bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of external helical ribs tube on the heat transfer and pressure drop performance for multi - tube heat exchanger
Authors: Talib Ruaa N. , Yasin Nabil J. , Nasser Mohammed A. 
Published: June 2019

Abstract
The pressure drop and heat transfer characteristic for cross flow of turbulent air over helical rectangular ribs tubes heat exchanger were studied experimentally and numerically. The study includes the design and manufacturing of four models of multi-tube heat exchangers. Each model has three tubes in a line arrangement. Experiments were performed for Reynolds number range from (7200–31400) using different rib pitch to diameter ratios (P/D = 1.3, 1.5 and 1.8) with different ribs pitch angles. The height to diameter ratio of rib (h/D = 0.05) and width to diameter ratio is (w/D = 2) were fixed. The water flows with different rates inside the tubes with a range of (2, 3, 4, 5, 6 and 7) L/min. Three values for the inlet water temperatures to test tube were used. In the present numerical part, commercial software ANSYS Fluent 16.2 was employed to determine the heat transfer coefficient and pressure drop for the different models of cross flow heat exchangers. The results declared that the average Nusselt number and Pressure drop of the corrugated model has a relatively high different from that of the smooth models. In addition, the experimental and numerical were compared and gave a good agreement between them.
Effect of Shot Peening and Solidification on Fatigue Properties of Epoxy Base Composite Material
Authors: Abdul-Kareem Hamza Salah , Abdulla Fadhel Abbas , Abdulrazzaq Mohammed Abdulraoof 
Published: June 2019

AbstractThis work evaluated experimentally the fatigue stress behavior of two types of composite material (SIR-epoxy resin with woven E-glass fiber as reinforcement and SIR-epoxy resin with random E-glass fiber as reinforcement) subjected to shot peening (2, 4 and 6 min) through three different times of solidification of samples (two, four and six days). The results show that, for woven reinforced composite, the great improvement in fatigue stress was obtained at both two and six days of solidification with (2, 4 and 6) min of shot peening times (SPTs) in which the percentage of the maximum enhancement was 59.38% in fatigue stress (at two days of solidification and 6 min shot peening time). For random reinforced composite the great improvement of fatigue stress was obtained at two and six days of solidification with (2, 4 and 6) min of shot peening times (SPTs) in which the percentage of the maximum enhancement was 33.78% (at two days solidification and 6 min shot peening). After four days of solidification, increasing shot peening time will decrease the fatigue stress for both types of composite materials (woven reinforcement and random reinforcement) and the maximum decreases in fatigue stresses at 6 min of shot peening was -43.06% and -28.9% for woven composite and random composite respectively. The tensile test and the fatigue test were done after full solidification of all the patterns.
Hybrid Analytical Hierarchy Process and Continuous Improvement Methodology to Enhance Sustainability: A Case Study on a Beverages Industry
Authors: Ibrahim Mohammed Jalil , Mahdy Hussein F. , Jailawi Roaya M. , Kassir May George , Dawood Lamyaa Mohammed 
Published: June 2019

Abstract
Aims of sustainability in the industries are to create manufactured products, which use processes and practices that maximize profits, reduce waste, minimize resource use, minimize negative economic and environmental impacts, and are safe for consumers and employees. These aims can achieve through continuous improvement methodologies (CI). Therefore, CI have emerged as a major part of the sustainability answer. The purpose of this research is to investigate the application of hybrid methodology consist of analytical hierarchy process (AHP) and continuous improvement methodology in the beverages industry, and to evaluate the impact of this methodology on sustainability. The proposed methodology framework consists of five steps (Identity, Measure, Analyze, Prioritize, and Implement). This research highlights some of the important elements that should be considered when using AHP and CI as a contributor toward greater environmental sustainability in the beverages industry. The results show that the main causes of waste relate to machines, materials and others cause. This paper present observations and experiences from the application of AHP and CI at a beverages industry, with the aim of bringing out pertinent factors and useful insights that help us to understand how AHP and CI can contribute toward greater sustainability in this industry type.
Engine performance and emission formation of a diesel engine fueled with biodiesel B15 at different injection timings
Authors: Aldhaidhawi M , Najee M , Mahboba Mohammad Hmid 
Published: June 2019

