bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Opening on Load Carrying Capacity of Reinforced Concrete Slabs: Analytical Study
Authors: Hadi Waleed Khalid , Muttashar Majid 
Published: August 2020

AbstractMost often cut an opening/s in existing concrete slab is essential because of late design requirements. The shape and size of the openings should be chose carefully. While experimental investigation and finite element analysis are difficult to conduct by field engineers, developing a simplified analytical method is important. This study presents an analytical method to examine the effect of opening on the area load capacity of square and rectangular slabs. Two factors were involved in the analysis to take in the account the shape of the slab and the opening. The aspect ratio between the long and short dimensions of slab mentioned by the variable (β), while the aspect ratio between the dimensions of opening is mentioned by the variable (α). The results show that openings have a significant effect on the area load capacity of concrete slabs. In addition, square openings have less effect on the load capacity of rectangular slabs, whereas, rectangular openings have a significant effect on the area load capacity of square slabs. Field engineers can use the presented equations in this study easily and effectively where an opening is required in an existing slab.
Crashworthiness behavior of aircraft sandwich structure with honeycomb core under bending load.
Authors: Sadiq S E , Bakhy S H , Jweeg M J 
Published: August 2020

Abstract
Sandwich structures have been widely used as lightweight composite parts in the aerospace and shipbuilding engineering for their high capacity of stiffness, strength and energy absorption. There are three different criteria in bending crashworthiness for sandwich structure, namely peak bending load, maximum deflection and energy absorption. In this paper, the crashworthiness criteria of sandwich structure were evaluated theoretically and numerically based on failure mode maps. A failure mode map for the loading under three-point bending was constructed, depicting the reliance of the failure mode and the load upon the ratio of the skin thickness to the span length and the relative density of honeycomb. The finite element models for the sandwich panel with a honeycomb core were developed and analyzed via Ansys soft-ware package. The obtained result elucidated a good agreement between these models and the theoretical solution, where the error ratio was not exceeded 5%.To explore the effect of honeycomb parameters on the crashworthiness criteria of sandwich structure, several parameters have been selected, including the core height, the size of cell and the thickness of cell wall. In order to obtain the optimum solution of crashworthiness, Design of Experiment (DOE) software with the technique of Response Surface Methodology (RSM) was used. Results showed that the optimum value of peak bending load (25310 N) as maximum, deflection as minimum (0.8976 mm) and energy absorption as maximum (9.9949 J) were found at 29.2424 mm core height, 5 mm cell size and 1 mm cell wall thickness. Finally, the present study provides a new basis for more studies upon the optimization of the crashworthiness of sandwich structures.
Path Planning Optimization of a Mobile Robot based on Intelligence Algorithm
Authors: Abaas Tahseen Fadhel , Shabeeb Alaa Hassan 
Published: August 2020

Abstract
Motion planning is an important topic for researchers working in the field of autonomous robots, it finds an optimal feasible path from start to target point with avoiding the collision, this paper aims to improve motion planning of mobile robot by particle swarm optimization as a method for finding the collision-free optimal path. The objectives considered in this research for optimization are optimal static navigation path with taking into consideration the affect population size on performance for the algorithm to find the optimal path through various environments with population sizes 100, 80, 40, 20. The simulate and evaluate the proposed algorithm proved no strong affected to population size parameter on the optimal path length and its points, hence we can use a small population size for the minimum time in finding the optimal path between start point to goal point with colliding avoidance.
Experimental and numerical investigations for turbulent air flow characteristics of circular orifice plate
Authors: Abed N , Hassan H F , Al-Damook Amer , Khalil W H 
Published: August 2020

Abstract
The present work describes the airflow characteristics upstream and downstream of the circular orifice numerically using the standard k-ε model and RSM and experimentally employing hot-wire and Pitot tube devices to measure the flow velocities through a tube. An expectation has to bear in mind; the RSM performed well and predicted results in a good level of agreement against the experimental measurements found in preceding studies and the present experimental data as well. In terms of flow physics point of view, velocity and turbulent kinetic energy distribution are presented. Moreover, turbulent viscosity, Reynolds stresses (u2, v2, w2) are also considered. Furthermore, the contours of velocity, static pressure and turbulent kinetic energy are presented beside the wall shear stress and y+ profiles are illustrated to show the flow physics as well as to compare the results of two different turbulence models considered in this study employing Reynolds of 30000 and the ratio of orifice diameter to the pipe diameter of 0.5.
Analysis of Forming Complex Cup by Drawing Process
Authors: Mohammed Adnan I. 
Published: August 2020

