Cover

Aims and Scope
Editorial Board

1. Experimental and numerical analysis of cross-ply and angle-ply composite laminated plateshaving various shapes of cut outs

Muhsin J. Jweeg¹, Muhannad Al-Waily²

¹Telafer University, Ministry of Higher Education & Scientific Research, Iraq.

²Mechanical Engineering Department,Faculty of Engineering, University of Kufa, Ministry of Higher Education & Scientific Research, Iraq.

Abstract: In this study, the experimental and numerical work is presented to study the effect of cutout size, shape, and number on the deflection and stresses in x and y-directions for simply and clamped supported boundary condition of cross and angle-ply laminated plates. The experimental work involved the effect of the cut out size, shape, and number on the deflection and stresses. A comparison study for the deflection and stress results have been achieved between the experimental and those obtained numerically using the finite element method employing ANSYS program Ver. 14. Various support conditions for the plates were adopted with different number of layers and fiber orientations. The shapes of cut out are square, circular, and fillet for different aspect ratios AR=1 and 2. The results showed that the amplitude values of square one are less than that for other types in cross-ply laminated plates and more than that for other cutouts in angle-ply laminated plates for aspect ratio a/b=1. Also the amplitude values of plates with square hole are more than that for circular hole for laminated plates with aspect ratio a/b=2. The stresses increase with increasing of the cutout size, and the increasing of fillet radius decreases the stresses. The comparison study shows a maximum discrepancy of deflection about (9.54%) and maximum discrepancy of stress results about (12.45%).

Volume 7, Issue 6, 2016, pp.443-456.

2. Modular socket system versus vacuum technique in trans-tibial prosthetic socket

Ikram R. Abd Al-razaq, KadhimKamilResan, Yasir Khalil Ibrahim

College of Engineering, Al-Mustansiriyah University, Baghdad, Iraq.

Abstract: Below knee socket manufactured by fast process (working time does not exceed two hours) called Modular Socket System (MSS) that applied direct laminated of 4 carbon layers, The mechanical properties were compared with the available process in Iraq ( working time exceed weeks) this is called Vacuum that applied 8 layers of perlon. Materials were subjected to tensile, creep (50°C).Creep test data were analyzed to obtain creep compliance by standard linear solid. Failure characteristics at room temperature, at (50°C) were determined by fatigue testing. Interface pressure was calculated using F-Socket, ANSYS was used to determine safety factor and total deformation. MSS process has high strength at rate 510% and young modulus at rate 263%, and creep compliance reducing at rate87%. MSS has highest fatigue limit, the safety factor of groups A and B decreased at rate (5.6%, 58.5%) respectively with the temperature effect and the total deformation decreased at rate 72%.

3. Free vibration investigation of isotropic composite skew plate with different shapes holes

Mohsin A. Alshammari, Ban HussienKassab

Mechanical Engineering Department-Engineering College –Bagdad University-Iraq.

Abstract: The experimental and numerical investigations of free vibration study of composite skew plate are done. The free vibration characteristics are determined numerically using ANSYS package. A comparison between these investigations is done also. The effects of the skew angle, thickness of plate, central hole shape, and a percentage of hole area to the plate area on the free vibrations characteristics of isotropic skew plates were discussed. The rapprochements between results show good agreements between the experimental and numerical results. The natural frequencies generally are increased with an increasing in the skew angle; also the natural frequencies are increased with the increasing of the plate thickness, and are decreased with the increasing of the area of the hole. Three shapes of holes had been studied (circular, square and triangular) holes, the natural frequency reaches the maximum value for the circular hole, and the minimum value for the triangular hole.

4. Graphical user interface (GUI) for design of passenger car suspension system using random road profile

Duna Tariq Yaseen

Machine and Equipments Department, Basrah Technical Institute, South Technical University, Iraq.

Abstract: In this paper, an Interactive approach has been introduced for the design of Passenger car suspension system subjected to random road profile, by building a graphical user interface (GUI), using Matlab/Guide has been presented. The aim of the work is to show the importance and usefulness of the developed GUI in designing and describing the dynamic behavior of car suspension system for different design criteria. Common problems in the field of design of suspension systems for the quarter-car passive model are analyzed. The result shows that the designed GUI is very convenient for engineers, analysts, and designers of car suspension systems.

5. The effect of titanium dioxidenanoparticles thin layer on overall performance of dye sensitized solar cells

Mohammed Ali Abdulrehman, Ahmed K. Al-kamal, Ali Abed Salman

Materials Eng. Department, College of Engineering,Almustansiriya University, Iraq.

Abstract: This research studied the effect of TiO₂ thickness layer on Dye sensitized Solar cell DSSCs. Photo-anode was fabricated by depositing a TiO₂ paste on fluorine–doped SnO₂ (FTO) substrate glass and sintered at 500 °C for 2 hrs. Different thickness (3.6, 9, and 12) µm of TiO2 layer has deposited on FTO glass. The thickness of the layer was measured using scanning electron microscope SEM .The results show that the thickness of 9 µm gives the best performance in term of short-circuit current Iscas compared to other thickness layers due to the generation of photo electron.

