the isolated signalized intersections in Iraq through number of traffic analysis software tools which uses the HCM delay model. The most popular and widely used among traffic analysis software tools are; HCS 2010, SIDRA 5.1 and TRANSYT-7F Release 11. The objective of this study is a comparison between these three traffic analysis software tools based on evaluation of the quality of their operation analysis and optimization capabilities of isolated signalized intersections in order to be a good guide for the traffic engineers to decide which of these tools provide better results in evaluating the quality of isolated signalized intersections operation performance and optimizing intersection parameters. To achieve this objective, Bukhari signalized intersection in Kalar City was selected and the required data for the study purposes were collected. Based on results of this study SIDRA 5.1 is the most effective and the richest operation analysis and optimization software among the three selected computer traffic analysis software tools; HCS2010, SIDRA 5.1 and TRANSYT-7F Release 11.
ahmad flayyih hussein; aqeel ali al-attar
Volume 10, Issue 2 , June 2017, Pages 203-213
Abstract
In this work, the porous Magnesium alloy (AZ91 ) was prepared by Space holder technique to deposit carbon nanotubes, Novalac powder was used as space holding and fugitive materials with different particle size (≥20 µm, ≥500 µm) and amount (50, 52, 54, 56, 58, 60%wt.). Impact of Novalac powder (particle ...
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In this work, the porous Magnesium alloy (AZ91 ) was prepared by Space holder technique to deposit carbon nanotubes, Novalac powder was used as space holding and fugitive materials with different particle size (≥20 µm, ≥500 µm) and amount (50, 52, 54, 56, 58, 60%wt.). Impact of Novalac powder (particle size and additive percent) on density and porosity of porous AZ91 alloy was studied. Fine Novalac powder (≥20 µm) not recommended in the porous AZ91 alloy preparation, concurrently coarse Novalac powder (≥500 µm) was suitable for that purpose. It was found that the density of AZ91 alloy decreased with increasing Novalac concentration. Carbon nanotubes were deposited on the porous AZ91 alloy by catalytic chemical vapor deposition whereas NiSO4.6H2O used as catalyst, acetylene gas as a carbon source and argon gas as a carrier gas with flow rate percent 1:1, at 575°C process temperature for 30 min. Multiwall carbon nanotubes were obtained and characterized by X-ray diffraction and scanning electron microscopy techniques. The average diameter of the multi wall carbon nanotubes was (46 nm). Although the porosity percent of AZ91 alloy was not majorly effect proportionally by the increasing of an additive Novalac percent, the yield (quantity) of Multiwall carbon nanotubes was enhancing due to increase the porous AZ91 alloy surface area.
Ammar Y. Ali; Labeeb S. Al-Yassri; Mohammed M. AL-Khafaji
Volume 10, Issue 2 , June 2017, Pages 214-225
Abstract
This paper presents an experimental study to investigate the effect of hybrid strength concrete (two types of concrete, 25 MPa and 70 MPa) on the behavior of one-way hollow core concrete slab ordinary reinforced with steel rebars. The hybrid HCSs showed an enhancement in shear strength capacity, cracking ...
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This paper presents an experimental study to investigate the effect of hybrid strength concrete (two types of concrete, 25 MPa and 70 MPa) on the behavior of one-way hollow core concrete slab ordinary reinforced with steel rebars. The hybrid HCSs showed an enhancement in shear strength capacity, cracking load and ductility as compared with to HCS with normal strength concrete (25 MPa). The increase in shear strength capacity and cracking load were about (16%) and (29%) respectively higher than normal strength hollow core slab. Also, from experimental results, the crack width of hybrid HCS was narrower than that for normal strength slab at all stages of loading. At service load stage, the width of crack was narrower than normal strength slab by about (10-31%). The failure mode still brittle diagonal shear failure.
Qusay Rasheed AL-AMIR
Volume 10, Issue 2 , June 2017, Pages 226-243
Abstract
This paper represents a numerical study of a triple-stage series flow absorption cycle operating with LiBr-H2O pair. A computational model is implemented using Engineering Equation Solver (EES) software. This model includes equations of mass, species and energy conservation. The analysis is used to ...
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This paper represents a numerical study of a triple-stage series flow absorption cycle operating with LiBr-H2O pair. A computational model is implemented using Engineering Equation Solver (EES) software. This model includes equations of mass, species and energy conservation. The analysis is used to simulate a triple stage absorption chiller utilization for an air conditioning applications with a nominal capacity of 300kW manufactured by Thermax company. This chiller is indirect fired type which uses steam from boiler of the HPG as heat source. The variations of performance parameters with different ranges of operation conditions have been calculated. The operating parameters are selected as follows: the HPG, MPG and LPG temperatures: THPG= 150-230°C, TMPG= 100-130°C and TLPG= 60-95°C, respectively, LPC temperature TLPC= 28-37°C, evaporator temperature Tevap = 5-14°C; flow rate of refrigerant mr= 1 kg/s; four values of heat exchangers effectiveness 0.4, 0.5, 0.6 and 0.65. In addition, the comparison between the present study and other study obtained in literature review has been done. The analysis revealed that maximum COP is found as a function of both MPG and LPG temperatures. The results outline that the COP increases with an increase in the evaporator and generators temperature but decreases with condenser temperature.
