Current issue of "International Review of Mechanical Engineering (IREME)"

by Syed Ashfaq, S. A. Khan, E. Rathakrishnan

Abstract - This paper presents the results of experimental studies to control the base pressure from a convergent nozzle to ascertain the effect of level of expansion on a suddenly expanded sonic flow. An active control in the form of four micro jets of 1 mm orifice diameter located at 900 intervals along a pitch circle diameter of 1.3 times the nozzle exit diameter in the base region was employed to control the base pressure. The area ratio (ratio of area of suddenly expanded duct to nozzle exit area) studied is 2.4. Experiments were conducted for nozzle pressure ratio (NPR) from 1.5 to 3, in steps of 0.5. The length-to-diameter (L/D) ratio of the enlarged duct was varied from 10 to 1, and tests were conducted for L/D 10, 8, 6, 5, 4, 3, 2 and 1. It is evident from the results that the flow field downstream of the reattachment-redevelopment is very complex. It is found that, unlike in the case passive controls, the favourable pressure gradient does not ensure augmentation of the control effectiveness for active control in the form of micro jets. To study the influence of micro jets on the quality of flow in the enlarged duct wall pressure was measured and it is found that the micro jets do not disturb the flow field in the duct.

Keywords: Base Pressure, Mach Number, Micro Jets, Sudden Expansion, Wall Pressure.

by Hanim Mohd Yatim, Intan Z. Mat Darus

Abstract - This paper presents an investigation into the development of an intelligence parametric identification for a single-link flexible manipulator system using genetic algorithm (GA) and particle swarm optimization (PSO). The global search technique of GA and PSO employ different strategies in the area of algorithm design, natural basis and computational effort in order to find the solution of a given objective function. A simulation environment characterizing the dynamic behavior of flexible manipulator system was first developed using finite difference (FD) method. The flexible manipulator was driven by a bang-bang torque and the input-output data of the system acquired is used for system identification using GA and PSO techniques based on autoregressive model structure. The identification is performed on basis of minimizing the mean-squared error (MSE) between the measured and estimated outputs of the flexible manipulator. The validation of the algorithm is assessed with correlation tests and in time and frequency domains. It is demonstrated that the PSO has perform far better with the value of MSE is 3.0147 � 10^-6 compared to GA with 1.4908� 10^-4. The best model obtained characterizes the dynamic behavior of the system well and will be used in the future for control design and development.

Keywords: Dynamic Modeling, Finite Difference Method, System Identification, Single-Link Flexible Manipulator, Particle Swarm Optimization, Genetic Algorithm.

by S. A. Adam, M. A. Fairuz, M. S. Hussain, M. R. M. Hafiezal, S. N. Khaironisa

Abstract - The study was focused on the effect of using Sunflower Oil as a lubricant during turning operation of Stainless Steel. Cutting speed, feed rate and depth of cut were set as the control factor for the machining operation. An Orthogonal Array of L4 (2�) was used. Then ANOVA analyses were carried out to identify the significant factors affecting surface roughness, Ra and tool wear, Vb, and determined the optimal cutting combination design by seeking the responses and signal-to-noise ratio. Finally, the confirmations run can optimize the optimal parameters and cutting fluid for surface roughness and tool wear.

Keywords: Sunflower Oil, Taguchi Method of Orthogonal Array, ANOVA, Surface Roughness, Tool Wear.

by Ehsan Rasooliyazdi, Rizal Bin Zahari, Ali Ghadianlou, Ali Farhaninejad, Barkawi Bin Sahari, Faieza Abdul Aziz, Hamed Jamali

Abstract - Side Door Beam (SDB) is one of the crucial parts of today�s vehicles in order to meet the passenger safety. Through an explicit finite element analysis (FEA), material selection for the SDB under impact is evaluated by using three different sheets of material to achieve the maximum possible specific energy absorption (SEA). To find the lowest peak load, the carefully chosen SDB is investigated based on its orientation angle toward the rigid wall impactor. The elliptical cross section of the selected SDB is taken into account by considering two variables of geometrical parameters; thickness and minor to major diameter ratios. Accordingly, Multi-objective optimization of the SDB is performed using response surface method (RSM) to reach the mentioned objectives and to determine the optimal sectional configuration of the SDB.

Keywords: Crashworthiness, FEA, Elliptical Beam, Multi-Objective Optimization.

by N. Godwin Raja Ebenezer, R. Saravanan, S. Ramabalan, R. Natarajan

Abstract - Optimal structure design for robots is fundamentally important, as it stands first in the order of robotic system design. The structure of industrial robots should be robust, versatile and strong enough � to withstand a variety of forces/loads, guarantee stability and security in operation. To achieve best solution, it is desirable to perform structure design optimization. Here, it is proposed to determine optimal geometric dimensions for a task specified 6-link planar robot considering pick and place operation. The aim is to minimize torque required for defined motion and to maximize manipulability measure of the robot subject to dynamic, kinematic, deflection and structural constraints. Links physical characteristics (length and cross sectional area parameters) are design variables. Five different cross-sections (hollow circle, hollow square, hollow rectangle, C-channel and I-channel) have been experimented for the link. Evolutionary algorithms viz. Elitist Nondominated Sorting Genetic Algorithm (NSGA-II) and Multi Objective Differential Evolution (MODE), Multiobjective Genetic Algorithm (MOGA) are used. Normalized weighting objective functions and average fuzzy membership functions are used to select the best optimal solution. Multiobjective performance measures, namely, Solution Spread Measure (SSM) and Ratio of Non-dominated Individuals (RNI) are used to evaluate Pareto optimal fronts. Two other multiobjective performance measures, namely, Optimizer Overhead (OO) and Algorithm effort are used to find computational effort of optimization algorithms. Results obtained from various techniques are compared and analyzed.