Abstract
Biodiesel could now be considered as an alternative fuel for compression ignition engines and it can be used directly or in blends with diesel without engine modification. Biodiesel is non-toxic, contains no aromatics is sulphur-free, biodegradable and an oxygenated and renewable fuel. In the present work, a numerical study was performed to determine the engine performance and exhaust gas emissions of a direct injection DI, four-cylinder, diesel engine by using pure diesel and biodiesel B15 fuel (15% sunflower oil mixed with 85% diesel, by volume) operating at different fuel injection timings. The results were acquired at engine speed 3000 rpm under full load conditions. A comparison between the numerical results and experimental data regarding the in-cylinder pressure was done in order to check the usefulness of this model. The results have shown that the engine performance of biodiesel B15 was slightly lower than that of pure diesel fuel. Concerning gas emissions; lower soot emission, higher NOx emissions of biodiesel B15 were obtained compared to those of diesel fuel at same operating conditions.
Influence of Powder Mixed EDM on the Surface Hardness of Die steel
Authors: Hameed Azzam Sabah , Hamdoon Farouk O. , Jafar Mohaned S. 
Published: June 2019

AbstractImproving the surface hardness of molds after EDM is still being challenged by many researchers. In this research, an effort was made to enhance the surface hardness of die steel though adding metal powder to dielectric and optimization parameters of EDM. process factors are workpiece types, concentrations, powder types, and electrical variables of the machine. Taguchi’s method has been used to design experiment and the results have been analyzed by ANOVA. The influence of the factors on micro hardness was evaluated though the mean and signal to noise ratio(S/N) of micro hardness. The results showed that, the mixing of Mn powder with insulator fluid results in high micro-hardness compared with aluminum powder, mixed powder of aluminum and manganese, also with pure dielectric. The significant factors for micro-hardness is a powder type (Mn) and has more contribution 43%. The factors of pulse on time and concentration have no significant effect on hardness of mold surface.
Mechanical Properties of Tin-Based Babbitt Alloy using the Direct Extrusion technique
Authors: Zainulabdeen A A , Hashim F A , Assi S H 
Published: June 2019

Abstract
Tin Babbitt is an ideal journal bearing material, because of its microstructural properties, which qualifies these alloys as a bearing material. Effect of the Babbitt die casting (ASTM B23 Alloy 2) on its microstructure and the hardness properties were studied. The forward extrusion type was carried out using cosine profile and the five different reduction area such 5%, 10%, 15%, 20% and 40%. The results show that the refinement of hard phases of Cu6Sn5 and SbSn led to increasing the hardness value after casting, and after extrusion for all reduction percent, except reduction 40%, the dynamic recrystallization is dominant which led to hardness decrease. The result also shows that the extrusion pressure increases with increasing the reduction value. Moreover, cold deformation improved the hardness properties for Babbitt alloy by refinement of the Cu6Sn5 phase.
Numerical investigation of stress analysis of composite materials with various elasicity
Authors: Egab Karim , Bahrian Yaesin , Okab Abdullah , Khalil Yasir , Oudah Saad K. , Akanda Abdus 
Published: June 2019

Abstract
Composite materials have a widespread use in engineering applications and modern structures because of the qualified physical and mechanical properties. Therefore, study the structures of composite material becomes attractive and reserchers to obtain novel materials that qualified environment updates. In this study, the displacements and stress analysis of two-dimensional composite materials have different modulus of elasticity and mechanical properties have discussed. Finite difference method was used in this study where the model solved using Fortran 90. The results show that, the change in elasticity in one of the layers has significant effects on the displacements and stresses distributions of the layers of the composite. In addition, the influence of passion’s ratio with elasticity at the same time is discussed. They have important effect on the stress analysis. The results were in the acceptable limit which confirms the reliability of the finite difference method.
Effect of die geometry on thermal fatigue of tool steel in aluminium alloy die-casting
Authors: Ghusoon R M , Rawaa H M , Basim H A 
Published: June 2019