6. Testing and modeling of damages in composite laminates subject to low velocity impact

Al-Hadrayi Ziadoon M. R, Zhang Yunlai, Zhou Chuwei

State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, 29Yudao Street 210016, Nanjing, China.

Abstract: In recent years, composite materials were used extensively in the most important industries, especially in aerospace industries and aircraft structures due to its high strength, high stiffness, resistance of corrosion, and lightweight. The problem is how to choose the perfect design for composite laminates. And study the effects of modeling of the stacking sequences of composite laminates on failure modes (delamination, matrix cracking, and fiber failure) under the test of low velocity impact. This paper has validating to the experimental results that has published. The composite used was carbon fiber /epoxy (CFRE), (UD ASTM/D6641) as three groups [A, B, C]. It had same material system. The difference was only in stacking sequences as random design. These models were simulated numerically by the commercial software implemented into the FEM/ABAQUS 6.9.1 with subroutine file (VUMAT) a user-define 3D damage model. The results had good agreement with experimental results.

7. Sisal natural fiber reinforcement influenced with experimental and numerical investigation onto vibration and mechanical properties of composite plate

Zaman Abud Almalik Abud Ali

Mechanical Engineering Department, Faculty of Engineering, Al-Kufa University, Iraq.

Abstract: This study interested in preparation of composite material specimen by using natural fibers sisal and polyester resin. The specimens were pretreated in different of volume fraction of sisal and resins which are were (05-35) % sisal, respectively. Specimen model fabricated had plate shape, where, can be applying vibration test and tensile test. Specimens were tested by using tensile properties test. Results reveal that the best specimen had mechanical properties was (A) which are (35-65) % sisal-resin, where, specimen appeared best modulus elasticity in longitudinal fibers E1 (5.925) Gpa so lower value modulus elasticity in transverse fibers E2 (4.860) Gpa for same specimen. (A) specimen gives stronger material compared with at each of specimens, which indicates high toughness and strength of materials because reinforcement of sisal fibers use of a higher percentage of fiber 35%. Specimen were tested vibration test as types of fixations of specimen, result reveal  the natural frequency high at clamped supported four edges (CCCC), (202.73)Hz compared at each of another specimens, because (CCCC) specimen had high volume fraction of plant fiber sisal and less volume fraction of polyester resin (35-65) % sisal-polyester. Natural frequency was obtained by using numerical analyzing at running ANSYS program (VER.14). the results finding, there are similarity between behavior of composite material samples from where, natural frequency and volume fraction , results reveal that numerical analyzing of plate composite materials was little better from experimental work but both of tests in simulation and experimental test appear same of final results which (CCCC) specimen was better at of each specimens to apply strength of materials and whenever increasing volume fraction of sisal obtained high strength of material.

8. Effect of PMMA particles on rigid polyurethane foam composites

Ismail Ibrahim Marhoon

Al-Mustansiriayah University, Collage of Engineering, Materials Engineering Department, Iraq.

Abstract: Rigid polyurethane foam composite was prepared for thermal insulation applications, such as interior foam spraying in building structures by adding addingpolymethylmethacrylate (PMMA) particles and by studying the effect of selected particles sizes of 45, 63, and 75 μm with 5, 10, and 15% wt. content of PMMA particles in some mechanical and physical properties of the produced foam composites. Results show that the flexural strength, flexural modulus, impact strength, and density rise with an increase in weight fraction and decrease in particle size. The hardness increases with an increase in weight fraction and decrease in particle size. The thermal conductivity is enhanced when the added PMMA particles decrease with an increase in the particle weight fraction content and decrease in particle size. SEM confirms the presence of some mechanical enhancement in the resultant foam composite.

9. Multi fault detection of the roller bearing using the wavelet transformand principal component analysis

Jaafar Khalaf Ali, Qusai Talib Abdulwahab, Sajjad Nayyef Abdulkareem

Mechanical Engineering Department, College of Engineering, Basrah University, Ministry of Higher Education & Scientific Research, Basrah, Iraq.

Abstract: Vibration monitoring and analysis techniques are the key features of successful predictive and proactive maintenance programs. In this work, advanced vibration analysis techniques like Wavelet transform, Principle Component Analysis (PCA) and Squared Prediction Error (SPE) have been used to detect the faults in bearing. Discrete Wavelet Transforms (DWT) decomposes signal to high and low frequencies. PCA is employed to extract important feature and reduce dimension. SPE is used to detect the bearing faults. The experimental data is collected from SpectraQuest's Machine Fault Simulator (MFS-4) apparatus. In this study, four rollers were bearing defects (ball defect, outer race defect, inner race defect and combined defect) for 1" and 3/4" bearing. From the results, the suggestion techniques can be used to detect multi-faults in the bearings. The results show that the best wavelet function is Coiflets4 in this method.