Keywords: Optimal Structure Design, Task Specified Robots, Pick and Place Operation, Multi Criteria, Evolutionary Techniques � NSGA-II, MOGA and MODE, Dynamic, Kinematic, Structural Constraints.

by S. Hussain, , Y. Fukatani, M. Kohno, K. Sefiane, Y. Takata

Abstract - A 2-dimensional simulation of FC72 sessile droplet evaporation on a substrate layer consisting of silicon and Kapton tape has been carried out to study the heat and fluid flow inside the droplet as well as its surroundings. The momentum and volume fraction (VOF) equations were solved simultaneously with the heat and diffusion equations to obtain the flow profiles. The simulated conditions were based on actual experiments. This paper presents the findings for the simulated experimental condition for the same substrate and surrounding temperature under a constant contact line condition. The initial conditions for the substrate, surroundings and droplet was set to, as best as possible, the same condition as the experiment. Quantitative as well as qualitative comparisons were made between the experimental and simulated results. The simulation also predicted the temperature and concentration fields inside and outside the evaporating droplet. The predicted temperature and heat transfer profiles were compared to experimental results and were found to be qualitatively agreeable.

Keywords: Droplet Evaporation, CFD, Temperature, Concentration.

by Florian Ion T. Petrescu, Relly Victoria V. Petrescu

Abstract - This paper presents an algorithm for setting the dynamic parameters of the classic main mechanism of the internal combustion engines. It shows the distribution of the forces (on the main mechanism of the engine) to the internal combustion heat engines. With these strengths, and together with velocities of kinematic couplings is established then the heat engine efficiency. The method is applied separately for two distinct situations: when the engine is working on a compressor and into the motor system. For the two separate cases, two independent formulas are obtained for the engine yield. With these relationships are then calculated about mechanical efficiency of Otto heat engine, four stroke, two-stroke and 4-stroke V. Final yield of the engine is obtained considering and thermal efficiency given by Carnot cycle.

Keywords: Forces Distribution, Velocities, Powers, Yield, Internal Heat Engines, Compressor System, Motor System .

by J. Manikandan, V. Senthil, S. Nagarajan

Abstract - The main objective of this work is to improve the performance of multi stage mixed flow submersible pump. This pump highly depends upon the complex configuration of the Bowl-Impeller Interaction and the flow behavior of water in the same region. A commercial Computational Fluid Dynamics (CFD) code, namely ANSYS Fluent V13.0 with a k-ε Realizable turbulence model was used to study the effects of Bowl-Impeller Interaction. An extensive approach is tried to predict the flow behavior of the pump. The space between the bowl and impeller is called as �Axial gap�. In the existing model the axial gap between the bowl and impeller is 17mm. In this paper, the investigation of Bowl-Impeller axial gap for six different models is varied from 2mm, 5mm and 10mm (Increase and Decrease) to predict the performance of the pump. The numerical results are compared with the Best Efficiency Point (BEP) of experimental data. For the present pump, 2mm Decrease Bowl-Impeller axial gap model performs better comparably to the other models. It performs up to 2.35 % of efficiency from the existing model.

Keywords: Mixed Flow Pump, Submersible Pump, Best Efficiency Point (BEP), Moving Reference Frame (MRF), Bowl-Impeller Axial Gap, Computational Fluid Dynamics (CFD).

by Vivekanandan P., Arunachalam V. P.

Abstract - Aluminium based Hybrid metal matrix composite of varied weight percentage of tungsten carbide and fly ash have to be fabricated by stir casting method with acceptable uniform distribution of the reinforcement particles. A fair change in the hardness of the metal matrix composite is to be observed with increase in the WC content. Considerable increase in the hardness is expected to be observed with the addition of 5% weight of Fly ash and as the content of the Fly ash increased, the hardness tends to drop in the AMC .The tensile strength of the AMC is expected to increase with the increase in weight percentage of WC. With the addition of 10% weight of Fly ash to MMC, there could be improvement in tensile strength .The mechanical properties (Tensile Strength; Hardness) of the hybrid metal matrix composite were comparatively less to that of the AMCs. The SEM image will also to be incorporated to ascertain that both WC and Fly ash particles are well distributed in the AMC. From this research it is to be arrived to a conclusion that whether Tungsten Carbide and Fly ash can be used for the production of composites replacing the high cost aluminium alloy (7075).

