Volume 2, Issue 7, October 2011

Second Law Analysis of Parallel Plate Ducts with Span Wise Periodic Triangular Corrugations at one Wall

Alireza Falahat

Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– In this study, entropy generation for hydro dynamically and thermally developing laminar flow in a parallel plate ducts with span wise periodic triangular corrugations at one wall at constant heat flux is investigated. Entropy generation is obtained for various aspect ratio (α), various corrugation angle (2Ф), various number of corrugation (n) and various Reynolds number. It is found that with the increasing aspect ratio (α) and various number of corrugation (n) values and decreasing corrugation angle (2Ф), total entropy generation decreases , with increasing aspect ratio (α) and corrugation angle (2Ф)values and decreasing number of corrugation (n), pumping power decreases.

Keywords—: Second Law, Corrugation Duct, Laminar Flow and Aspect Ratio

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Resource Constrained Project Scheduling Using Mean Field Annealing Neural Networks

Mohammad Jaberi

Department of Computers, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– A Potts mean field feedback artificial neural network algorithm is developed and explored for the resource constrained project scheduling problem. A convenient encoding of inequality constraints is achieved by means of multilinear penalty function. An approximate energy minimum is obtained by iterating a set of Potts means field equation, is combination with annealing. Priority rule-based heuristics are the most widely used scheduling methods though their performance depends on the characteristics of the projects. To overcome this deficiency, a Potts mean field feedback artificial neural network is designed and integrated into the scheduling scheme so as to automatically select the suitable activity for each stage of project scheduling. Testing on Paterson’s classic test problems and comparison with other exact method how that the proposed Potts mean field annealing neural network based heuristic is able to improve the performance of project scheduling.

Keywords—Neural Network, Mean Field Theory, Potts Mean Field Theory, Resource-constrained Project Scheduling and Priority Rule-Based Heuristic

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Field-Bus Technology in Modern Control

Sadegh Vosough and Amir Vosough

Department of Electronics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran
Department of mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– In this paper about the important concept of fieldbus and its application has been discussed. The fieldbus technology promises to improve quality, reduce costs and boost efficiency. These promises made by the fieldbus technology are derived partly from the fact that information which a field device is required to transmit or receive can be transmitted digitally. This is a great deal more accurate than transmitting using analogue methods which were used previously. Each field device is also a ‘smart’ device and can carry out its own control, maintenance and diagnostic functions. As a result it can report if there is a failure of the device or manual calibration is required, this increases the efficiency of the system and reduces the amount of maintenance required.

Keywords—Fieldbus, Feathers, Application and Architecture

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Study of Heat Affected Zone (HAZ) in Thermit Welding Process

Ali. Moarrefzadeh

Department of Mechanical Engineering, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– The thermal effect of Thermit welding that specially depends on the electrical arc and temperature field of it in workpiece, is the main key of analysis and optimization of this process, from which the main goal of this paper has been defined. Numerical simulation of welding process in SIMPELC method and by ANSYS software for gaining the temperature field of copper, the effect of parameter variation on temperature field and process optimization for different cases of Thermit are done. The influence of the welding parameter for each mode on the dimensions and shape of the welds and on their ferrite contents is investigated. Despite these simplifications, the model can be used to analyze the thermal conditions during thermit welding with sufficient accuracy. The predicted temperature history, weld deposit, and HAZ profiles were in good agreement with the experimental measurements in laboratory welds. It is found that the weld gap is the most influential welding parameter for rail thermit welding. A wider-gap weld appears to be less sensitive to chance variations in the other welding parameters, and therefore fairly consistent thermal conditions can be obtained.

Keywords—Numerical Simulation, Thermit, FSI, SIMPLEC, Temperature Field and Copper

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The Effect of the Number of Control Points on the Adjusted Satellite Images

Dr. Nagi Zomrawi Mohammed yousif and Abuelhassan Ali Idriss Abdalla

Department of Surveying Engineering, Sudan University of Science and Technology, Sudan