AbstractThis paper aims to design and construct a deep drawing dies to produce a complex cup with eight vertices with the major diameter (41.5 mm) and the minor diameter (34.96 mm) and length (30 mm) using numerical simulation and experimental. Also, intended to study the influence of forming method on drawing load, distribution of thickness, and distribution of stress and strain along the wall of the cup were investigated. Two forming methods were used to accomplish this research. The first forming method, which is called the direct forming method in which the complex shape is performed by drawing the circular blank metal. The second forming method is called the converting method, in which the cylindrical cup is redrawn into a complex cup. The low carbon steel sheets (1008-AISI) of the thickness (0.7 mm) and diameter (80 mm) were utilized in this research. ANSYS Workbench 18.0 software in 3-D modeling was utilized to simulate the drawing processes. The results appear that the maximum punch load was with the first forming method (the complex cup is done by drawing the circular blank metal) and higher than the maximum punch load that occurred with the second forming method. The maximum thinning at cup curvature was subjected to the complex cup produced by the first method, especially in areas of convex and concave and more than the complex cups produced by the second forming method. The second forming method is the best method to produce a complex cup with the less thinning at cup curvature and more regular thickness, stress, and strains distribution.
Evaluation of Using the Ceiling and Wall Spots Ventilation System on Indoor Thermal Environment
Authors: Al-Shohani Wisam A. M. , Ahmed Ahmed Qasim , Khaleel Ahmed Jawad , Dakkama Hassan J. , Fayyad Tareq Hamid 
Published: August 2020

AbstractThe aim of this paper is to enhance the local comfortable zone for the occupants in a small office room. The ceiling spot ventilation (CSV) system and the wall spot ventilation (WSV) system are proposed and investigated numerically to show the influence of these systems on the local thermal comfort and energy demand. Three different amounts of airflow rate are used in this investigation. A CFD model is employed to explain the behavior of indoor airflow and temperature distribution in each case study. The results show that, when using these systems as a main ventilation system will reduced the demand on fresh air and this will reduce the required load on cooling coil and saving more energy. Also, the results revealed that the wall spot ventilation (WSV) was provided a required local indoor thermal environment air for the occupant zone. Therefore, using this system will provide a comfortable local environment and enhance the air velocity distribution as well as saving more energy.
Microstructure and phase analysis of brazing bonds for stainless steel (AISI 316L and 431) to carbon steel (A516 G70) using a Ni–Si–B filler metal alloy
Authors: Ahmed Moussa A. , Hashim Fadhil A. , Al-Mohaisen Abdul Mohsin N. 
Published: August 2020

Abstract
Investigation the mechanism of brazing stainless steels (Austenitic stainless steel type 316L and martensitic stainless steel type 431) similar and dissimilar and also brazing them with carbon steel type A516 grade 70 to see the difference in bonding phases, the five specimen were brazed with Ni base filler metal with (4.5% Si and 3.2% B) using a furnace with protected gas (pure Argon) at constant holding time 10 min. The optical and scanning electron microscopy (SEM) are used to study the joint microstructure, also the interdiffusion of the elements was examined by energy dispersive spectroscopy analysis (EDS). While the reaction phases are identified by x-ray diffraction (XRD). The brazed joints showed continuous bonding between the filler alloy and the substrate, indicating to good wetting between the surfaces. EDS line and mapping scan shows The Nickel element which it’s at the filler metal alloy will be goes into the interface almost, because the stainless steels sides can handle it, also Cr element. While Si element will concentrate at the bond zone, finally Fe element Transfer through brazing zones easy. XRD test reveals that the bonding zone of the five specimen shows more the six types of phases which are Ni-Cr-Fe, Cr-Ni-Fe-C, SiC, Fe2B, Cr2B, and Cr-Fe-Ni-Mo.
Effect of sliver filler metal alloy on bonding structure for brazing Ni270 to Ductile cast iron
Authors: Looty Abbas F. , Hashim Fadhil A. , Hussein S K 
Published: August 2020

Abstract
Diffusion brazing mechanism of two dissimilar alloys Ni 270 and Ductile cast iron(DCI) by BAg-5 and BAg-7 filler metal with bonding time of 10 min was investigated. Shear strength test was performed to evaluate mechanical properties. The bonding phase for joining side nickel by using the two type of filler metal alloy BAg-5 and BAg-7 is the NiCu phase with shear strength about 70 Mpa, and the bonding phase for joining side ductile cast iron by using the two type of filler metal alloy BAg-5 and BAg-7 is the Fe3Si and SiC phase with shear strength about 40 Mpa. The joining of nickel 270 plate and ductile cast iron by using BAg-5 filler metal alloy shows an Eutectic structure at the middle of filler zone, which lead to great affinity between nickel element with copper. The optimum shear strength of 43 MPa was achieved for the bond made by BAg-7 filler metal.
Iraqi gasoline performance at low engine speeds
Authors: Allawi Mohammed Kadhim , Mejbel Mohanad Kadhim , Oudah Mahmood Hasan 
Published: August 2020