Keywords: Al 7075, WC, Flyash, SEM, Tensile Strength, Hardness.

by S. Dharmalingam, P. Marimuthu, K. Raja, C. Nithyapathi, B. Babu, M. Siva

Abstract - Micro Electro chemical machining manufacturers and users are to achieve a better stability and high economical productivity of the manufacturing process is the main objectives of this investigation. This paper investigates the influence of the process parameters like machining voltage, electrolyte concentration, frequency on the over cut and Material Removal Rate (MRR). This paper discusses a methodology for the optimization of the machining parameters on drilling of Al-SiCp Metal Matrix composites using Electrochemical Micro Machining (EMM). The taguchi L27 orthogonal array and analysis of variance are employed to study the influence of machining parameters such as machining voltage, Electrolyte concentration, Frequency on the over cut and Material Removal Rate (MRR). Based on the Taguchi analysis, optimum level of parameters is determined and the same to validate through the confirmation test. Experimental results are in close agreement with the developed model. It is observed that the machining performance can be effectively improved with respect to initial parametric setting.

Keywords: Metal Matrix Composite (MMC), Material Removal Rate, Overcut, Electrochemical Micromachining (EMM), Taguchi, ANOVA, Design of Experiment.

by Mohd Amirul Abdul Rahman, Munaim Ali Omar Baki, Azmin Shakrine Mohd Rafie, Renuganth A/L Vartharajoo

Abstract - The material mechanical properties of coir fibre/epoxy composite were evaluated. High increase in consumption of coconut fruit for food processing and other industrial usage nowadays lead to increase in th production of coconut trash in the form of coir fibre. These coir fibres mostly disposed as unwanted waste since there are not much further applications to utilize the coir fibres. Furthermore, the aerospace industries currently are looking for more to optimize the performance of the existing materials (e.g. metal and synthetic fibre composite) that would be introduced in aircraft structure which relatively cut the cost in production, maintenance, and in-service aircraft, eco-friendly, and low in weight factor. Therefore, natural fibre reinforce composite might be recommender answers to solve these existing problems whereby this solution already been introduced in the automotive and civil application. The existing raw coir fibres used are in the form of pressed mat and originally in the random oriented fibre form. They have been used directly in the compression moulding process together with different fibre weight ratio of 20% to 50% with epoxy resins under room temperature and controlled pressure for composite fabrication process. The fibres underwent no modification at all. Then the fabricated panels have undergone mechanical material tests; tensile, flexural and torsion test with accordance to ASTM standard to obtain mechanical properties of the material including tensile strength, tensile modulus and shear modulus. These properties data will be recorded and might be used for further analysis such as aeroelastic analysis. The results shown the composite with the higher fibre percentage being more flexible (higher tensile strength) and less than 50% of fibre loading, rigid composites were obtained.

Keywords: Coconut Coir Fibre, Material Mechanical Properties, Natural Fibre Composites, Epoxy Resin, Random Oriented Fibre Composite.

by Dimitrios-Periklis A. Giannoulis, Dionissios P. Margaris

Abstract - Maritime accidents that can lead to major environmental pollution occur regularly. A simple system based on the fact that oil does not dissolve and is of lower density than sea-water, is proposed. The leaking oil is collected by a dome and it relies on gravity to channel the flux of oil along with sea-water, through a long riser tube to the sea surface, forming a two-phase buoyancy driven flow. A parametric axisymmetric CFD study is carried out in order to examine the solution of injecting air in the two-phase buoyancy driven oil-water flow, to avoid the formation of regions with single-phase flow of oil that can lead to flow blockages in the riser tube of the system. The present analysis studies the dome and the first 20 m of the riser tube. Computed distributions of flow regimes developed as well as radial mixtures velocities and flow pattern maps for the studied cases are presented.

Keywords: Maritime Accident, Leaking Oil, Numerical Simulation, Dome, Riser Tube, Three�Phase Flow.

by A. �iliukas, M. Kukis

Abstract - The article analyzes advantages of cellular constructions compared with constructions from monolithic materials. Strength and stability analysis of cellular cylinder is being carried out by using numerical method. Cellular cylinders in various sizes are being analyzed. Research showed that V-shaped cylinders have the greatest sustainable capability. The strength and stability analysis was carried out, results of geometrical dimensions of cellular cylinders were obtained, which are important in the production of construction elements of high technologies. In the application of cellular contsructions, it is possible to produce lightweight, multifunctional constructions and to select suitable materials to ensure the sustainable capacity and economy.

Keywords: Pressure Vessel, Sandwich Plate, Stability, Strength, Cellular Core.

by M. Tamani, B. Bahrar, K. Gueraoui

Abstract - This study provides a theoretical and numerical modeling of transient vaporous cavitation in a horizontal pipeline, anchored to the upstream reservoir. The model approach is, essentially, based on that of the column separation model (CSM). The basic system of partial differential equations to solve is a hyperbolic type and adapts perfectly to the method of characteristics. This code, allows us, taking into account the unsteady part of the friction term, to determine at any point of the pipe, and at each instant, the average piezometric head, the average discharge and the change in volume of the vapour cavity. This study illustrates the effect of the presence of air pockets, resulting in cavitation, on the amplitude of the pressure wave. The calculation results are in good agreement with those reported in the literature.

