ARPN Journal of Engineering and Applied Sciences                         ISSN 1819-6608
   
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ARPN Journal of Engineering and Applied Sciences                 March 2010 | Vol. 5  No. 3
   
Title:

Investigations on self-compacted self-curing concrete using limestone powder and clinkers

Author (s):

C. Selvamony, M. S. Ravikumar, S. U. Kannan and S. Basil Gnanappa

Abstract:

Self- Compacting concrete is a type of concrete that gets compacted under its self-weight. Itís commonly abbreviated as SCC and defined as the concrete which can placed and compacted into every corner of a formwork; purely means of itís self-weight by eliminating the need of either external energy input from vibrators or any type of compacting effort. Self compactability and stability are susceptible to ternary effects of chemical and mineral admixture type and their content. In this study, the effect of replacing the cement, coarse aggregate and fine aggregate by limestone powder (LP) with silica fume, quarry dust  and clinkers respectively and their  combinations of various proportions on the properties of SCC has been compared. Fresh properties, flexural and compressive strengths and water absorption properties of Concrete were determined. The use of SF in Concrete significantly increased the dosage of superplasticiser (SP). At the same constant SP dosage (0∑8%) and mineral additives content (30%), LP can better improve the workability than that of control and fine aggregate mixtures by (5 % to 45 %). However, the results of this study suggest that certain QD, SF and LP combinations can improve the workability of SCCs, more than QD, SF and LP alone. LP can have a positive influence on the mechanical performance at early strength development while SF improved aggregate-matrix bond resulting from the formation of a less porous transition zone in Concrete. SF can better reducing effect on total water absorption while QD and LP will not have the same effect, at 28 days.

 
 
 
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Title:

Localization of faults on power transmission lines using traveling wave theory (TWT)

Author (s):

B. Ravindhranath Reddy, M. Vijay Kumar, M. Surya Kalavathi and P. Rajini Kumar

Abstract:

Transmission lines are designed to transfer electric power from source locations to distribution networks. However, their lengths are exposed to various faults. Protective relay and fault recorder systems, based on fundamental power frequency signals, are installed to isolate the faulty line and provide the fault position. However, the error is high especially in transmission lines. This work investigates the problem of fault localization using travelling wave current signals obtained at a single-end of a transmission line and/or at multi-ends of a transmission network.

 
 
 
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Title:

Some investigations in friction drilling AA6351 using high speed steel tools

Author (s):

P. V. Gopal Krishna, K. Kishore and V. V. Satyanarayana

Abstract:

Friction drilling is a non traditional hole making process in which a conical rotating tool is applied to penetrate into workpiece and create the hole in a single step, without generating chips. The process relies on the heat generated due to the frictional force between tool and workpiece, to soften, penetrate and deform the work material into a bushing shape. The mechanical aspects of friction drilling are investigated in this paper. Aluminum (AA6351) is taken as work material and friction drilling is carried out by high speed steel conical tool. Mathematical models are developed in this work for axial thrust and torque.  Proper experimental layout is designed and Taguchi Method is applied to evaluate the performance of high speed steel friction drill on AA6351 work piece of thickness 1mm.

 
 
 
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Title:

Effect of mixture constituents on the laminar burning velocity of LPG-Co2-air mixtures

Author (s):

Ajay Tripathi, H. Chandra and M. Agrawal

Abstract:

One of the most attractive applications of Liquefied petroleum gas (LPG) is its use in IC engines, particularly for automotive applications, as it is known to be a clean source of energy. Even though it is already being used in IC engines, the fundamental combustion properties such as laminar burning velocities, which is a physicochemical property of a fuel, is still not very well established, which can act as a basic input for engine modeling. The present work utilizes a few standard methods of flame speed measurement known from the literature to obtain the flame speed of LPG-air and LPG-air-diluent mixtures as a function of air-fuel ratio and diluent concentration. Variation of burning velocity obtained by two different experimental techniques, that is, orifice burner and cylindrical tube method for a mixture of LPG-air and diluent mixtures at different air fuel ratios is quantified. CO2 is selected as a diluent to account for the presence of exhaust gases in the fresh charge as a consequence of exhaust gas recirculation. It was found that there is effect on burning velocity with the variation of  effects of diluents on the burning velocities have been found to cause performance problems for combustion appliances using these types of fuel gases.

