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Aims and Scope
Editorial Board

1. A novel vortex-assisted generation system for hydrokinetic energy harvesting from slow water currents

Ulugbek Azimov, Jack Callaghan, Iman Frozanpoor, Callum Hulsmeier, Christopher Kwok, Matthew Nixon

Mechanical and Construction Engineering Department, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom.

Abstract: A novel system has been developed that harnesses the phenomena of vortex-induced vibrations (VIV) from a slow current (<0.5 m/s) of water to generate renewable hydrokinetic energy. It utilizes a single degree-of-freedom pivoting cylinder mechanism coupled with an electromagnetic induction generator. As a result of observation and concept development, the final prototype includes a stationary cylindrical shedder upstream of the oscillator. The system is referred to as ‘Vortex Assisted Generation’ (V.A.G.) throughout the report. Given the novelty of the system, an extensive investigation has been conducted to identify key parameters and functional relationships between system variables, regarding their effect on output voltage, frequency, and power. A range of flow velocities have been established that instigate system lock-in, where the cylinder oscillates at high amplitude and frequency. For the tested prototype up to 37% of system extraction efficiency has been achieved in the lab conditions.

Volume 9, issue 4, 2018, pp.317-352.

2. FPGA based intelligent FDI system for proton exchange membrane fuel cell PEMFC

Hussein M. H. Al-Rikabi¹, Abbas H. Issa²

1 Imam Al-Kadhum University College, Najaf, Iraq.

2 Department of Electrical Engineering, University of Technology, Baghdad, Iraq.

Abstract: A Fault Detection and Isolation (FDI) system for proton exchange membrane fuel cell (PEMFC) has been presented in this paper. Artificial Neural Network (ANN) is used to detect the faults. An Input\output data set have been acquisitioned from PEMFC and used to design an ANN model. The model designed gives a steady state prediction for a given input. The output of the PEMFC is compared to the output of the model, then a residual signal is monitored and used to detect the faults. Three types of faults have been studied in the presented work, which are: Abrupt, Incipient and Intermittent faults. The steady state model designed and simulated using Matlab. Then the ANN model has been downloaded to a hardware platform which is Spartan3 starter FPGA kit. The challenge of this study is to convert the FDI system to VHDL code to be downloaded to the FPGA. Due to the hardware limitation, the performance decreased by 5% and using an advanced features FPGA kit could remove that limitation.

3. Influence of additives to biodiesel-diesel blend on a modern tier-4 turbo-charged diesel engine’s idling emissions

Mohamed Errishi, Murari Mohon Roy, Osama Ahmed Elsanusi

Department of Mechanical Engineering, Lakehead University, Thunder Bay, Ontario, Canada P7B 5E1.

Abstract: This study focuses on investigating the effects of several additives on diesel engine’s idling emissions. Experiments using a modern (Tier-4) 4-cylinder direct injection (DI) diesel engine were investigated at two idling speeds. The fuels investigated were B0, B40 and B100. Four additives, namely methanol, ethanol, diethyl ether (DEE) and water were mixed with B40 blend. The engine tested from cold start to warm-up conditions, and the average results were analyzed. The engine’s fuel consumption, exhaust gases temperature (EGT), and regulated emissions were investigated. The regulated emissions investigated were oxides of nitrogen (NOx), carbon monoxide (CO), unburned hydrocarbon (HC) and smoke opacity. All additives improved NOx and smoke emissions compared to its base fuel.

4. Urbanization and sediment control using intelligent system

Ibrahiem Abdul Razak Al-Ani

Department of Civil Engineering, Al-Farabi University College, Baghdad, Iraq.

Abstract: Soil erosion is one of the most important natural resources management problems in the world and the source of sediment that pollutes streams, fills reservoirs, and causes dramatic impact to the aquatic eco-system. Urbanisation is one of the significant agents of sediment generation due to soil disturbance and rainfall events. To capture the sediment generated from the construction before impacting the surrounding environment, a well-designed sediment basin is required. The use of knowledge-based systems has been significantly recognized as a way to combine scientific understanding of the process of the natural world with the heuristic rules developed by managers through observation and experience. In this paper, a rule-based decision support system has been developed for designing the dry and wet sediment basins for Malaysian construction sites using Visual Basic Tool. The design which is based on local studies and guidelines includes sizing the basin, sizing of emergency spillway, calculating the sediment basin trapping efficiency and maintenance frequency for both of the dry and wet basin. Preliminary validation, field validation and Turing test were applied for validating the developed system in which the results from this study showed that both of the system and the expert's opinions are almost matching which denotes that the system is intelligent and behaves like a human expert. The system can be considered as a "green technology" tool since it minimizes environmental impact.