Keywords: Cavitation Model, Column Separation Model of Vapour, Method of Characteristics, Transient Flow, Unsteady Friction Model, Vapour Pressure Head.

by K. Arul Raj, M. Karthikeyan, R. Mariappan, S. Sakthisubaraja, A. S. Akilan

Abstract - Taguchi method has been a successful technique in improving the product quality and process performance for the past couple of decades. The present study optimizes the wearing rate of AISI 202. Since the price of nickel is so high, low nickel or non-nickel grade stainless steel is recommended to design the product. Dry sliding wear test was conducted to understand the wear and friction characteristics of samples. The tests were carried out in a purpose built-in vacuum pin-on-disc tribometer capable of testing the material up to a temperature 1000˚C and in vacuum. Relationships between the weight loss and applied load, time in seconds and friction coefficient were established. It was observed that reduction in the applied load reduces the friction factor and reduction in load reduces the weight loss. Also, the friction coefficient reduces when temperature increases, for all the parameters considered. The design of experiment approach was employed to determine the optimal combination of the testing parameters in a controlled way using Taguchi method for minimum wear rate. An orthogonal array and signal-to-noise ratio were employed to investigate the wear behaviour of AISI 202. The confirmation test was conducted to verify the experimental results. SEM images have been taken for certain wear specimens and the observations have been reported in this paper. The morphology of the worn surface was examined using scanning electron microscope and the micro-structure of the sub surface is also studied. It is observed that at temperatures above 400˚C, this material exhibits adhesive wear and the evidence of self-welding of mating parts has been observed in microstructures. It is also observed that the SS202 undergoes shear deformation during sliding wear.

Keywords: Wear, Elevated Temperature, SEM, Tribo-Graphs, Micro-Delamination, Taguchi Method, Orthogonal Array, S/N Ratio.

by M. Sivakumar, P. Somasundaram, P. Thangavel

Abstract - To Rule out the CFC�s from Vapour Compression Refrigeration, the Zeotropic mixture of HC�s and HFC�s being the only alternates to cater to the needs of Cryo-cooling and Cryo-chamber technology, the Three Component Zeotropic Mixture of R1270/R170/R14 was studied for the existence of the 3 stage ARC system. Exergy Analysis was carried out on this system for Confirmation of the 3 stage ARC System and the results confirmed the Existence of the system. The effect of mass fraction on Coefficient of Performance (COP), Exergy lost, Exergic efficiency, Efficiency defect and the Evaporating temperature achieved were investigated for different mass fractions. In accordance with the Environmental issues and the process of sustainable development, the Three Component Zeotropic Mixture of R1270/R170/R14 with the mass fraction of 0.265:0.18:0.55 was performing best with the suggestion of an alternative refrigerant for Three stage Auto Refrigerating Cascade (3 stage ARC) System operating at Very low evaporating temperature in the range of 183K (-900C) at COP of 0.267 and comparatively increased Exergic efficiency up to 6.02% (66.9%). The better performance with COP of 0.316 and the Exergic efficiency of 63.1% at around 194K (-790C) have eliminated based on the fact that the lower most evaporating temperature was not achieved..

Keywords: Exergy Analysis, Exergic Efficiency, Efficiency Defect, 3 Stage ARC, Zeotropic Mixture of R1270/R170/R14, Performance Analysis, COP.

by Anupam Dewan, Siddharth Gupta

Abstract - A computational study was carried out to optimize the positions of outlet strands and to compare the operating parameters of two-strand, four-strand and six-strand tundishes. This involved adoption of an Euler-Lagrangian approach to track spherical particles in a steady, three-dimensional flow field obtained by the numerical solutions of Reynolds-averaged Navier-Stokes and energy equations. The standard k-ε model and random walk model were used for modeling the turbulence in flow field and paths of inclusions, respectively. For comparison of different tundishes, two methodologies were adopted, first with equal mass flow rate of liquid steel at the inlet gate for all the tundishes considered (i.e., same capacity) and the second with equal mass flow rate of liquid steel leaving through each outlet strand for all the tundishes. It was found that for different tundishes with the same capacity, a change in the number of outlet strands does not have any significant effect on the operating parameters of the tundishes. For the tundishes with the same flow rate at each strand, the removal efficiency of two strand tundish was found to be more compared to that of four-strand and six-strand tundishes.

Keywords: CFD, Euler-Lagrangian Method, Particle Tracking, Multi-Strand Tundish, Turbulence.

by P. Kah

Abstract - Aluminum and its alloys, due to the characteristic features of aluminum like low density, good strength, ductility, corrosion resistance, and high thermal and electrical conductivities, are being used in a wide number of industrial applications, and the welding processes for aluminum are being automated for high-scale manufacturing. However there are some difficulties associated with the welding of aluminum for different welding processes. This work aims to describe and compare various methods for the automated fusion welding processes of aluminum alloys. It is almost exclusively made by reviewing several research articles and literature and discusses about the fusion welding process for aluminum alloys, its benefits, drawbacks, and usual applications. The most usual defects generated by these processes are also the target of this analysis. Two comparison tables are also presented and commented on, one comparing the features of each type of welding process and the other on comparing quantitative parameters, like the welding speed and weld type, as well as the quality of the weld, from various real world applications. It was found that the automated welding of aluminum is a well-established subject and that solutions for most industrial automated aluminum welding needs can be further explored.

