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Abstract - In recent decade, more stringent laws have been ordained to cope with environmental issues and global warming. Industrial sectors have been urged to substitute new combustion methods to decline their emissions, but the cost of pollutant reduction in traditional combustion is efficiency abatement. In the other word, emission and fuel consumption cannot be declined simultaneously by conventional combustion. High temperature air combustion (Hitac) is an innovative substitution for conventional combustion which has been developed to increase combustion efficiency and to decline pollutant formation contemporaneously. Recently, some valuable experimental and numerical analysis have been done to study the variety aspects of Hitac and to study the reasons of the compatibility of high efficiency and low NOx production in Hitac area. The outstanding characteristic of Hitac is its sustainability under low oxygen concentration when the combustion air is preheated more than the fuel auto-ignition temperature. Therefore, it can be observed that thermal NOx is suppressed due to lack of oxygen concentration. This paper is concerned with NOx formation reduction in Hitac systems via physical and chemical analysis. Chemical kinetic, heat transfer concepts, simulation studies and experimental investigations have been employed to analyze NOx formation mitigation in Hitac method.

Keywords: Hitac, NOx Formation, Preheated Air, Dilution, Flame.

Resolution of an Inverse Problem in Thermal Diffusion Process for the Identification of a Heat Flux
by Abdelkarim Maamar, Touhami Y., Bounegta B., Khadir M.

Vol. 6 n. 5, pp. 954-958

Abstracts – In this work we propose a temporal determination of a heat flow, within a diffusive 2d linear medium with resolution of an opposite problem. Here 2 different methods of resolution are suggested and a comparison between the two is made. Regarding the first method of inversion that is based on a convolution integral for that it is necessary first of all to solve the direct problem which requires the construction of the step responses and the temperature measurements using the finite differences method. In the reversal phase, the linear system is considered under the form of single-input (the flow to be identified), multi-output (temperature measurements). The 2nd method is the regularizing method of the combined gradient, where the direct problem with all the assumed known parameters has an analytical solution to be used as observation to estimate the unknown parameters with resolution of an inverse problem.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Linear Thermal Diffusion Process, Opposite Problem, Heat Flux, Convolution Integral, Combined Gradient, Finished Difference.

Energy Efficiency in the Ceramic Industry: Recovery Heat of Combustion of Smoke Oven for a Spray-Drayer
by V. Bristot, V. Bristot, L. Schaeffer, V. Gruber, J. Alves, J. Mangili, R. Tassi

Vol. 6 n. 5, pp. 959-965

Abstract – The expansion of the ceramic coating market in decades boosted the development and improvement of manufacturing techniques for many companies, resulting in a highly competitive market driven by low manufacturing costs. The Strategies to stay alive and even leading reference, are companies perform constant new product launches, by analysis of plans to reduce costs. It is known that the energy matrix of the ceramic tile industry Wet process corresponds approximately to the range of 22 to 30% of the composition manufacturing costs, where this percentage, about 37% of the consumption of thermal energy is directed to only one device, the spray-dryer. On the basis of these values in the last 10 years companies have maintained their focus directed to the strategic management energy efficiency, which depart from the principles cogeneration projects and recovery heat, to replace equipment with more efficient ones. The main objective this article is to demonstrate the planning, execution and outcome of a recovery project of heat from the flue gas scrubbing combustion furnace of a roll as an air dilution a spray-dryer in the coatings industry.

Keywords: Energy Efficiency, Furnace Rolls, Heat Recovery, Coatings Ceramic, Spray-Dryer.

Flow of a Second Order/Grade Fluid Induced by a Pull of Disks in an Orthogonal Rheometer Under the Effect of a Magnetic Field
by H. Volkan Ersoy

Vol. 6 n. 5, pp. 966-971

Abstract - The flow of a second order/grade fluid produced by a pull with constant velocities of disks in an orthogonal rheometer with the application of a magnetic field is studied. It is investigated the effect of the magnetic field exerted perpendicularly to the disks on the flow for both positive and negative values of the material modulus α₁. It is shown that the flow in the presence of magnetic field has thinner boundary layers than that in the absence of magnetic field. It is found that the y- component of the dimensionless force per unit area exerted by the fluid is greater than the x- component for all values of the Hartmann number M. Increasing the magnetic field causes an increase in the x- component but a decrease in the y- component for the elasticity of fluid with positive and negative sign. It is obtained that the x- component corresponding to α₁ > 0 is larger than that corresponding to α₁ < 0. An opposite effect is seen for the y- component.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Magnetic Field, Orthogonal Rheometer, Pull, Second Order/Grade Fluid.

