Showing papers in "International journal of engineering science and technology in 2011"

Synthesis and applications of nano-structured iron oxides/hydroxides - a review

Abstract: The nano iron oxides have been synthesized by almost all the known wet chemical methods which include precipitation at ambient/elevated temperatures, surfactant mediation, emulsion/micro-emulsion, electro-deposition etc. Iron oxides in nano-scale have exhibited great potential for their applications as catalytic materials, wastewater treatment adsorbents, pigments, flocculants, coatings, gas sensors, ion exchangers, magnetic recording devices, magnetic data storage devices, toners and inks for xerography, magnetic resonance imaging, bioseparation and medicine. Nano sized magnetite Fe3O4, and maghemite γ-Fe2O3 exhibiting excellent magnetic properties find applications for biomedical purposes and as soft ferrites. Iron hydroxides and oxyhydroxides such as ferrihydrite, goethite, akaganeite, lepidocrocite are being evaluated for their applications in water purification for the removal of toxic ions. Hematite, α-Fe2O3 in the nano range has been used to obtain transparent paints. In catalysis both iron oxides and hydroxides find application in numerous synthesis processes. This review outlines the work being carried out on synthesis of iron oxides in nano form and their various applications.

Review on cadmium removal from aqueous solutions

Abstract: Cadmium is known to be toxic for living organism even if it is present in low levels. Generally it is associated with zinc and copper minerals and is produced as a byproduct of these industries. It enters the environment from electroplating, smelting, alloy manufacturing, pigments, plastic, cadmium-nickel batteries, fertilizers, pesticides, mining, pigments and dyes, textile operations and refining industries. Various ways of cadmium removal are: precipitation, ion exchange, solvent extraction and adsorption. The present review specifically describes various types of adsorbents which have been used for removing cadmium from aqueous solutions. General emphasis has been on the utilization of agricultural, industrial wastes and low cost synthetic oxides as adsorbents. In most of the studies batch mode data has been evaluated by determining the kinetic, isothermic and thermodynamic parameters. A number of studies have also addressed the mechanism of adsorption process employing instrumental techniques such as XRD, FTIR, SEM etc. Modeling of column data has also been reported by some researchers. More attention needs to be given for regeneration/reuse/ safe disposal of the loaded adsorbents wherein the data are insufficient. The engineering aspects also need attention for commercial application of various adsorbents. International Journal of Engineering, Science and Technology, Vol. 2, No. 7, 2010, pp. 81-103

Applications of phasor measurement units (PMUs) in electric power system networks incorporated with FACTS controllers

Abstract: This paper presents a critical review on different application of Phasor Measurement Units (PMUs) in electric power system networks incorporated with FACTS controllers for advanced power system monitoring, protection, and control. Also this paper presents the current status of the research and developments in the field of the applications of PMUs in electric power system networks incorporated with FACTS controllers. Authors strongly believe that this survey article will be very much useful to the researchers for finding out the relevant references in the field of the applications of PMUs in electric power system networks incorporated with FACTS controllers.

Enhancement of heat transfer using varying width twisted tape inserts

Abstract: The present work shows the results obtained from experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of varying width twisted tape inserts with air as the working fluid. In order to reduce excessive pressure drops associated with full width twisted tape inserts, with less corresponding reduction in heat transfer coefficients, reduced width twisted tapes of widths ranging from 10 mm to 22 mm, which are lower than the tube inside diameter of 27.5 mm are used. Experiments were carried out for plain tube with/without twisted tape insert at constant wall heat flux and different mass flow rates. The twisted tapes are of three different twist ratios (3, 4 and 5) each with five different widths (26-full width, 22, 18, 14 and 10 mm) respectively. The Reynolds number varied from 6000 to 13500. Both heat transfer coefficient and pressure drop are calculated and the results are compared with those of plain tube. It was found that the enhancement of heat transfer with twisted tape inserts as compared to plain tube varied from 36 to 48% for full width (26mm) and 33 to 39% for reduced width (22 mm) inserts. Correlations are developed for friction factors and Nusselt numbers for a fully developed turbulent swirl flow, which are applicable to full width as well as reduced width twisted tapes, using a modified twist ratio as pitch to width ratio of the tape. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 107-118