Abstract
Four grades of gasoline fuel – obtained from Iraqi oil refineries – are used in this research to investigate their performance in spark-ignition (SI) engines. These grades are RON 77, RON 82, RON 87, and RON 93. We used a four-stroke, four-cylinder SI engine laboratory rig to conduct the experiments and calculate the engine performance for each gasoline grade. We compared the experimental results with the predicted numerical simulations carried out using a well-known commercial software called Lotus Engine Simulation (LES). The numerical results obtained using LES show good agreement with experimental findings. A higher gasoline grade shows better engine performance than lower grades owing to its superior quality and purity, better combustion characteristics and performance, and lower amount of gasoline inclusions. Gasoline fuel RON 93 provided the best engine performance in comparison to the remaining grades. The variation between the numerical and experimental results in all tested conditions was below 3%.
Joining of Aluminium Alloy AA6061-T6 to PVC Polymer by Friction Stir Lap joining Process
Authors: Mohammed K A , Hussein S K , Khuder A H 
Published: August 2020

Abstract
The aim of this research is to join sheets of aluminium alloy AA6061-T6 of 1.5 mm thickness with polymer polyvinyl chloride (PVC) of 4 mm thickness by a friction lap technique. Drill holes of 3, 4 and 5 mm were produced in the AA6061 specimens and a lap joint arrangement was set up with the PVC sheet. Six parameters were used in this technique: hole diameter, tool diameter, number of holes, rotating speed, linear speed, and tool plunging depth. The shear test results at the holes were analyzed by a Minitab program with the aid of the Taguchi method. IR thermometer was used to measure the temperature distribution at the joint. The results indicated that all the samples failed with shearing the PVC at the aluminium hole without dislocation the polymer. The maximum shear force is 1850N. The joint shear force increased by increasing the plunging depth and rotation speed of the tool and decreased by increasing the hole numbers and diameter of the aluminium specimen. The hole diameter beside the rotating and the linear speed exhibited the highest effect on the joint shear strength. The developed temperature during the joining process was an effective parameter on the joints quality. The SEM tests indicated that the joining between the aluminium and polymers occurred by a mechanical interlocking at the common surfaces.
Effect of Heat Treatment on Toughness and Fatigue Behavior Strength of Steel CK45
Authors: Ibrahim Al-Zuhairi Haitham M , Hamza Asaad Khudhair , Mahdi Bahaa Sami , Al-Alkawi Hussain J M 
Published: August 2020

Abstract
The function of the axle drive shaft is to transfer the engine torque from the gearbox or differential gear to the wheels. It must also endure for all dynamic loads resulted from variations in angle or length during driving from contact the vehicle tire with road. Most problems with the axle drive shaft manifest themselves in the form of knocking noises when driving around tight corners, accelerating, or when the suspension is being compressed and extended where the drive shaft becomes weakened and more subject to stress failure due to dynamic torsion, tensile, shear, and compression. This work consists of effect of heat treatment type applied to the steels CK45 on the resulted behavior of the fatigue and toughness and study of these heat treatments on the microstructure and micro-hardness across the specimens depth. Where this heat treatable alloy usually used in drive-shafts in vehicles which exposed to a dynamic loads and the goal is to investigate the best relation between heat treatment and the service conditions. However, microstructural characterization and microhardness measurements revealed that the shaft belongs to medium carbon steel contains ferrite and pearlite, measuring the toughness for four heat treatments to obtain the best case and measuring the fatigue life of quenching case has better life compared to other cases. The oil quenching gives best toughness value of 30 Kj/m2 and the worst value obtained for as received one giving 7 Kj/m2 and the maximum fatigue life under stress of 375 MPa belonged to oil quenching treatment and it was 75000 cycles to failure while the as-received alloy reported 2000 cycles at failure. The S-N curve of the four cases based on Basquin formula with correlation factor (R2) close to one. And the water quenching steel alloy recorded higher curve component to other cases.
Numerical stress analysis for single-lap adhesive joint under thermo-mechanical load using non-linear material
Authors: Al-Ramahi Nawres J , Joffe Roberts , Varna Janis 
Published: August 2020

Abstract
A comprehensive stress analysis by means of Finite Element Method (FEM) for single-lap joint subjected to thermal and mechanical loads is presented in this paper. Simulation is used to predict the effect of residual thermal stresses (caused by difference of temperature of use and elevated temperature during the assembly of the joint) on stress distribution within adhesive layer. The residual thermal stresses are assigned to joint members as initial condition before the mechanical load is applied. The FEM model employs linear and nonlinear material model and accounts for geometrical nonlinearity. It is confirmed that the difference between the manufacturing and the ambient temperature results in high residual thermal stresses, especially in axial and lateral directions of the joint. The calculation of total stress as superposition of thermal and mechanical stresses works only for linear materials. Moreover, simultaneous application of temperature and mechanical load (applied strain in case of displacement controlled test) in FEM produces inaccurate results, since in real situation the strain is applied to already thermally loaded structure. It is also found that the residual thermal stresses may reduce the peel and shear stress concentration in the adhesive at the ends of overlap and the shear stress within the overlap.
Experimental Investigation of Hold Time Effect on Springback in V-Bending Sheet Metal Forming Process
Authors: Khleif Ali Abbar , Kashkool Lujain H , Hassoon O H 
Published: August 2020