Impact of Liquid Pressure Losses and Solid-Phase, in the Performance of a Three-Phase Flow Air-Lift Pump
by Dimitrios N. Androulakis, Apostolos N. Vlachos, Dionissios P. Margaris

Vol. 6 n. 5, pp. 972-978

Abstract - The aim of the paper is to present the results of an experimental investigation of a three-phase flow air-lift pump lab-scale installation. The existing lab-scale installation was modified, in order to create new potentials of further investigation concerning two new downcomers. In order to certify the installation, several experiments took place and the results were compared with former ones of the same conditions. Experiments were held in 28 mm and 40 mm diameter pipes with defined points of submergence ratio, gas flow rate and solid-phase mass. The impact of liquid pressure losses via a downcomer and the impact of the solid-phase are to be investigated. The measured points of three-phase flow are then presented on operational curves, concerning superficial velocities. Finally, experimental results are presented in a suitable flow regime map.

Keywords: Multi-Phase Flows, Air-Lift Pumps, Superficial Velocity, Operational Curves, Regime Map.

Design of Compliant Mechanisms by Topology Optimization for Strain Actuators and Engineering Support
by G. Arunkumar, J. Santhakumar

Vol. 6 n. 5, pp. 979-987

Abstract - Compliant mechanisms are the focus of active research because of the flexibility, stability and unitized construction. It is a single elastic continuum used to transfer the force and motion mechanically by elastic deformation without any links and joints. Authors proposed a topology optimization method for designing a compliant amplifier and the steps for conducting the numerical experiments for any shape of design domains with different types of constraint. The paper narrates the design of the compliant amplifier mechanism from the basic geometrical shapes using topology optimization which can be used for amplifying the output displacement of the strain actuators. Numerical experiments are carried out for different basic configurations to design the compliant amplifier. The compliant amplifier is used for amplifying the displacement and stroke performance of the strain actuators when integrated with piezo actuators. The objective is to maximize the geometric advantage of the compliant amplifier. The maximization of the geometric advantage is accomplished by efficient design of compliant mechanisms using the topology optimization approach. The analysis results help to select the best compliant amplifier design from the basic configurations. The outcome of this work will be useful for all types of strain actuators.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Compliant Mechanisms, Geometric Advantage, Topology Optimization, Numerical Experiments.

PID Controller Tuning for Magnetic Suspension System Using Evolutionary Algorithm
by V. Rajinikanth, K. Latha

Vol. 6 n. 5, pp. 988-995

Abstract - In this paper, a model based intelligent PID controller tuning is attempted for a Magnetic Suspension System (MSS) using Bacterial Foraging Optimization (BFO) algorithm. MSS is an Electro- Mechanical system with highly non linear dynamics and exhibits unstable steady state behavior around the nominal operating range. In this work, Integral Time Absolute Error (ITAE) based performance criterion is employed to guide the BFO to search the optimized controller parameters such as Kp, Ki, and Kd. The work is substantiated through a comparative study with Particle Swarm Optimization (PSO) algorithm by using PID and modified PID controller structure. The effectiveness of the proposed scheme has been validated with a simulation study and the results show that the proposed method provides better result in the control of the unstable MSS system with effective setpoint tracking and load disturbance rejection.

Keywords: Magnetic Suspension System, Unstable System, PID controller, Bacterial Foraging Optimization.

Optimization of Deep Drawing Process Parameters Using Design of Experiments
by J. Santhakumar, G. Arunkumar

Vol. 6 n. 5, pp. 996-1000

Abstract - Sheet metal forming is a technique by which most automotive body parts are produced in automobile industries. In sheet metal forming, a thin blank sheet is subjected to plastic deformation using forming tools to confirm to a designed shape. During this process, if the process parameters are not selected properly, the blank sheet is likely to develop defects. Optimization of process parameters in sheet metal forming is an important task to reduce manufacturing cost. The purpose of this investigation is to determine the optimum values of the process parameters. It is essential to find their influence on the deformation behavior of the sheet metal. Four process parameters are taken to optimize the deep drawing process, namely Plastic Anisotropy (R), Strain Hardening Coefficient (n), Tensile Strength (TS) and Friction Coefficient (µ). Numerical simulation is nowadays a modern engineering practice for sheet metal product and tool design developments using the finite element method. Present work examines the accuracy of numerical simulation results of deep drawing testing of steel sheets using the finite element software (Ls-Dyna) to reproduce the design of experiment (DOE). Three level and four factors are used in the DOE. Historically, sheet metal formability has been assessed by tensile testing and biaxial stretching such as the Erichsen simple test. Lately, the concept of experimental forming limit curve for strains, Forming Limiting Curve (FLC) and the numerical simulations were developed to evaluate sheet metal formability and it’s forming operations by predicting the onset of local necking and fracture. In the present work, we use ANOVA method to compute the influence and contribution of the above parameters.