Characterization of &#947- and α-Fe 2 O 3 nano powders synthesized by emulsion precipitation-calcination route and rheological behaviour of α-Fe 2 O 3

Abstract: Nano crystals of γ-Fe 2 O 3 (maghemite) were synthesized by emulsion precipitation method using kerosene as oil phase, SPAN- 80 (sorbitane monooleate) as the surfactant and sodium hydroxide as the precipitating agent. The characterization of the samples by FTIR (Fourier transform infra-red) and XRD (X-ray diffraction) techniques confirmed the formation of γ-Fe 2 O 3 (maghemite). Analysis by SEM (scanning electron microscope) and TEM (transmission electron microscope) was carried out to study the morphology and particle size. The as prepared samples contained inverse spinel cubic phase maghemite. Effect of initial iron concentration on crystallite size of maghemite showed that it decreased with the decrease in initial iron concentration. Transformation of γ-Fe 2 O 3 to α-Fe 2 O 3 (hematite) was studied by calcining the precursor in the temperature range of 500 to 850°C. Formation/transformation of phases at different temperatures was confirmed by FTIR and XRD studies. Images, obtained by SEM and TEM showed the morphology and nanocrystal formation of hematite. Room temperature rheological behaviour of the synthesized α-Fe 2 O 3 nano powder has been studied. Keywords : Iron oxide, emulsion, nanocrstals, crystal growth, rheological property International Journal of Engineering, Science and Technology , Vol. 2, No. 8, 2010, pp. 118-126

Optimal placement of distributed generation in distribution networks

Abstract: This paper proposes the application of Particle Swarm Optimization (PSO) technique to find the optimal size and optimum location for the placement of DG in the radial distribution networks for active power compensation by reduction in real power losses and enhancement in voltage profile. In the first segment, the optimal size of DG is calculated at each bus using the exact loss formula and in the second segment the optimal location of DG is found by using the loss sensitivity factor. The analytical expression is based on exact loss formula. The optimal size of DG is calculated at each bus using the exact loss formula and the optimal location of DG is found by using the loss sensitivity factor. The proposed technique is tested on standard 33-bus test system and the obtained results are compared with the exhaustive load flows.

A comparative study on Pb(II), Cd(II), Cu(II), Co(II) adsorption from single and binary aqueous solutions on additive assisted nano-structured goethite

Abstract: Development of low cost adsorbents for mitigation of toxic ions is one of the most important areas of research and development. Iron oxides especially in nano form have the potential for removing cations due to their structural properties. In the present work additive assisted nano structured goethite was synthesized at pH 3.0 and its cation adsorption behaviour was studied for Pb(II), Cd(II), Cu(II) and Co(II) from single and binary aqueous solutions. The contact time data for single cation adsorption followed pseudo second order kinetic model for all the four cations. The isothermic data was fitted to Langmuir and Freundlich models. The experimentally obtained maximum loading capacities were estimated as 109.2, 86.6, 29.15 and 37.25 mg/g of goethite for Pb(II), Co(II), Cd(II) and Cu(II) respectively from single cation containing solutions. Thermodynamic parameters were evaluated for the four metal ions. Adsorption behaviour from binary solutions was studied by keeping the concentration of Pb(II) at saturation concentration (500 mg/L) for its maximum uptake and varying the concentration of other metal ions (one at a time) in the range of 25 to 200 mg/L. The Pb(II) loading capacity increased in the presence of Cd(II) or Co(II) while it decreased in the presence of Cu(II) in the studied range of concentration variation. Maximum Pb(II) uptake was observed from Pb(II)-Cd(II) binary system (222 mg/L) with Pb II) and Cd(II) concentration as 500 and 200 mg/L respectively. An increase in the combined uptake capacities for Pb(II)-Cd(II) and Pb(II)-Co(II) binary systems were observed whereas a decrease was observed for Pb(II)-Cu(II) binary system. The synthesized goethite can be used effectively for cation removal from single/binary cation containing aqueous solutions. Keywords : Nano goethite; TEM, adsorption; cations; binary; kinetics International Journal of Engineering, Science and Technology , Vol. 2, No. 8, 2010, pp. 89-103

Fabrication of iron-cerium mixed oxide: an efficient photocatalyst for dye degradation