Abstract
In this paper, die geometry and its effect on the thermal wear of H13 steel was evaluated during aluminium die-casting. During the investigations, an innovative dipping testing device was used. The process involved a cyclic aluminium alloy-melting die and water-cooling process, which allows a dominated cycle of thermal fatigue. The H13 tool steel was first prepared with different end geometries before been subjected to the cyclic heating and cooling (in a water basin) processes. During the heating and cooling processes, the produced hardness profile, surface cracks, and the microstructure of the samples were regularly analysed after a predetermined number of cycles. The effect of the sample end geometry, sample thickness, material of the sample, and the dipping test parameters on the thermal stress was also investigated. From the metallographic investigation of the sample surface, the thermal fatigue resistance of the sample was observed to be enhanced due to the improved die steel protection from oxidation. Oxides can permeate cracks at the corrosion pits and cause the propagation of cracks through the production of a tensile stress from the increased oxide volume at the crack tip. The improved thermal fatigue resistance of the tool steel was contributed by the ductility and high yield strength of the tool steel.
Development product of a multi-layer solar distillation system connected to tubular solar collectors by using gravel
Authors: Abed Muntadher H. , Kassim Muna S , Saleh Fouad A. 
Published: June 2019

Abstract
Solar distillation occurs within a device called the (solar still). There are many types of solar still. In this study, the addition of modern technology for solar still was used. Experimental tests have conducted in (Baghdad), the capital of (Iraq). On the other hand, (MAT LAB) program was used to formulate mathematical formulas. The study was conducted during (July) and (August) and extended during the testing day from (5:30 am) to (10:00 pm). Coarse and fine gravel added to the solar still basins to develop its product. The percentage of increase in the production of solar still with the presence of gravel was (47%), the percentage increase in night productivity was (64%).
Numerical and experimental investigation of parameters affect the forming load during rubber pad sheet metal forming
Authors: Younis Karem M. , Aljarjary Adnan I. , Shukur Jalil J. 
Published: June 2019

Abstract
The flexible die forming of sheet metal with the aid of rubber pad as a pressure-carrying medium is one of the advanced forming technologies for sheet metal forming components. In this research, rubber pad forming process was used to produce cups with different shapes. The sheet made from low carbon steel with a thickness of 0.5 mm. The rubber pad has made from polyurethane with different values of hardness and thickness which are (50, 60 and 70) shore A, and (40 and 80 mm), respectively. This pad is used to apply counter pressure to form the sheets. The former block is with three different shapes, which are flat, hemispherical, and complex. A numerical study has conducted to look into the deformation style of this process by 2D-FE simulation under the ANSYS Workbench platform. Numerical and experimental results illustrate that the forming load increases with increase rubber hardness while it decreases with increase the rubber pad thickness.
Selecting the Most Efficient Bearing of Wind Turbine Gearbox Using (Analytical Hierarchy Process) Method “AHP”
Authors: Mankhi Tahseen Ali , Legutko Stanisław , Al-Bedhany Jasim H , Muhsen Abdulmuttalib A. 
Published: June 2019

Abstract
It has been clearly observed that wind turbine energy gearbox bearings are being subjected to premature and unpredicted failure during the first one-fourth duration of their lifespan. This failure is related to many effective factors that have multiple criteria for many available alternative bearings. This article deals with Analytic Hierarchy Process (AHP) and uses a software tool, so called (Expert Choice EC) to select the best compromise solution of the most efficient bearings in wind turbine gearbox. Three types of bearings have been entered in EC comparison: (single-row tapered, single-row cylindrical and double-row cylindrical) roller bearings under five main elements of criteria: (cost, durability, reliability, feature design and availability). Based on the synthesis results and sensitivity analysis of EC software, it can be concluded that single-row tapered bearing is the best choice to be used in wind turbine gearbox of about 52.1% than the other two alternatives taking in considering that the main two criteria, which cause premature failure, are durability and reliability.
Numerical verification for different types of curved baffles as stratifiers in solar thermal storage tank
Authors: Abbas Hashim Ali A. , Abdulrasool Adnan A. 
Published: June 2019