Abstract– Traditional survey methods become tedious and time consuming and hens very cost with large scale mapping surveys. In recent years remote sensing imagery was adopted to reduce the cost and facilitate the survey works. These im-ages require some control points to match with the ground coordinates. This research work is oriented to study the effect of the number of control points on the adjusted satellite im-age. Quick bird image was tested utilizing number of control points. These points were selected on the image first and then observed on the ground using GPS receiver. Some control points was used to adjust the image, where the others were used as check points. Satellite image was repeatedly adjusted and then accuracy was estimated. The effect of the number of control points on the adjusted image was examined by in-creasing the number of control points in georefrencing model and estimating the accuracy in each case. Three georefrencing models were taken into account in this research .These models were first order polynomial, affine and projective model. First order polynomial and affine models require at least 3 control points to adjust a satellite image, where, 4 control points are required when using projective model. Results showed that the accuracy of the adjusted satellite image was improved with increasing the number of control points. And the projective model yield better accuracy using four control points compared with other tested models. Moreover, six control points were sufficiently enough to adjusted satellite image using first order polynomial model. Also results showed that affine model always provides lower accuracy compared with other tested models.

Keywords—GPS, GCPs, RMSE, Georeferancing, Polynomial, Affine and Projective Transformations Models

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Renewable Generation Expansion Planning Based on Power Purchasing Agreement

Mohammad Sadegh Javadi, Rahmat Azami, Amin Javadinasab and Ghasem Hemmatipoor

Department of Electrical Engineering, Shoushtar Branch, Islamic Azad University, Shoushtar, Iran

Abstract– An incentive based program presents in this paper in order to motive the resource expansion planner in a restructured power system. Power Purchasing Agreements (PPAs) are the recent contracts between Generation Companies (GENCOs) and Independent System Operator (ISO) which is right-of way of this paper. After restructuring in power system, lack of motivations for Independent Power Producers (IPPs) to partnership in power generation and long term maintaining energy have affect the long horizon expansion planning. In this area, long term contracts can help the market entities to hedging their risks in satisfying the future demands and ensuring the return of their investment cost. From an IPP point of view, clarifying the rate of return of investment has an important role in his financial decision making. In competitive power market, each GENCO would offer in the market and some of them could exercise market power in power market. One of the proposed ways to controlling the market power is PPA. The aforementioned PPAs are also guarantied the renewable resource planning which need high capital investment. In this paper, the framework of this PPA is proposed and some technical aspects of renewable PPAS are also presented.

Keywords—Renewable Generation Expansion Planning, Power Purchasing Agreement and Independent System Operator

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Design and Manufacture of a Micro Zero Head Turbine for Power Generation

Ali Arslan, Rizwan Khalid, Zohaib Hassan and Irfan A. Manarvi

Department of Mechanical Engineering, HITEC University Taxila, Pakistan

Abstract– A zero head water turbine has been used as a source of power generation where construction of a dam for the head is not required. It works on natural flow of water to generate a specific power output. The power is however limited by flow of water which is sufficient to keep generate a suitable number of revolutions per minutes for the blades. Present research was aimed to design and manufacture a micro zero head turbine which could produce sufficient power to light a couple of energy saver bulbs upto a wattage of 50 to 60 that can suffice the lighting requirements of far flung villagers and dwellers having access to natural streams of water but no electricity supply. It resulted in design and fabrication of one such turbine which was able to generate a power of approximately 50 watts at a free stream velocity of 1.2 meter/second. Findings of this research were quite in harmony with theoretical results which may be used for increasing the size of micro turbine along with a proportionate rise in generated power.

Keywords—Power Generation, Design, Turbine and Results

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Finite-Element Simulation of dimensional limitation of Electro Chemical Machining (ECM) Process

Ali. Moarrefzadeh

Department of Mechanical Engineering, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– Electrochemical Machining (ECM) has established itself as one of the major alternatives to conventional methods of machining difficult - to - cut materials of and/or generating complex contours, without inducing residual stress and tool wear. The need for complex and accurate three dimensional (3-D) micro components is increasing rapidly for many industrial and consumer products. Electrochemical machining process (ECM) has the potential of generating desired crack-free and stress-free surfaces of micro components. This paper reports a study of pulse electrochemical micromachining (PECMM) using ultra short (nanoseconds) pulses for generating complex 3-D microstructures of high accuracy. A mathematical model of the micro shaping process with taking into consideration unsteady phenomena in electrical double layer has been developed. The software for computer simulation of PECMM has been developed and the effects of machining parameters on anodic localization and final shape of machined surface are presented.