Keywords: Aluminum, Automation, Sensor, Hybrid Laser Arc Welding.

by K. Rajeswari, S. Lavanya, P. Lakshmi

Abstract - This paper presents a Modified Grey Fuzzy Logic controller for enhancing the ride comfort and road holding ability of Vehicle Suspension System (VSS) simultaneously. Grey Prediction algorithm is used to pre-compensate the error. The prediction error in Grey Model (GM) is minimized by changing the initial condition and optimizing the weight factor in the data matrix of grey prediction algorithm. The aim of this paper is to design two Traditional Fuzzy Logic Controllers (TFLC), one for minimizing the sprung mass displacement error and the other for tyre deflection error. TFLC uses the grey model to design Grey Fuzzy Logic Controller based VSS. Particle Swarm Optimization (PSO) is used to optimize the weighting factor of grey model. The proposed controller is simulated for a Quarter Car model of VSS. Simulation results show that the proposed controller enhances both ride comfort and road holding ability simultaneously.

Keywords: Grey Prediction Algorithm, Particle Swarm Optimization, Quarter Car Model, Ride Comfort, Road Holding Ability.

by M. Lahbari, H. Benmoussa

Abstract - During this work, drying tests of carrot discs arranged in a thin layer on a fixed bed were carried out on a hot air dryer. This study was limited to the influence of the air temperature for the dehydration of these washers without any pretreatment. The experiments were performed for two temperatures: 50 and 70 � C at an air speed of 1m/s while performing other experiments for air speeds and different forms of cutting in order to compare the results. It turned out that the drying air temperature controls most of the drying process of this food.

Keywords: Carrot Washers, Cut Form, Convective Dryer, Water Content, Kinetic Drying.

by A. Kumaravelu, C. Jegadheesan, C. Senthilkumar

Abstract - Electrochemical machining (ECM) has been increasingly recognized for the potential of machining, while the precision of the machined profile is a concern of its application. This paper describes the development of a second order, non-linear mathematical model for establishing the relationship among machining parameters such as applied voltage, electrolyte flow rate and tool feed rate with the dominant machining process criteria, namely material removal rate (MRR) and overcut (O.C). The model is developed based on response surface methodology (RSM) using the relevant experimental data, which are obtained during an ECM operation. The results of analysis of variance (ANOVA) indicate that the proposed mathematical model obtained can adequately describe the performance within the limits of the factors being studied. The contour plots are generated to study the effect of process parameters as well as their interactions.

Keywords: Electro Chemical Machining (ECM), Response Surface Methodology (RSM), Metal Removal Rate (MRR), Overcut (O.C).

by P. Jaganathan, Sivasubramanian, V. Krishnaraj

Abstract - This research work is focused on hard turning of AISI M2Steel using Cubic Boron Nitrate (CBN) cutting inserts. The experiments were planned using Response surface method (RSM) called Central Composite Design (CCD) procedure. The experiments were performed on a KIROLOSKAR model centre lathe using three input cutting parameters ,cutting speed, feed and depth of cut at lower levels(-1) and higher levels(+1). The output responses measured were surface roughness (Ra) and tool life (TL) .Mathematical model for these responses were developed using response surface methodology (RSM). An optimal process condition was identified such that to attain a good quality of hard turned surface. Models were developed using two methodologies, ie. response surface methodology (RSM) and fuzzy Logic (FL). In RSM, regression equations are obtained, which relates the hard turning parameters with each response. The adequacy of the model was checked using R-squared values. The response values predicted by developed model were compared against the experimental values and found that they are in good agreement with each other. In fuzzy logic, with the range of input machining parameters and if then rules, output response parameters are obtained and verified against the experimental values and found that they are also in good agreement with the each other. Triangular type membership functions of fuzzy logic were used in this study. Then both the methodologies were compared with the experimental values and best method was identified for modeling to achieve a better result. Then the interaction effects of various hard turning parameters on each response were also studied using analysis of variance (ANOVA) and interaction plots. Genetic algorithm(GA) was used to identify the optimal hard turning parameters in such a way to produce a good quality machined surface in hard turning AISI M2Steel using CBN(non coated) cutting tools.

Keywords: AISI M2 Steel, CCD, Fuzzy Logic, Genetic Algorithm, Hard Turning, RSM.

by L. Jayakumar, K. Balamurugan, C. Ezilarasan

Abstract - The wear and friction behaviour of 7075 Al-25(wt %) SiC particle composite were investigated at a speed range of 3 to 9 m/s and load range of 30 to 110 N using pin-on-disc wear testing machine. In this work, the automobile friction material was used as pin and the composite as counter face and the results were compared with the commercially used cast iron brake disc. The results show that the wear rate of the Al MMC disc was less than that of the conventional cast iron disc. The coefficient of friction decreases with increase of applied load for both cast iron and Al MMC materials. However, the friction coefficient of Al MMC is higher than that of the cast iron. In all tests it is observed that the wear rate of friction material was more when sliding against MMC disc because of the abrasive action of fractured and pulled out SiC particles. The wear grooves formed on the cast iron disc, MMC disc and friction material have been analysed using optical micrographs and X- ray diffraction (XRD) technique.