Abstract
This paper aims to assist the thermal stratification in hot water storage during the partial discharge water. Three different types of curved baffle have been studied each one placed in the bottom of a rectangular standard conventional tank in order to reduce the turbulence mixing of inlet jet. The purpose of this investigation is to numerically study the impact of the curved baffle within a vertical hot storage tank and compare three different baffle designs to select the best one. A three-dimensional computational fluid dynamic (CFD) model was performed using the commercial software package CFX 18. The numerically simulated tank result was validated against the experiment data. The numerical transient temperature distribution and the flow characteristics were analyzed, and then a comparison was made between the three baffle designs and the calculated performance parameter. The results manifested that the curved baffle has a significant effect for enhancing the thermal stratification at high flow rates. Design C showed the best thermal stratification due to the downward curvature shapes.
Fabrication of Porous NiTi Shape Memory Alloy Objects by Powder Metallurgy for Biomedical Applications
Authors: Dawood Nawal Mohammed , Abid Ali Abdul-Raheem Kadhum , Atiyah Alaa Abdulhasan 
Published: June 2019

Abstract
This research, studied the effects of compacting pressure (150-450) MPa and Copper additions (2.5, 5, 7.5 and10) wt% on the mechanical properties of NiTi based shape memory alloys prepared by powder metallurgy. Several mechanical tests such as Rockwall macro hardness measurements, compression test and shape memory properties of the prepared alloys were achieved. The results showed that the addition of Copper with (2.5-10) wt. % to NiTi prepared alloy resulted decreasing the hardness relatively with comparison to master alloy without copper also, there is a distinguished increase in SME properties obtained from hardness test for the NiTi alloys with addition of copper. The result showed that the increasing in compacting pressure and Cu additives have an essential effect by improvement the mechanical properties of the prepared alloys.
Synthesis and Characterization of Nanocoatings Thin films by Atomic Layer Deposition for Medical Applications
Authors: Wadullah Haitham M. , Ajeel Sami Abualnoun , Abbass Muna Khethier 
Published: June 2019

Abstract
In this work, synthesis and characterization of Al2O3, TiO2and Al2O3 / TiO2hyper thin films, with 25 nm and 50 nm,have been investigated by using Atomic layer deposition method (ALD) at high vacuum (0.27 Torr) onto the cobalt chromium alloy (ASTM F75) and si-wafer (100) substrates. The characterizationshave been investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), optical profilometer and ellipsometry spectroscopy. Morphological characterization and thickness evaluation has been obtained by optical profiler and ellipsometry spectroscopy respectively. SEM has been used to find the presence of thin film defects and the particle shape/size of the thin films. EDX has been used to obtain the element analysis of the thin films. The results have shown good quality thin films, homogeneity, without defects or micro-crack and good thin films properties. Small crystalline regions have been found in the TiO2thin film by selected area diffraction pattern(SADP) image. Al2O3ALD film exhibited lower surface roughness values and good thin film thickness control compared with TiO2and Al2O3 / TiO2.
Effect of Static Spark Timing on the Performance and Emissions of a Spark Ignition Engine Using CNG
Authors: El-Sharkawy Mohamed R. , Abaskharon Mina B. R. , Abd-El-Tawwab Ali M. , Ezzat Fawzy M. H. 
Published: June 2019