Keywords—Finite-Element, ECM, Dimensional, Machining, Temperature Field and Cell

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Entropy Generation Analysis of EG-Al2O3 Nanofluid in Helical Tube and Laminar Flow

Alireza Falahat

Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– In this paper, effects of adding nanoparticle on the entropy generation of EG–Al2O3 nanofluid flows through a helical tube under uniform wall heat flux condition in laminar regime investigated analytically. It is found that adding nanoparticles improves the thermal performance of EG -Al2O3 flow with Re numbers less than 3000. The entropy generation by adding nanoparticles in constant δ and different δ investigated. It is found that with the increasing δ values, total entropy generation decreases at fixed volume concentration. Moreover optimum conditions (based on the entropy generation sense) for laminar nanofluid flows are obtained.

Keywords—Helical Tube, Nanofluid, Entropy Generation and Laminar Flow

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Study of Thermal Optimization in Power Plant

Amir vosough and Sadeghvosough

Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– In this paper about the optimization methods like exergy analyses, Pinch analyses, Combined Pinch and Exergy analysis and Life Cycle Cost Optimization Process have been discussed. The Combined Pinch and Exergy Analysis (CPEA) first consider the representation of the hot and cold Composite Curves of the Rankine cycle and define the energy and Exergy requirements. The basic assumption of the minimum approach temperature difference required for the Pinch Analysis is represented as a distinct Exergy loss that increases the fuel requirement for power generation. The exergy composite curves put the focus on the opportunities for fuel conservation in the cycle.

Keywords—Optimization Methods, Exergy Analysis, Pinch Analysis and Life Cycle Optimization

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Optimal Distributed Generation Expansion Planning Based on Techno-Economical Analysis

Mohammad Sadegh Javadi and Amir Farajifard

Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Fars, Iran
Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

Abstract– Short installation and maintenance period of Distributed Generation (DG) units make them an effective choice for Generation Expansion Planning (GEP) studies in modern power systems. Finding optimal technology and place of DG units should be done in an economical plan that guarantees the investment benefits of investors. In this paper optimal DG expansion decision has been made based on annual load pattern of system and load duration curve. Also an economical evaluation has been presented on expansion choices using sensitivity analysis and value of investment. Presented approach considers both concerns of Independent System Operator (ISO) and Generation Companies (GenCos). A short-term Security Constraint Unit Commitment (SCUC) for each scenario has been considered from ISO's point of view and in the other hand, a long-term economical study in returning the investment capital has been evaluated by each GenCo as a decision makers. The proposed algorithm is applied to IEEE-24 Bus test system. The simulation results show that the presented method is both satisfactory and consistent with expectation.

Keywords—Distributed Generation, Load Duration Curve, Sensitivity Analysis and Decision Making

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Wave Energy

Amir Vosough

Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran

Abstract– Wave power is the transport of energy by ocean surface waves, and the capture of that energy to do useful work – for example, electricity generation, water desalination, or the pumping of water (into reservoirs). Machinery able to exploit wave power is generally known as a wave energy converter (WEC). Wave power is distinct from the diurnal flux of tidal power and the steady gyre of ocean currents. In this paper about the different parts of wave power like physical concept, wave power formula, wave energy, deep power characteristic and opportunities, modern technologies and its challenges and different kind of wave energy extractors have been discussed.

Keywords—WEC, Flux, Wave Power and Challenges

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Connection Oriented Bandwidth Aggregation System

Ehsan Elahi and Amir Qayyum

University of Sargodha, Sargodha, Pakistan
M. A. Jinnah University, Islamabad, Pakistan

Abstract– The abundance of handheld devices with the support of multiple interfaces makes it a common requirement of users to have access to multiple access networks simultaneously in order to obtain increased performance. Aggregating bandwidth of two or more Internet connections makes Internet applications to use the total available bandwidth in order to increase the goodput and reliability with link redundancy. In this paper, a Bandwidth Aggregation System (BAS) along with its implementation is discussed. Moreover a queuing theory based analytical model to derive the performance for aggregating bandwidth using multiple available interfaces for TCP connections is presented. Next, that model has been used to derive an expression for average data transmission rate when BAS is being used. In the end the performance of the model is validated by simulating the BAS and comparing the model predicted results with the experimental results. The comparison shows excellent agreement.

Keywords—Bandwidth Aggregation, Queuing Theory and Performance Modeling

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