Abstract: We report herein the fabrication of nanostructured and mesoporous iron-cerium mixed oxides for photocatalytic application. Phase, electronic structure and other properties of the products were characterized by both low-angle and wide-angle X-ray diffraction, diffuse reflectance spectroscopy, transmission electron microscopy, raman spectroscopy, X-ray photoelectron spectroscopy, and N 2 adsorption-desorption isotherm methods. Analytical results demonstrate that the catalyst is in the nano order and mesoporous in nature. These samples were screened for photocatalytic degradation of phenol, methylene blue (MB) and congo red (CR). About 13 % (phenol) and 93 % (MB) photodegradation were observed where as complete mineralization was obtained in case of CR. The reason for higher catalytic activity of 1:1 (Fe/Ce) sample is ascribed to their higher surface area, surface acidity which determines the active sites of the catalyst and accelerates the photocatalytic reaction. Keywords : Mixed oxide, photocatalyst, photodegradation International Journal of Engineering, Science and Technology , Vol. 2, No. 9, 2010, pp. 53-65

A prepaid meter using mobile communication

Abstract: Energy meters in India have dominantly been electromechanical in nature but are gradually being replaced by more sophisticated and accurate digital and electronic meters. A high percentage of electricity revenue is lost to power theft, incorrect meter reading and billing, and reluctance of consumers towards paying electricity bills on time. Considerable amount of revenue losses can be reduced by using Prepaid Energy Meters. A prepaid energy meter enables power utilities to collect energy bills from the consumers prior to the usage of power by delivering only as much as what has been paid for. This paper suggests a prepaid energy meter behaving like a prepaid mobile phone. The meter contains a prepaid card analogous to mobile SIM card. The prepaid card communicates with the power utility using mobile communication infrastructure. Once the prepaid card is out of balance, the consumer load is disconnected from the utility supply by the contactor. The power utility can recharge the prepaid card remotely through mobile communication based on customer requests. A prior billing is bound to do away with the problems of unpaid bills and human error in meter readings, thereby ensuring justified revenue for the utility. The proposed prepaid meter is implemented in a software model and Matlab has been used for simulation.

A multiple choice decision analysis: an integrated qfd-ahp model for the assessment of customer needs

Abstract: The aim of this work is to propose a new methodological approach to define customer specifications through the employment of an integrated Quality Function Deployment (QFD) – Analytic Hierarchy Process (AHP) model. The model, which is loosely based on QFD, incorporates the AHP approach to delineate and rank the relative importance weight of expressed judgments for customer needs and functional characteristics. The Analytic Hierarchy Process is very useful for this aim because it is a mathematically rigorous, proven process for prioritization and decision-making. By reducing complex decisions to a series of pair-wise comparisons, then synthesizing the results, decision-makers arrive at the best decision with a clear rationale for that decision. The methodology adopted in this work is directed to evaluate as well as rank the definition of the customer’s needs and functional characteristics among several alternatives. The approach has been validated in a real case study concerning the filter in ceramic material production. Keywords : Quality Function Deployment, Analytic Hierarchy Process, Multi Criteria Decision Analysis International Journal of Engineering, Science and Technology , Vol. 2, No. 9, 2010, pp. 25-38

Review of distributed generation planning: objectives, constraints, and algorithms

Abstract: The Distributed Generation (DG) technologies, which include both conventional and non-conventional type of energy sources for generating power, are gaining momentum and play major role in distribution system as an alternative distribution system planning option. The penetration of DGs is potentially beneficial if distributed generation planning (DGP) is optimal i.e. their site and size are selected optimally by optimization of single or multi-objective function under certain operating constraints. Many researchers have presented some rigorous optimization-based methods for DGP. This paper will review the various objectives, different constraints as well as optimization based models using conventional algorithms, intelligent searches and fuzzy set applications in DGP.