5. Analytical and experimental investigations for the pressure distribution between the stump and the Syme’s prosthesis

M. J. Jweeg¹, A. A. Alhumdany², H.A. Hamzah²

1 Department of Scientific Affairs, Telafer University, Iraq.

2 Mechanical Engineering Department, College of Engineering, Kerbala University, Iraq.

Abstract: This study aims to suggest an analytical indirect approach to find the pressure distribution at the stump-socket interface in the Syme's prosthesis. The results are compared with those obtained experimentally using the F-socket device. Finally, a finite element model was built to analyze the effect of the internal pressure on the socket. The analysis was made in the SOLIDWORKS subprogram in both static and dynamic solutions. The results show that there is a great agreement between the experimental and analytical results so it is possible to dispense the results of the F-Socket device in cases of the unavailability of it and depend on the analytical solution.

6. Effect of lubricant temperature on the dynamic and stability behavior of journal bearing

Basim A. Abass, Zainab S. Hamzah

University of Babylon, College of Engineering, Department of Mechanical Engineering, Iraq.

Abstract: The effect of temperature on the dynamic behavior of journal bearing has been investigated in the present work. Time dependent Reynold's equation modified to include the effect of oil film temperature has been perturbed in order to calculate the eight dynamic coefficients required to evaluate the dynamic characteristcs of the journal bearing. The oil film temperature was obtained by solving numerically the energy and heat conduction equation simultaneously with the Reynolds equation using appropriate boundary conditions. Suitable oil viscosity temperature has been used which couples the Reynolds and the energy equations. The effects of bearing aspect ratios and journal speed on the dynamic and stability characteristics of the rotor bearing system have been studied. Ranges of bearing aspect ratio from 0.5 to 1.5, speeds from 2000 to 8000 rpm have been considered. The mathematical model as well as the computer program prepared to solve the governing equations has been validated by comparing the results for the dynamic coefficients (stiffness and damping) obtained in the present work with that obtained experimental results from the literatures. The results seem to be in a good agreement with percentage of error less than 3%. Comparing to the isothermal analysis, a destabilizing effect has been noticed when the oil film temperature was considered. The results show that the critical mass decreases by 33% when the bearing works at an eccentricity ratio of 0.4.

7. Direct slicing techniques of 3D surface model in layers manufacturing

Ali W. Aldeen Baqer¹, Tahseen F. Abbas²

1 Department of Materials Engineering, Kufa University, Iraq.

2 Department of Production and Metallurgy Engineering, University of Technology, Iraq.

Abstract: Layered Manufacturing (LM) which is the core of Rapid Prototyping (RP) the part is generating using layer-by-layer addition of the material. Where slicing of the Computer-Aided Design (CAD) models on a part to be produced is one of the important steps. Direct slicing a three-dimensional (3D) graphic model into layers of two-dimensional (2D) contour plots is an essential step for all rapid prototyping (RP) machines. This paper establishes a base surface parameterization using direct slicing strategy for based on a vertical sectional design technique using different layers thickness at 3D surface and study the effect of slice thickness on the final 3D model accuracy. The proposed method directly extracting 3D to vertical sectional contours from mathematical definition of parametric surface and converting to (2D) layers, the final surface achieved by manufacturing layers using Computer Numerical Control (CNC) laser cutting machine. A measuring method has been proposed and implemented to measure the accuracy of the final 3D surface. statistical method of error assessment and similarity factor have been implemented in this work to show the efficiency of the proposed work and comparing between original CAD models and prototyping models. The results of similarity factor show that, (84.317%) for 2.5 mm Bezier model, (72.492%) for 4mm Bezier model, (61.012%) for 8mm Bezier model.

8. Investigation of dynamic properties of sandwich beam using oberst beam method

Hatem Hadi Obeid, Huda Nadhim Mohammed

University of Babylon, College of Engineering, Department of Mechanical Engineering Iraq.

Abstract: The Oberst beam method is widely using to measure the mechanical and dynamic properties of materials, such as the Young's modulus, it has been supplying required data for numerical analysis of structures and this method was been used with a composite materials, that has been consist of two skin layers (steel, aluminum) between them the core layer. This paper provides a brief description of the Oberst beam method by applied modal analysis and ASTM E756-05, the impact hammer is used to generate excitation for the beam and obtain a studied response. The boundary condition (Fixed-Free) was applied, it uses three different lengths beams. It was applied this technique in this current work for the two parts. The first part include a composite beam that consists of two skins (Galvanized steel) between them a layer of Polyurethane (PU) Rigid foam core. The second part skin was separated from the core of a composite material beam in (470) mm length beam. It has been obtaining the Young's Modulus for both core and skins over a frequency range of (30-1000) Hz. And compared results between (Experimental and Theoretical) by using finite element method (FEM). Found in low frequencies, the value of the Young's Modulus almost constant, but in high frequencies the value of the Young's Modulus were decreasing with increasing frequency. While found the value Young's Modulus remain almost constant, When the skin layer is separated from the core.