Keywords: Metal Matrix Composites (MMCs), Wear, Optical Microscopy, Stir Casting.

by Hany A. El Kadi, Ibrahim M. Deiab, Amal A. Khattab

Abstract - Due to the increased calls for environmentally benign machining processes, there has been more focus and interest in making processes more lean and agile to enhance efficiency, reduce emissions and increase profitability. One approach to achieving lean machining is to develop a virtual simulation environment that enables fast and reasonably accurate predictions of machining scenarios, process output, and provide access to needed information. This paper investigates the utilization of artificial neural networks (ANNs) to predict the cutting forces resulting from various combinations of cutting parameters and can also provide values for the cutting coefficients usually predicted to calibrate the force models. Predictions are compared to measured experimental results obtained and are shown to be in good agreement.

Keywords: Cutting Forces, Cutting Coefficients, Artificial Neural Networks, Mechanistic Model, Face Milling.

by N. A. Mazalan, A. A. Malek, Mazlan A. Wahid, M. Mailah

Abstract - Main steam temperature is one of the most important parameters in a coal fired power plant and its characteristics are non-linear and having large inertia with long dead time. Successful control of main steam temperature within � 2 deg C from its setpoint is the ultimate target for the coal fired power plant operators. Two of the most common main steam temperature circuit are primary superheater spray and secondary superheater spray. This paper present the primary superheater spray control valve modeling based on Levenberg-Marquardt learning algorithm. The neural network algorithm will be trained using actual plant data. The result of the simulation showed that the primary superheater spray control valve modeling based on neural network with Levenberg-Marquardt learning algorithm is able to replicate closely actual plant behavior. Generator output, main steam flow, total spraywater flow and secondary superheater outlet steam temperature are proven to be the main parameters affected the behavior of spray control valve opening in the unit.

Keywords: Main Steam Temperature, Primary Superheater Spray, Neural Network, Levenberg-Marquardt Learning Algorithm.

by A. Jebelli, M. C. E. Yagoub, N. Lotfi, Seyyed Hossein Kazemi Riabi

Abstract - In this paper, a fuzzy logic-based control system is proposed, which lays emphasis on the functionality of the system rather than developing a mathematical model. Applied to an arm robot, it can achieve precise motion control along with power consumption minimization. Dynamic equations of the physical modeling of a two-arm planar robot were first derived and then a Proportional-Integral (PI) fuzzy logic controller was designed to maintain a desired trajectory of motion. Numerical results show promising performance since the proposed PI-type fuzzy logic controller can be used for trajectory tracking of dual-arm robots during safely load transportation tasks.

Keywords: Arm Robot, Dual-Arm Robot, Fuzzy Logic, PI, PID, PWM.

by Musthafah M. T., Safarudin H., R. A. Bakar, M. A.Salim, A. M. Mohd Shafie

Abstract - To mitigate the world�s energy problems and global warming, researchers are focusing on renewable energy, regenerate energy, efficient energy usage and finding alternative energy. In an automobile, Internal Combustion Engine (ICE) also produces heat which is released as waste heat which have a potential to generate energy. Power distribution of an automotive is showing that only about 20% of the power from engine combustion is convert to wheel or driving power and more than 60% of the power will be wasted. One way to convert heat to useful work is by using Rankine cycle. Research study to described the effects of thermal properties of an organic working fluid on the turbine power had also been reported. This research is to investigate the actual potential energy and power from the waste heat released by the an actual passenger car�s ICE through radiator. Feasibility study is conducted, to investigate the capability of the system and to help developing a system that can be used in an actual automobile. With the collected data, an efficient waste heat recovery system for the passenger car�s engine will be develop in the future. From the experiment result, the power output up to 800 W from heat released in the radiator as the temperature difference about 35 (C (heat in and out difference). From this study, it is found out there is a significant problem when the radiator cooling fan operates. The power from the waste heat intended to reduce and also becoming unstable. A power storage system and the radiator cooling fan control will be vital to obtain high usable energy from ICE heat.

Keywords: Energy Recovery, Rankine Cycle, Waste Heat, Potential Power, Engine Radiator .

by Paul Kah, Esa Hiltunen, Raimo Suoranta, Jukka Martikainen

Abstract - Robotic welding is commonly viewed as one of the most effective ways to reduce costs and increase competitiveness in welding production. However, several requirements need to be taken into account when exploiting welding robotics. The main issues to be considered are the construction of the item to be welded, for example, the joint types, and accessibility to weld sub-assemblies such as stiffeners and cross supports. Furthermore, the type of base material places some restrictions upon the sensing technology applied. This work studied the robotic welding of an aluminum boat. Several sensor technologies were examined and welding experiments undertaken to clarify their potential. Redesign of sub-assemblies of the aluminum boat through modularization and selection of suitable welding processes for aluminum welding are found to provide the optimal solution for the adoption of sensor guided robotic welding.

Keywords: Aluminum Welding, GMAW, GTAW, Optical Sensing, Real-Time Sensing, Robotic Welding, TAST.

by S. Men-la-yakhaf, K. Gueraoui, , A. Maaouni, M. Driouich

Abstract - The main objective of this study was to improve the management of bioreactors, existing or in the future. We have studied the thermo-hydro-biological behavior of waste in the anaerobic phase. For this, we have presented the equations of conservation of matter and of energy and the thermodynamic functions. We have developed a numerical model to simulate the coupled behavior of bioreactors, using the finite volume method.