An evaluation of utility of Jatropha curcas L. as a source of multiple energy carriers

Abstract: Jatropha curcas L. (JCL) is a popular energy crop in tropical countries. The crop has multiple uses including supply of energy. The major source of energy from JCL the seed oil, which can be used in the raw form or as biodiesel. Biodiesel is a first generation energy carrier. Other products obtained from JCL during its production and processing include wood, fruit shells, seed husks and press-cake. Not much attention has been paid to the energy value of these components. This paper reviews the energy norms of these components and their energy value. Technologies exist to convert these into liquid, gaseous and solid energy carriers. The technologies include anaerobic digestion, pyrolysis, gasification, trans-esterification and combustion. Use of these technologies can optimize the utility of JCL as a source of multiple energy carriers. There is need for integration of the available and distributed data, knowledge and experiences on use of JCL as an energy source into an aggregated discourse. This paper attempts to review the available information on the use of JCL as a source of multiple energy carriers with the objective to provide a complete analysis of the potential energy value of JCL. International Journal of Engineering, Science and Technology, Vol. 2, No. 7, 2010, pp. 115-122

Inhibition ability of probiotic, Lactococcus lactis, against A. hydrophila and study of its immunostimulatory effect in tilapia (Oreochromis niloticus)

Abstract: The present study was designed to investigate the inhibition ability of probiotic, Lactococcus lactis RQ516, against A. hydrophila in vitro and its immunostimulatory effect in tilapia, Oreochromis niloticus as growth promoter. Six tanks were used (T-1 and control treated with and without RQ516, respectively) and three replicates per treatment. The inhibition ability assay in vitro showed that the minimum diameter of the inhibition zone ( P P P P Lactococcus lactis RQ516 was beneficial for tilapia in terms of increasing final weight, DWG and the concentrations of serum protein and globulin and enhancing immune responses. International Journal of Engineering, Science and Technology, Vol. 2, No. 7, 2010, pp. 73-80

A hybrid sequential approach for data clustering using K-Means and particle swarm optimization algorithm

Abstract: Clustering is a widely used technique of finding interesting patterns residing in the dataset that are not obviously known The K-Means algorithm is the most commonly used partitioned clustering algorithm because it can be easily implemented and is the most efficient in terms of the execution time However, due to its sensitiveness to initial partition it can only generate a local optimal solution Particle Swarm Optimization (PSO) technique offers a globalized search methodology but suffers from slow convergence near optimal solution In this paper, we present a new Hybrid Sequential clustering approach, which uses PSO in sequence with K-Means algorithm for data clustering The proposed approach overcomes drawbacks of both algorithms, improves clustering and avoids being trapped in a local optimal solution Experiments on four kinds of data sets have been conducted The obtained results are compared with K-Means, PSO, Hybrid, K-Means+Genetic Algorithm and it has been found that the proposed algorithm generates more accurate, robust and better clustering results International Journal of Engineering, Science and Technology, Vol 2, No 6, 2010, pp 167-176

Bidirectional DC-DC converter fed drive for electric vehicle system

Abstract: Batteries are the primary energy-storage devices in ground vehicles. Now days battery fed electric drives are commonly being used for electric vehicles applications, due to various advantages, such as: nearly zero emission, guaranteed load leveling, good transient operation and energy recovery during braking operation. To fulfill these requirements converters with bidirectional power flow capabilities are required to connect the accumulator (battery) to the dc link of the motor drive system. Battery fed electric vehicles (BFEVs) is required to function in three different modes namely: acceleration mode, normal (steady-state) mode and braking (regenerative) mode. During acceleration and normal modes the power flow is from battery to motor where as during braking or regenerative mode the kinetic energy of the motor is converted into electrical energy and fed back to battery. The DC-DC converter is required to perform mainly two functions: first to match the battery voltage to the motor rated voltage and second to control the power flow under steady-state and transient conditions, so that the drive performance is as per the requirement. In the present work closed loop operation of bi-directional dc-dc converter feeding a dc motor and its energy recovery due to regenerative braking has been demonstrated. The characteristics of battery operated electric vehicle under different drive condition are also presented. The effectiveness of the system is verified through the simulations using Simulink/ MATLAB 7.6.0 (R2008a) package.

Implementation of fuzzy logic control algorithm in embedded microcomputers for dedicated application

Abstract: Fuzzy logic control algorithm solves problems that are difficult to address with traditional control techniques. This paper describes an implementation of fuzzy logic control algorithm using inexpensive hardware as well as how to use fuzzy logic to tackle a specific control problem without any special software tools. As a case study, hardware implementation of fuzzy control algorithm for online temperature control system is demonstrated using 8-bit microcontroller. The hardware implementation followed by software approach has been discussed. Real time result of fuzzy logic temperature control system is also presented.