Keywords: Deep Drawing, LS-Dyna, DOE, ANOVA, Numerical Simulation.

Finite Element Simulation and Experimental Evaluation on Superplastic Forming Process of Aluminium Alloy Sheet
by G. Kumaresan, K. Kalaichelvan

Vol. 6 n. 5, pp. 1001-1004

Abstract - Superplasticity is the ability of certain materials to undergo large elongation at the proper temperature and strain rate. This work focused on enhance superplastic behavior of Aluminium alloys 7075 by uniform thinning at reduced flow stress and optimum strain rate at constant temperature. The experiments were conducted to obtain a rectangular shaped superplastically formed component by varying process parameters such as strain rate, temperature and pressure. This work is made to explore the superplastic deformation behavior of the aluminium alloys 7075 into a rectangular shaped product by numerical simulation using standard finite element code ABAQUS. It is shown that the proposed optimization approach compares the characterics of deformation and failure during superplastic forming and to find suitable process parameters such as temperature, pressure and time for enhanced uniform thinning.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Finite Element Modeling, Superplastic Forming, Rectangular Box Forming, Thinning, Optimization.

Wall-Models for LES of Channel Flows
by Taieb Nehari, Lotfi Tefiani, Driss Nehari

Vol. 6 n. 5, pp. 1005-1010

Abstract - The present paper describes the analysis and the implementation of simple wall models for Large Eddy Simulations of high Reynolds numbers flows. The comparison with direct numerical simulation (DNS) in channel flow at Re_τ=950 was carried out. The results obtained from wall models compare well with numerical data.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Turbulent Flow, Large Eddy Simulation, Wall model, Channel.

Modelling of Centrifugal Compressor Impellers Using Adaptive Neuro- Fuzzy Inference Systems (ANFIS)
by Layth H. Jawad, S. Abdullah, R. Zulkifli, W. M. F. W. Mahmood

Vol. 6 n. 5, pp. 1011-1017

Abstract - In order to model the design parameters of centrifugal impeller it is necessary to find new method for design parameters prediction. Adaptive neuro- Fuzzy Inference System (ANFIS) was used to predict the design parameters. The geometry parameter definition system of radial impellers based on Bezier curves, a typical centrifugal impeller with an inlet and a radial outlet used in this paper comprises a series of three Bezier patches or segments. The hub and shroud blade sections are defined as distributions of camber line; Data were generated from Bezier curves equations. In this paper, is the use adaptive neuro-fuzzy inference systems (ANFIS) approach is developed a design prediction method for radial impellers, to use it as design parameters predictor of radial impeller angles. The results were compared by statistical criterion (RMSE). Considering the results, it is obvious that our proposed modeling by (ANFIS) is efficient and valid and it can be expanded for more general states.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: ANFIS, Centrifugal Compressor Impeller, Design Parameters.

Numerical Study of Heat and Mass Transfer in Membrane Distillation for Desalination of Seawater
by A. Rachdi, R. Sebai, F. Bouslama, R. Chouikh

Vol. 6 n. 5, pp. 1018-1024

Abstract - The present work investigates the heat and mass transfer mechanisms in a cross-flow parallel plate membrane distillation module. The three dimensional model which accounts simultaneously for heat and water transfer in the membrane and the channels. The results are compared to the available data and the agreement is satisfactory. The effect of operating parameters such aspect ratios of the rectangular ducts, volume flow rates, the temperature differences, the heat flux and the mass flux of water vapor are also investigated.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Heat Transfer, Mass Transfer, Membrane Distillation, Cross-Flow.