Keywords: Waste, Anaerobic Phase, Numerical Model, Reactive Mass Transfer, Heat Transfer.

by M. S. A. Ishak, M. N. M. Jaafar

Abstract - The main purpose of this paper is to study the internal flow effect of varying the swirl number inside the combustor. The flow field inside the combustor is controlled by the liner shape and size, wall side holes shape, size and arrangement (primary, secondary and dilution holes), and primary air swirler configuration. Air swirler adds sufficient swirling to the inlet flow to generate central recirculation region (CRZ) which is necessary for flame stability and fuel air mixing enhancement. Therefore designing an appropriate air swirler is a challenge to produce stable, efficient and low emission combustion with low pressure losses. Four radial curve vane swirler with 30o, 40o, 50o and 60o vane angle corresponding to swirl number of 0.366, 0.630, 0.978 and 1.427 respectively were used in this analysis to show vane angle effect on the internal flow field. The flow behavior was investigated numerically using CFD solver Ansys 14.0. This study has provided the characteristic insight into the flow pattern inside the combustion chamber. Results show that the swirling action is augmented with the increase in the swirl number, which leads to increase in the turbulence strength, recirculation zone size, and amount of recirculated mass. The current study report that the 50� swirler (swirl number > 0.7), produced enough swirling flow to generate good CRZ in the combustion chamber.

Keywords: Swirler, Swirl Number, Combustor, Turbulence, CFD Simulation.

by M. M. Noor, Andrew P. Wandel, Talal Yusaf

Abstract - The future of today's society is greatly depending on the energy development. Due to the depletion of fossil fuel and the gradual development of energy generation from renewable sources, energy security becomes an important intergovernmental issue. This paper discusses the energy needs and the new combustion technology that will aid in achieving lean and clean combustion. In 2001, British Petroleum estimated the total natural gas reserves to be 187.5 trillion cubic meters, which can supply up to 7�10¹⁵ MJ of energy. The total petroleum reserves can supply up to 1,383 billion barrels which amounts to 8.4�10¹⁵ MJ of energy. Due to the increasing population and economic development, these fuel reserves will not last long. Energy efficiency and greenhouse gas emissions are two important and critical issues. The new combustion technology, moderate and intense low oxygen dilution (MILD) combustion provides a feasible solution. MILD, also known as flameless oxidation (FLOX) and high temperature air combustion (HiTAC) was discovered by W�nning in 1989. The thermal efficiency of combustion can be increased by about 30% and NOx emission reduced by 50%. MILD also can be achieved using different types of fuel such as gas fuel, liquid fuel and industrial waste fuel (saw dust). MILD combustion will be an important future combustion technology due to it producing higher efficiency and very low emissions.

Keywords: Energy Security, MILD Combustion, Biogas, World Energy Policy.

by Noor Hafizah Amer, Rahizar Ramli, Wan Nor Liza Wan Mahadi, Mohd Azman Zainul Abidin, Hazril Md Isa and Soong Ming Foong

Abstract - In the past few decades, researchers have been focusing on improving control strategy for automotive active suspension system. There are few configurations used in active suspension mechanism and one of them is Electromagnetic Suspension (EMS) System. In this study, the implementation of a Linear Quadratic Regulator (LQR) controller in an EMS System for vehicle Active Suspension System (ASS) was investigated. This provides an optimal control solution for the active suspension system. Quarter vehicle model of an electromagnetic suspension was derived and employed to study the implementation of the LQR controller. Detailed parametric analysis for the proposed controller and implementation results will be presented in this paper. This is done by investigating the effect of weighting parameters in the performance index of the optimal control strategy in stabilising the vehicle response. The controller�s performance was compared against a passive suspension system based on a commercial passenger�s car. Parametric analyses revealed the importance of weighting parameters in the optimal control formulation. Finally, it was proven that LQR controller strategy provides a satisfactory improvement for the EMS system compared to passive suspension performance.

Keywords: LQR Controller, Electromagnetic Suspension, Active Suspension.

by M. R. Abdullah, C. L. Pang, N. A. Husain, B. Abdi

Abstract - This paper deals with experimental investigations of fibre metal laminates (FMLs) based on kenaf/epoxy under static indentation loading. Tests were conducted on 2/1 lay-up and 3/2 lay-up of FMLs that fabricated by using vacuum infusion process and hydraulic pressing technique. Indentation tests of FMLs were conducted with loading rate of 10 mm/min. The front and rear surfaces of indentation-loaded FMLs were examined to identify the failure mechanisms at different configurations. It was found that, the failure was happened on the surface of pure kenaf by increasing the indentation depth. However, debonding between the aluminium sheet and kenaf/epoxy is occurred only for 3/2 lay-up of FMLs. The contact force-displacement curves and energy absorption-displacement curves were analysed. The resistance to deform and damage was increase by increasing the number of layers and thickness of aluminium alloy sheet.