Rolling bearing fault diagnostics using artificial neural networks based on Laplace wavelet analysis

Abstract: A study is presented to explore the performance of bearing fault diagnosis using three types of artificial neural networks (ANNs), namely, Multilayer Perceptron (MLP) with BP algorithm, Radial Basis Function (RBF) network, and Probabilistic Neural Network (PNN). The time domain vibration signals of a rotating machine with normal and defective bearings are preprocessed using Lapalce wavelet analysis technique for feature extraction. The extracted features are used as inputs to all three ANN classifiers: MLP, RBF, and PNN for four-class: Healthy, outer, inner and roller faults identification. The procedure is illustrated using the experimental vibration data of a rotating machine with different bearing faults. The results show the relative effectiveness of three classifiers in detection of the bearing condition with different learning speeds and success rates.

Recent techniques used in transmission line protection: A review

Abstract: This article presents a survey of the developments in digital relays for protection of transmission lines. For a modern power system, selective high speed clearance of faults on high voltage transmission lines is critical and this survey indicates the efficient and promising implementations for fault detection, classification and fault location in power transmission line protection. The work done in this area favor computerized relays, digital communication technologies and other technical developments, to avoid cascading failures and facilitate safer, secure and reliable power systems. Efforts have been made to include almost all the techniques and philosophies of transmission line protection reported in the literature up to October 2010. The focus of this article is on the most recent techniques, like artificial neural network, fuzzy logic, fuzzy-neuro, fuzzy logicwavelet based and phasor measurement unit-based concepts as well as other conventional methods used in transmission line protection.

Synthesis of &#947–Fe 2 O 3 nanoparticles with crystallographic and magnetic texture

Abstract: Maghemite (γ-Fe 2 O 3 ) nanoparticles are synthesized by chemical co-precipitation technique in AOT-microemulsion with a view to have possible application for biotagging. The investigations by means of X-ray diffraction, isothermal magnetization M (H) and 57 Fe Mossbauer Spectroscopy show that the particles are nonspherical, mostly of rod shape. The inter-particle interaction is so large that even a powder sample of thickness about 40 mg/cm 2 shows preferential orientation of magnetic moments in the plane of the sample. The saturation magnetization is much lower than the expected values for maghemite. Keywords : Maghemite, Magnetic nanoparticles, Magnetic Ordering, Mossbauer spectroscopy International Journal of Engineering, Science and Technology , Vol. 2, No. 8, 2010, pp. 33-39

Wind climate modeling using Weibull and extreme value distribution

Abstract: It is very much important to fit wind speed data into some suitable statistical model for two aspects. One is fatigue failure due to periodic vortex shedding and the other is to estimate the wind energy potential of a particular location. For the fatigue failure due to periodic vortex shedding, it is important to analyse the load cycle. The expected number of stress cycles in the projected working life of a structure is related to the expected number of hours in the critical wind speed range and wind climate modelling is required to know this. The most popular model for this purpose is Weibull distribution. Again, wind energy is proportional to the cube of the wind speed and the same Weibull model is appropriate for cubic wind speed with different parameters. But the problem with Weibull distribution is that it fails to describe the upper tail. The aim of this paper is to determine the technique for finding the wind speed range till which Weibull model is appropriate and also to fit upper wind speed data in a suitable statistical distribution like extreme value distribution of type I (Gumbel). The hourly mean wind speed data of Ahmadabad has been used to validate the procedure.

Location of collinear equilibrium points in the generalised photogravitational elliptic restricted three body problem

Abstract: We have discussed the location of collinear equilibrium points in the generalised photogravitational restricted three body problem. The problem is generalised in the sense that both primaries are oblate spheroid. They are source of radiation as well. We have found the solution for the location of collinear point L1. We found that location of collinear point L1 is affected by eccentricity, oblateness and radiation factor terms. The same method may be applied for location of collinear points L2and L3.