Abstract
Springback is considering as one of the most common problems in metal forming processes, which poses an inaccuracy of product angle during assembling of parts. The estimation of the springback is difficult to predict for formed parts, since it depends on many factors such as the mechanical properties, the sheet thickness and the die angle. In this work, experimental investigation for different thickness and holding time have been studied and analysed. Samples of (Aluminium, brass, and C1004 Steel) specimens with 80 mm length, 50 mm width and 2, 3 and 6mm of thickness selected in this study. Using bending die with angle value (730 and 900) pulled three pieces of each different holding times. Three pieces for each metals were hold with three times (2, 4, 6 minutes). The results show that in a given thickness configuration, the springback reduced with increasing of the punch hold time for all thicknesses selected.
Investigation of Friction Stir Welding of AA2024-T4 Thin Sheets for Industrial Applications
Authors: Ridha Munaf Hashim , Alkhazraji Sohaib Khlil , Abdullah Isam Tareq 
Published: August 2020

Abstract
The welding of aluminum alloys thin sheets is a complicated process no matter what the technology used. A 2024-T4 AL sheets of 1.2mm thickness were welded using stir welding method and then examined for their mechanical and microstructure characteristics. The process included the use of specifically designed fixture along with cylindrical tool. Thin sheets welding of aluminum alloy is a complicated process either in conventional or newly developed methods. In this approach the friction stirs welding (FSW) is used. Tensile test and microstructure test were conducted to analyze final product properties. The cylindrical rotating tool was used to create a joint which is specifically useful in the welding of aluminum alloys in particular. It was found that All tested samples were defects free. Mechanical properties show that ultimate tensile strength of samples is below the base metal. Two rotational speed were applied (900 and 1400) rpm with welding feed rate of (20, 40 and 80) mm/min respectively. The tool has a 1.2mm diameter pin of 1 mm height and 8mm shoulder diameter. A rotation speed of (900) rpm and feed rate of (40) mm/min gave the best quality product in which an increase of (72%) in ultimate tensile strength was observed.
Mixed Convection Enhancement in a Rectangular Cavity by Triangular Obstacle
Authors: Afluq Shaalan Ghanam , Abas Siba Mohamed Abed Al , Jehhef Kadhum Audaa 
Published: August 2020

Abstract
Numerical modeling analysis of mixed convection heat transfer for air flow in a cavity with bottom local heat source and top inlet and outlet sections is studied. Also, the cavity equipped by vertical triangular obstacle on the top wall in order to enhancement the convection inside the cavity are researched. System of dimensionless stationary Navier-Stokes equations is solved numerically by discretizing the compositional domain into small grids. Mixed convection regimes are the viscous incompressible Newtonian fluid with Reynolds number range (800-1400) and the Grashof number ranged (105-108) and at fixed Prandtl number at (7.1). The pressure, temperature and velocity distributions characterizing the basic laws of viewed process. The results showed that the main circulating currents in different zones of the cavity is due to the effect of number of blocks and the presence vertical triangular obstacle on the top boundary of the cavity. The formation of thermal conditions in the region under study and the effect of low temperatures above the heated bottom wall on the circulation fluid flow in a cavity. Distribution pattern established velocity and temperature profile in centered sections depending on the height of vertical triangular obstacle. Also, the results showed that the Nusselt number increased by about 26% when increasing the height ratio of triangular obstacle to (h/H=0.5) with three blocks.
Evaluation of Green Supply Chain Management Practices Under Uncertainty Environment: Case Study in The Company for Batteries Industry
Authors: Faris Hiam Muhammad , Maan Harith Yarub 
Published: August 2020

Abstract
This work used a model of integrated the fuzzy set theory and Decision-Making Trial and Evaluation Laboratory to evaluate the green practices that can affect the green supply chain implementation in battery industry. The integrated fuzzy MCDM model is used to assess the GSCM performance in company based on green terms: green purchasing, green manufacturing, reverse logistic. Therefore, using fuzzy DEMATEL method to exploring the relationship between criteria and factors which affect other factors in GSCM. The hybrid approach presented an empirical analysis under linguistic preferences for the firm to find the critical practices that affected the GSCM performance and green practice implementation. The results showed that the economic performance and the revers logistic are the cause of the low environmental performance of the company and located in the cause group.