 
 
 
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Title:

Classification and identification of Telugu handwritten characters extracted from palm leaves using decision tree approach

Author (s):

Panyam Narahari Sastry, Ramakrishnan Krishnan and Bhagavatula Venkata Sanker Ram

Abstract:

Research in character recognition is very popular for various application potentials in banks, post offices, defense organizations, reading aid for the blind, library automation, language processing and multi-media design. Even though Epigraphical work dealing with stone inscriptions have been analyzed, these have been done largely manually and also on 2D traces. A large collection of these are available in the classical Indian languages like Sanskrit, Tamil, Pali etc as well as in more modern languages like Telugu. These characters on the palm leaf have the additional properties like depth, an added feature which can be gainfully exploited in character recognition. In this paper, we explore how these 3D features can be extracted and how they can be used in the recognition and classification process. This paper describes a system to identify and classify Telugu (a south Indian language) characters extracted from the palm leaves, using Decision Tree approach. The decision tree is developed using SEE5 algorithm, which is an improvement from the predecessor ID3 and C4.5 algorithm. The identification accuracy obtained is 93.10% using this method.

 
 
 
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Title:

Monte Carlo simulation for radiation transport: collision density in a 1-D slab

Author (s):

Z. U. Koreshi and S. Siddiq

Abstract:

Monte Carlo (MC) simulation has been abundantly used for simulation of radiation transport (thermal, neutron, charged-particle etc) in matter. In thermal radiation, for example, surface radiosities and subsequent heat fluxes have been accurately determined in configurations which are difficult for deterministic formulations. In this paper, we consider estimation of the collision density in a 1-D slab and compare with the exact solution. The accuracy of the simulation results is discussed and a Poisson distribution is shown for the events in a random walk. The purpose of this paper is to demonstrate the underlying simulation process for a simple problem.

 
 
 
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Title:

Component model-Based condition monitoring of a gas turbine

Author (s):

E. A. Ogbonnaya, K. T. Johnson, H. U. Ugwu and C. U. Orji

Abstract:

In recent years, the requirements for reliability of machines that perform different technological processes and their faults diagnoses have become much stricter on most plants. The individual component models are used to generate the source or cause of fault in the engines. The failure of these components poses a great problem to the equipment manufacturers and owners. A step to the reduction of the faults led to the execution of this work using gas turbine engines as case studies. Component parametric readings collected from a gas turbine engine on industrial duty for power generation were used to enunciate steps to solve the problem by simulating likely deterioration in its component data. A computer program code in Visual Basic was used to actualize the simulation. The  results obtained show that early detection of faults could help to avoid catastrophic downtime. Also the research revealed that the pressure drop across turbine should not exceed 11.4 bar for optimum performance.

 
 
 
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Title:

Explicit dynamic simulation of drop weight low velocity impact on carbon fibrous composite panels

Author (s):

Umar Farooq and Karl Gregory

Abstract:

Finite element computational model was developed to simulate impact behaviour and predict the failure response of carbon fibrous composite panels subjected to low velocity drop-weight impact on the partitioned area where an impactor of flat-nosed tip hits the target. Critical damage regions under impactorsí tips are very complicated phenomenon to study since internal load re-distributes after impact and damage accumulates in through-the-thickness plies. Transformation of mathematical formulations into numerical model and writing modular code also need extensive efforts and time. However, efficient way of solving the problems using commercial software generated simulations. For this work, commercially available software ABAQUSTM was selected, which incorporates shell elements and stacks of plies. The user Table option of the software provides an extended amount of input data without having to re-link the code that could be utilised for various load cases. Model developing and simulation techniques associated with the software usage are presented herein. The developed models are capable to simulate impact phenomena of various drop weights for parametric studies. The methodology applied consists of computing in-plane stresses from the model and using Trapezium rule to calculate transverse shear stresses from the standard equilibrium equations. The method is simple and efficient to predict equivalent 3-D transverse shear stresses from a 2-D model. These predicted and calculated stresses were used in failure theories to predict possible failure modes.  Some of the results from failure threshold loads were selected and included in the form of Tables, contour plots and graphs.

 
 
 
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Title:

Process monitoring and control of machining operations

Author (s):

Uche R and Ebieto C. E.