Supervision and Control Architecture Proposal for Automation and Robotics Training on Platform
by Ricardo A. Castillo, João M. Rosário, Oscar F. Aviles

Vol. 6 n. 5, pp. 1025-1034

Abstract - This work proposes a generic supervisory and command architecture for an experimentation modular automated platform equipped with remote access capacities which is conceived with the aim of improve training and research processes on Automation and Robotics, this study describes the platform´s design, dynamic modeling and implementation stages. The technologic and industrial devices integration (Programmable Logic Controllers - PLC, several types of sensors and actuators, image processing, supervisory systems and robotic manipulation devices) in a single platform which is implemented following a modular Collaborative Automatic Production System (CAPS/ADACOR) architecture allows students and researchers to interact with it by means of doing practices in order to successfully automate, supervise and manage a complete production process. Therefore, class acquired theoretical concepts are supported so improving user´s professional skills. A platform developed using the here proposed generic structure allows users to work within an educational environment coping with most of the encountered aspects in a real Manufacturing Automation System, such as Technologic Integration, Communication Networks, Process Control and Production Management. Furthermore it is possible to command the entire assembly process taking place at the platform by a remote network connection using the internet – WEBLAB (Remote Laboratory), enabling individual users and groups in different places in order to use the platform and quickly interchange information. In addition it is important to outstand that both the Modularity and Flexibility of the platform can allow readily any further hardware or software enhancement.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Collaborative Automation, Integration Architecture, Process modeling, Robotics.

Injector Nozzle Spray on Compressed Natural Gas Engines: a Technical Review
by Semin

Vol. 6 n. 5, pp. 1035-1043

Abstract - In this article, previous work on the application of injector on CNG engines is reviewed. In the review of injector, the spray characteristics, the gas jet structure, the effect of injector nozzle geometry on fuel-air mixing, injector nozzle coefficients of discharge, injector nozzle spray tip penetration and cone angle as well as injector nozzle orifice shapes are outlined. Fuel-air mixing increases as the orifice diameter decreases. This can be a significant advantage for small orifice nozzles. However, multiple orifices are required to meet the desired mass flow rate as orifice diameter decreases.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Fuel-Air Mixing, Gas Jet Structure, Injector Nozzle, Nozzle Orifice Shapes, Spray Characteristic.

Design and Development of Camless Valve Train for I.C. Engines
by R. Shriram, M. Mari Ram Kumar, T. Vignesh Aadhithya, B. Vijaya Ramnath

Vol. 6 n. 5, pp. 1044-1049

Abstract - An indispensable mechanism in the valve train of an internal combustion engine, right from the one developed by Nicolas August Otto (in 1876) to the present one, is the cam and follower mechanism. For years, many ideas have been proposed on alternative valve trains and so do we propose one such idea on camless valve train. The idea employs a simple valve train mechanism through rotating discs, timing gears and shafts that connect them. Based on the valve timing calculations, a sweep profile sized to the port diameter is cut in the disc such that it serves a purpose analogous to the valves in the conventional system. The mechanism is actuated by conveying the rotational motion of the crankshaft, to the discs by employing a bevel gear drive, thereby eliminating the frictional loss in cam-follower interface.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Camless Valve Trains, Discs, SPCA-Sweep Profile Cut Area, Valve Timing, Valve Angle.

An Analytical Investigation of Overall Thermal Transfer Value on Commercial Building in Malaysia
by M. F. Sukri, M. A. Salim, M. A. Mohd Rosli, S. B. Azraai, R. Mat Dan

Vol. 6 n. 5, pp. 1050-1056

Abstract - This paper investigated analytically the Overall Thermal Transfer Value (OTTV) of selected commercial building with respect to standard. The building specifications have been identified through site audit visit and OTTV are calculated based on equations developed by open literature. The OTTV then being compared to standard value proposed for local climate. New building materials and specifications were proposed when the OTTV value is out of the standard range. The results shown the current OTTV is 90.2% higher that proposed value for standard commercial building. It suggested considering silver coloured at West pre-cast concrete wall, 12 mm single monolithic clear glazed glass for all windows at North and South elevations and double glazed glass for all windows at East and West elevations. In addition, 900 mm horizontal sun shading device for all windows at ground level and 700 mm for remaining floors are also needed, except for windows at West pre-cast concrete wall. By doing so, the OTTV reduced to 47.43 W/m2. Since air-conditioning is major energy usage of total typical commercial building energy consumption, reduction on OTTV will slightly dropped air-conditioning cooling load and possibly, lowered building energy intensity index (BEI) to the range of energy efficient building practice.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: OTTV, WWR, Commercial Building, Energy Efficient Building.

Analysis of a Diesel Engine with Developed Multi-Zone Combustion Model by Considering Heat Transfer between Zones
by Reza Akbarpour Ghiasi, Yahya Ajabshirchi

Vol. 6 n. 5, pp. 1057-1067

Abstract - In current study, the Cummins engine multi-zone combustion model (a simulation model of diesel engines) is developed and compared with the older model and also with the associated experimental data. This development is performed by reforming in heat transfer calculations. The reforming process is done by considering heat conduction between the next zones, heat radiation in burning zones and heat convection in air zone. Also, the developed model contains sub-processes such as fuel-air mixing and air swirl. Finally, some important emissions of the engine are analyzed in current study. It should be mentioned that the NO and CO concentrations are calculated with the models which are based on the chemical kinetics. Results emphasize that the prediction accuracy of the developed model is better than the older model.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Diesel Engine, Multi-zone Combustion Model, Heat Transfer, Emissions.