Keywords: Failure, Fibre Metal Laminates, Indentation, Kenaf, Vacuum Infusion.

by Anika Zafiah M. Rus, Siti Rahmah M., Shaiqah M. Rus

Abstract - This study reports on the effect of UV-light on the FTIR spectra of bio polymer doped with 10 % TiO₂ (BPF1.0) in a gas cell full with nitrogen gas (N₂) and a droplet of water (H₂O). The film samples were put in the 10 cm NaCl gas cell with 99.99 % N₂ with H₂O at different exposure time of 40 �C. An unexposed gas cell fill with N₂ and H₂O is used for the purposed of comparison. The chemical structural changes in the UV irradiated gas cell were monitored by Fourier-transform infrared (FTIR) spectroscopy methods. The changes in hydroxyl, (OH) and carbon nitrogen double bond, (C=N) of bio polymer doped with TiO₂ under UV exposures were discussed. OH and C=N intensities decreases of exposed to UV light under N₂ with H₂O in gas cell. The UV-radiation shows FTIR spectrum changes on BPF1.0 of exposed to nitrogen gas and water.

Keywords: Bio Polymer, Nitrogen (N2), Water (H2O), Gas Cell, UV Light, FTIR Spectra.

by A. H. Zakiah, N. Jamaludin, J. Syarif, S. Y. S. Yahya

Abstract - Currently the tube inspection technologies are normally invasive and time consuming, and therefore, an effective and non-invasive tube inspection method is required. This paper presents the research works on the development of non-invasive and non-destructive defect detection system and analysis for the ASTM A179 seamless steel tubes. Vibration excitation using impact hammer method is used to generate transient stress waves in steel tubes. Specifically, three steel tubes were used including a good steel tube and two steel tubes with through-hole artificial defect at different locations. An acoustic emission technique is utilised to detect and capture the stress waves propagation in the steel tubes. The variations of the stress waves propagated in the different condition of the steel tubes were successfully characterized and differentiated using three conventional statistical features namely root mean square (r.m.s), crest factor and kurtosis. The acquired experimental results show that the newly proposed Vibration Impact Acoustic Emission (VIAE) method is capable of detecting the presence of defect in the steel tubes.

Keywords: Defect Detection, Non-Invasive Inspection, Impact Excitation, Stress Wave .

by Kumaran P., Saifuddin N., Janarthanan S.

Abstract - Biodiesel production from microalgae has attracted major interest recently as a renewable energy which is capable of reducing the effect of global warming at same time provide sustainable energy source. This study determines the potential of microalgae species, Tetraselmiss chuii lipid as a biodiesel feedstock. Fatty acid profiling of the biodiesel, obtained from T.chuii lipid showed higher content of saturated fatty acids (SFA) 50.1% than monounsaturated fatty acids (MUFA) 31.6% and polyunsaturated fatty acids (PUFA) 17.5%. The biodiesel produced was also characterized in terms of kinematic viscosity, cetane number, iodine value, degree of unsaturation and higher heating value. The quality of the biodiesel produced from T.chuii lipid were a kinematic viscosity of 3.2 mm²/s, a cetane number of 63.7, an iodine value of 59.3 g I₂/ 100g^-1, a degree of unsaturation of 66.6% and a higher heating value of 41.3 MJ/kg. The result obtained from this study indicated that the biodiesel produced from T.chuii lipid complies with the US Standard (ASTM 6751) and European Standard (EN14214).

Keywords: Global Warming, Renewable Energy, Biodiesel, Microalgae.

by M. Ishak, A. Amir, A. H. Ahmad

Abstract - Over the years, aluminum content in a vehicle part is increasing due to the needs to reduce weight as well as increase fuel efficiency. Most of the cast product in a vehicle part is mostly cast from A356 alloy. It is used because A356 alloy posses� excellent characteristics over other type of alloy such as cas ability, high strength to weight ratio, good corrosion resistance and good weldability. Most of the cast component in vehicle such as cylinder head favors hardness over tensile strength. Most of the solution treatments studied was done on sample having α-Al with dendritic structure. The objective of this research is to investigate the effect of solution treatment temperature on microstructure and mechanical properties of A356 (Al7Si0.3Mg) aluminum alloy. Heat treatment was done to harness the full potential of cast A356 alloy and T6 heat treatment is the commonly used treatment for this alloy. In the present study, the specimen was cast using low pouring temperature method which produces equiaxed α-Al structure. The specimen undergone solution treatment for two (2) hours at three different temperatures (530 �C, 540 �C, and 550 �C), quenched in water at room temperature, followed artificial aged for six (6) hours at 170 �C. Mechanical properties of A356 aluminum alloy were investigated by tensile test and hardness test. The relation between size, shape, and distribution of Si particle and the alloy�s mechanical properties were investigated. Si particle size, shape, and dispersion affect the mechanical properties of cast A356 alloy. Higher solution treatment temperature produce smaller and more globular Si particle before completing T6 heat treatment. Elongations decrease while ultimate tensile strength (UTS) increase as solution temperature increased from 530 �C to 550 �C. A356 aluminum alloy specimen solution treated at 530 �C have comparable hardness compared with specimen solution treatment at 540 �C before and after artificial ageing - complete T6 heat treatment - with higher elongation and lower energy usage as added benefit.

Keywords: Solution Treatment Temperature, Equiaxed Α-Al, Hardness, A356 Aluminum Alloy.