Open innovation and supply chain management in food machinery supply chain: a case study

Abstract: Supply chains continue to growth in complexity, including numerous echelons and numerous players per echelon. Consequently, a company needs to integrate its activities with suppliers and customers, in order to survive. Innovation is a typical example of activity that a company should share with suppliers and customers. In particular, over the last few years, a specific concept of “open innovation” has been paving the way in the innovation management field. This paradigm describes a new approach to internal R&D management, which assumes that firms can and should use external ideas and internal ones, as well as internal and external paths to market, as they look to advance their technology. The aim of this paper is to provide insights toward open innovation practices in a specific supply chain, the food machinery one, moved by the consideration that there is little empirical evidence of open innovation strategies within this context. By means of case studies and semi-structured interviews, we examine a three-echelon supply chain, thus providing a picture of the adoption of open innovation in the food machinery industry. Results show that the actors that more adopt this new paradigm are manufacturer and customer, although all the three actors investigated agreed in defining the benefits derived from innovation and open innovation mechanisms. From this study, theoretical and practical implications can be derived and transferred to the whole food machinery industry. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 244-255

Influence of process parameters on the cup drawing of aluminium 7075 sheet

Abstract: AA7075 is one of the most important structural materials extensively used in automobile and aerospace industries. Extensive research on its formability aspects is required to develop useful components of complex shapes out of this material. One of the ways to measure the formability is to find its deep drawability characteristics. In this study, the significance of three important deep drawing process parameters namely blank temperature, die arc radius and punch velocity on the deep drawing characteristics of aluminium 7075 sheet was determined. The combination of finite element method and Taguchi analysis was used to determine the influence of process parameters. Simulations were carried out as per orthogonal array using DEFORM 2D software. Based on the predicted deformation of deep drawn cup and analysis of variance test (Anova), it was observed that blank temperature has greatest influence on the formability of aluminium material followed by punch velocity and die arc radius. Multiple regression analysis techniques were applied in modelling the behaviour of AA 7075 aluminium alloy under multistep deformation conditions.

Machinability of glass fiber reinforced plastic (GFRP) composite materials

Abstract: This paper deals with the study of machinability of GFRP composite tubes of different fiber orientation angle vary from 300 to 900. Machining studies were carried out on an all geared lathe using three different cutting tools: namely Carbide (K-20), Cubic Boron Nitride (CBN) and Poly-Crystalline Diamond (PCD). Experiments were conducted based on the established Taguchi’s Design of Experiments (DOE) L25 orthogonal array on an all geared lathe. The cutting parameters considered were cutting speed, feed, depth of cut, and work piece (fiber orientation). The performances of the cutting tools were evaluated by measuring surface roughness (Ra) and Cutting force (Fz). A second order mathematical model in terms of cutting parameters was developed using RSM. The results indicate that the developed model is suitable for prediction of surface roughness and Cutting force in machining of GFRP composites.

Antioxidant status of Penaeus monodon fed with Dunaliella salina supplemented diet and resistance against WSSV

Abstract: The present study investigates the protection of shrimp Penaeus monodon against white spot syndrome virus (WSSV) using Dunaliella salina algal cells which contains an antioxidant betacarotene for the shrimp nonspecific immunity. To determine the antioxidant activity, the shrimp were treated in vivo (orally with feed) methods at the concentration of 0.5 %, 1.0 % and 2 % D. salina incorporated with pellet feed, respectively. In the present study, anti-WSSV activity of D. salina incorporated diet by in vivo methods showed strong antioxidant activity and the immunological parameters such as proPO, SOD,catalase were higher in the WSSVinfected shrimp treated with D. salina incorporated diet when compared to control groups. These results strongly indicate that in vivo of D. salina incorporated diet enhances immunity of the shrimp. Based on the present data and the advantages of harvesting D. salina at low price, we believe that oral administration of D. salina live cells along with the pellet feed is a potential prophylactic agent against WSSV infection of shrimp to some extent.