Abstract:

This paper presents process monitoring and control of machining operations. In this work, a cutting dynamometer mounted on the machine was used to measure the cutting force, cutting speed and the power consumed in the operation. The tool life was also calculated using the Taylorís equation. It was shown that when the cutting tool lifetime elapse, the tool no long give a good cut which imperatively indicates a deteriorating condition of tool life and possible failure.

 
 
 
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Title:

Rapid chloride permeability test for durability studies on glass fibre reinforced concrete

Author (s):

Chandramouli K., Srinivasa Rao P., Seshadri Sekhar T., Pannirselvam N. and Sravana P.

Abstract:

Corrosion of reinforcing steel due to chloride ingress is one of the most common environmental attacks that lead to the deterioration of concrete structures. Corrosion related damage to concrete structures is a major problem. This durability problem has received widespread attention in recent years because of its frequent occurrence and the associated high cost of repairs. Chlorides penetrate crack-free concrete by a variety of mechanisms: capillary absorption, hydrostatic pressure, diffusion, and evaporative transport. Of these, diffusion is predominant. Diffusion occurs when the concentration of chloride on the outside of the concrete member is greater than on the inside. This results in chloride ions moving through the concrete to the level of the rebar. When this occurs in combination with wetting and drying cycles and in the presence of oxygen, conditions are right for reinforcement corrosion. The rate of chloride ion ingress into concrete is primarily dependent on the internal pore structure. The pore structure in turn depends on other factors such as the mix design, degree of hydration, curing conditions, use of supplementary cementitious materials, and construction practices. Therefore, wherever there is a potential risk of chloride-induced corrosion, the concrete should be evaluated for chloride permeability. Researchers all over the world are attempting to develop high performance concretes by using fibres and other admixtures in concrete upto certain proportions. In the view of the global sustainable developments, it is imperative that fibres like glass, carbon, aramid and polypropylene fibers provide improvements in tensile strength. Research in GFRC (Glass fibre reinforced concrete) resulted in the development of an alkali resistance fibre (AR Glass fibres High Dispersion) that provided improved long term durability. In the present experimental investigation cylinders of 100mm x 150mm of M20 grade concrete were cast with varying percentage of addition of 0.03%, 0.06% and 0.1% of glass fibre. The rapid chloride permeability tests were conducted for a period of 90, 180, 365 and 720 days. The test results show that the addition of glass fibres exhibit better performance.

 
 
 
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Title:

Stress-strain behavior of Nano/micro thin film materials

Author (s):

Swaminadham Midturi

Abstract:

Nano/micro size thin films are being developed at present for various applications as stretchable electronic displays, flexible and foldable solar panels, body conformable smart electronic textiles and fabrics, and other embedded sensor-actuator surfaces. This paper describes the results from an experimental investigation of elastic-plastic deformation behavior of nano/micro thick conducting metal such as gold (Au) on a highly compliant, biocompatible polymer such as polydimethylsiloxane (PDMS). Two layer laminates were fabricated with various nano Au film on micron scale PDMS substrate and tested using a micro-tensile tester. Also, in-situ scanning electron microscope (SEM) tests captured the digital images of Au film under static load to explain the changes in grain structure of the gold film.  Stress-strain data for the gold film under large deformation was extracted using a mechanics of material based model, and changes in stiffness values of the Au film were determined. The experimental results validated the Hall-Petch law indicating that the material strength properties have inverse relationship with grain size. Results indicated that the metallic Au films sustained large deformation without rupture and SEM studies indicated that at higher strain levels, grains in the Au film experienced intra-granular fractures.

 
 
 
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Title:

Artificial neural network model for performance evaluation of RC rectangular beams with externally bonded glass fibre reinforced polymer reinforcement

Author (s):

N. Pannirselvam, V. Nagaradjane, K. Chandramouli and M. Ravindrakrishna

Abstract:

The effect of glass fibre reinforced polymer laminates on the performance of reinforced concrete rectangular beams having different internal steel reinforcement ratios was investigated. The parameters of investigation included yield load, ultimate load, yield deflection, ultimate deflection, maximum crack width, deflection ductility and energy ductility. Artificial Neural Network model was generated to predict the performance characteristics taking percentage of steel reinforcement, thickness of glass fibre reinforced polymer and the type of fibre used in glass fibre reinforced polymer as parameters.

 
 
 
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