Prediction of Machining Parameters of Surface Roughness of GFRP Composite by Applying ANN and RSM
by S. Ranganathan, T. Senthilvelan

Vol. 6 n. 5, pp. 1068-1073

Abstract - Glass fibre-reinforced polymer (GFRP) composites are alternative to engineering materials because of economic, light weight, corrosive resistance and superior properties. The experimental research under taken by the scholars is to study the impact of machining parameters on surface roughness of composite material by applying artificial neural network (ANN) and response surface method (RSM). The orthogonal turning operations were carried out on the composite material using tungsten carbide (WC) insert. During machining, the cutting speed (Vc), feed rate (fs) and depth of cut (ap) were varied. Turning experiments were designed based on the statistical three level full factorial experimental design techniques. An artificial neural network and response surface method have been developed, which can predict the surface roughness of the machined workpiece. The experimental results concur well with the results obtained from predictive model.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Composite Material, Turning, Surface Roughness, Artificial Neural Network (ANN), Response Surface Method (RSM).

Characterization of Two Sprays Interacting
by A. Amoresano, C. De Nicola, F. De Domenico

Vol. 6 n. 5, pp. 1074-1081

Abstract - In order to obtain an appreciable effect of extinction of the heat from a heat source (eg a fire) it is necessary that the water flows are high (20- 30 liters per minute) and the droplet diameters are between 20 and 100 microns. To achieve both of these two features the type of nozzle to be used has to be multi hole and supply pressures have to exceed 80 bars. In these conditions there are strong interactions between the individual holes - that generate particular phenomena such as the air entrainment - and the generation of areas where the drops tend to stagnate. To understand the physics of this second phenomenon, the interaction of two sprays is studied in this paper. The article focuses on the region of interaction between the two sprays, which is characterized by using a PDPA system.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Spray Characterization, PDPA Measurements, Two Phase Fluid.

A sensitive methodology for the EGR optimization: a perspective study
by A. Amoresano, V. Niola, A. Quaremba

Vol. 6 n. 5, pp. 1082-1088

Abstract - The policy of reducing emissions in the energy sector is one of the scientific community’s main research topics. There have been significant developments in automotive and business fields, particularly in diesel engines. Nowadays, the method, which is widely used in reducing emissions of a Diesel engine, is the dilution factor called EGR through which it is possible to lower NOx levels. With the reduction of NOx also the performance of a diesel engine (e.g. the stable combustion and engine power) should be evaluated. This paper presents a useful methodology for analysing the change of the dynamic of the entire engine system, which is due to small changes in EGR dilution ratio. The adoption of systems with sophisticated signal processing such as the one presented in this paper, allows easier control of complex systems, such as diesel systems HCCI.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: EGR Optimization, Combustion, NOx Emission.

Numerical Analysis of Anti-Icing and De-Icing Thermal Systems
by F. De Domenico, A. Amoresano, C. De Nicola

Vol. 6 n. 5, pp. 1089-1095

Abstract - An aircraft flying at low-moderate altitudes can experience ice formation on its forward surfaces. The impact with super cooled droplets can generate a water film or beads and rivulets on a solid wall which in turn can freeze and cause the ice accretion. In order to protect the aircraft surfaces, an accurate knowledge of local and total impingement characteristics and afterwards of the ice shapes on a real aircraft component is the first prerequisite in designing a proper ice protection system. The present paper proposes a three-dimensional method to estimate the ice accretion on finite wings from its single section using a two-dimensional method. The method is based on the Lagrangian formulation which considers the gas phase as a continuum and calculates the trajectory of each particle in the flow as a result of convection action of various forces (drag, gravity) agents on the particle itself. Integral methods based on the Prandtl lifting-line theory have been implemented to calculate the effective angle along the wingspan and successively to calculate the thermal power necessary to avoid ice formation and accretion. It is possible to give the wing characteristics as a table of geometric variables or as a CAD. The comparison with experimental data drawn from literature points out a significant potential towards accurate prediction of ice accretion characteristics on real finite wings. Further investigations on up-to-date test cases are scheduled to fully validate the present method.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Ice Accretion, Ice Protection Systems, Thermal Resistances.