Microstructural characteristics on bead on plate welding of AISI 904 L super austenitic stainless steel using Gas metal arc welding process

Abstract: In the present work, bead-on -plate welds were carried out on AISI 904 L super austenitic stainless steel sheets using Gas Metal Arc Welding (GMAW) process. In this present investigation AISI 904 L solid wire having 1.2 mm diameter was used as an electrode with direct current electrode positive polarity. Argon was employed for shielding purposes. The fusion zone is generally characterized by a few geometrical features namely bead width, bead height and depth of penetration. The shape of the fusion zone depends upon a number of parameters such as gas flow rate, voltage, travel speed and wire feed rate. Taguchi Technique is applied to plan the experiments. The bead profile parameters such as bead width, bead height and depth of penetration are measured. From the experimental results, the gray relational analysis is applied to optimize the input parameters simultaneously considering multiple output variables. In order to understand the microstructural changes occurring in the weld zone is investigated through the optical microscopy. The hardness measurements were taken across the fusion zone. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 189-199

Investigation of blade performance of horizontal axis wind turbine based on blade element momentum theory (BEMT) using NACA airfoils

Abstract: The basic principle of wind turbine converting wind energy into electricity comes from the lift produced by the air flowing through the rotor. The shape of rotor blade plays an important role in determining the overall aerodynamic performance of a horizontal axis wind turbine. In this work, blade is designed for a 5KW horizontal axis wind turbine which is already in market. For designing blade, blade element momentum theory (BEMT) is used and a computer program is developed to automate the complete procedure. Two NACA airfoils are taken for the comparative calculation of elemental power coefficient and other parameters such as chord, thickness and twist distribution. The airfoil taken for designing the blade is same from root to tip. Stresses are maximum at the blade root. In this work, the blade root is thickest portion of the blade and twist is maintained such that the angle of attack will be maximum at every station of the blade. In the designed blade, the elemental power coefficient is maximum in transition segment. The present method is useful for predicting the performance of wind turbine blade.

Optimization of injection pressure for a compression ignition engine with cotton seed oil as an alternate fuel

Abstract: The major problem with the direct use of vegetable oils as fuel into CI engines is their higher viscosity. It interferes the fuel injection and atomization and contributes to incomplete combustion, nozzle clogging, excessive engine deposits, ring sticking, producing thick smoke, etc. The problem of higher viscosity of vegetable oils can be overcome to a greater extent by various techniques, such as heating of fuel lines, trans-esterification, modification of injection system, etc. In the present investigation, short term tests were conducted with the use of untreated cotton seed oil in a single cylinder, four stroke, and direct injection diesel engine. Tests were conducted with cotton seed oil and diesel. To improve the combustion characteristics of cotton seed oil in an unmodified engine, effect of increase in injection pressure was studied. The injection pressure was increased from 180 bar to 240 bar (in steps of 15 bar). The investigation revealed that the optimum pressure for cottonseed oil as 210 bar and comparison of the performance of the engine was studied in terms of brake specific fuel consumption, brake thermal efficiency, indicated thermal efficiency, mechanical efficiency and exhaust emissions. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 142-149

Anisotropy abrasive wear behavior of bagasse fiber reinforced polymer composite

Abstract: In this paper, an experimental study has been conducted to determine the abrasive wear behavior of bagasse fiber reinforced epoxy composite in different directions, namely parallel orientation (PO), anti-parallel orientation (APO) and normal orientation (NO) by using a two body abrasion wear tester. Three different types of abrasives wear behaviour have been observed in the composite in three orientations and follow the following trends: WNO < WAPO < WPO, where WNO, WAPO and WPO are the wear in normal, anti-parallel and parallel directions of fibres orientation, respectively. The fiber bundles present in the composite provide unique directional abrasive wear properties. Wear anisotropy magnitude of the composite is found to be a function of load and abrasive grit size. The worn surfaces were observed by using a SEM after the wear test. It has been found that in PO type samples the abrasion takes place due microploughing, where as in APO and NO type samples micro cutting found to be responsible for the wear process.

A novel calibration algorithm for five-hole pressure probe

Abstract: Five-hole pneumatic pressure probes are used to carry out the steady-state measurements of three components of velocity, inflow angles, static and total pressures simultaneously for a point in a flow field. Various calibration algorithms for five-hole probes are studied in this paper as reported in the literature. Authors have defined non-dimensional pressure coefficients in different ways. Based on certain limitations, a new set of pressure coefficients are proposed in this paper, which overcome the limitations in the literature and gives less computational errors in calculating the flow parameters. In this method, the influence of pressure recorded by central hole ( 5 P ) is considered in defining these coefficients. From 4th order regression analysis, the average values of r2 parameters for all zones are 0.9979 and 0.9910 for a and â respectively, and which are even better than that reported in the all existing methods