Abstract
In this paper, studying the effects of static spark time on the performance and emissions of a spark ignition engine using compressed natural gas. Engine performance and emissions were measured repeatedly at different static ignition time (15° BTDC, 18° BTDC, 21° BTDC and 24° BTDC) with fixed coolant temperature (90°C± 2°C). the results showed that advancing the static ignition time with CNG from 15° BTDC to 24° BTDC at the full load increased the brake power, brake torque, brake thermal efficiency and hydrocarbon by 4.07%, 4.67%, 3.58% and 4.89% respectively, while carbon monoxide and volumetric efficiency doesn’t change effectively at the full and half load conditions.
The Radius Size Variation Effects on Fatigue Strength of AA6061-T6 and AA6061-O Alloys
Authors: Saleh Ali Hassan , Nasser Ali Mohammed Ali , Ismail Muammar Ibrahim , Abood Adnan Namaa 
Published: June 2019

Abstract
This research ensured the effects of radius variation on fatigue – life of AA6061-T6 and annealed alloy, AA6061-O. Five different sizes of radius (1, 2, 4, 8, and 16) mm were studied using Neuber notch factor (Kf) instead of the theoretical stress concentration factor (Kt). The numerical modeling was adopted using ANSYS Workbench 15 to evaluate the radius size effectiveness on strain and stress distribution, while the experimental procedure carried out to determine the strain-life constants for analytical calculations. The results show that the reduction in the radius leads to increase stress, while the strain remains close to each other with the variations of radius for both alloys. The decrement in stress and strain values for annealed specimens were observed in comparison with base alloy. The transition life (NT) was decreased whenever the radius decreased in both alloys. The fatigue life of annealed specimens increased for all values of radius compared to the specimens without annealed. The comparison of the fatigue life between the experimental and numerical results shows that the experimental results have more than those obtained by numerical estimation and this indicated the validity of the numerical approach.
A New Techniques to Calculate the Efficiency of Electric High Voltage Network in Basra
Authors: Aish Qais Mohammed , Abed Wathiq Rafa 
Published: June 2019

Abstract
The complexity of electrical power system that need to provide electricity to many customers under different requirement with high efficiency. For this reason, its imperative to find a modern technology that can be implemented to obtain reliable electrical power network. In this paper is a new technique have been proposed based on the load flow direction from generation station to substations. Keep track of route method was implemented to determines the path of the load flow and give minimum disconnected. Matlab environment software was implemented later to discover the weaknesses point and calculate the efficiency of the electric power network.
Design System of Optical Heterodyne Detection Based on Temperature Sensor
Authors: Resen D A , Kadhim S A , Mahmood A I , Lateef A T 
Published: June 2019

Abstract
Optical Heterodyne Detection (OHD) technique is based on two separate sources with optical interference between them. The optical signal from a specific light source is compared with a separate reference signal from another source. The Fiber Bragg grating (FBG) reflect a specific wavelength λ
B
and transmit the other wavelengths within the laser source spectral. This is achieved by changing the refractive index generated by periodic variation of optical fiber core, which reflect a specific wavelength, so FBG can be used to withhold a certain wavelength and allow other wavelengths to transmit. In this paper, a new method of an OHD has been designed using Optisystem software. Optical fiber as a temperature sensor element with single source and two FBGs have used in this system. the first FBG used as a tunable source and the other has used as a sensing element. The two optical signals have been combined utilizing a photodetector. It has a linear response to the light energy, while having a quadratic response with the amplitude of the electromagnetic field. The results show that the beat frequency shift has a linear response to the temperature with sensitivity about 2.24 GHz/Co.
The effects of sand and pipes on the temperature distributions of the underground cable
Authors: Al-Baldawi Ibtisam A. , Alsakini Sahar R. , Abed Mohammed S. 
Published: June 2019

Abstract
With the proliferation of underground systems and technologies, the investigation of thermal fields in the soil has become a subject of great attention in the emerging technology of buried structures. In this work, the heat transfer mechanisms in underground cable installations have presented. This paper considers a system of the underground cable of 12/20 (24) kV single core cable with a copper conductor and XLPE insulation, located in three models were designated for the experiment, a cable was located in (sand, PVC pipe, and an aluminum pipe). Furthermore, its reviews the results were obtained from a laboratory model where a wooden box was used, and the cable was placed inside the box by burying the cable in three different designs and using the soil used in Iraq and obtained a good results and comparisons were made at each model.