ARPN Journal of Engineering and Applied Sciences                         ISSN 1819-6608
 
 
 
ARPN Journal of Engineering and Applied Sciences                February 2009 | Vol.4  No.1
Title:

Simulation of in-cylinder processes in a DI diesel engine with various injection timings

Author (s):

S. M. Jameel Basha, P. Issac Prasad and K. Rajagopal

Abstract:

The gas motion inside the engine cylinder plays a very important role in determining the thermal efficiency of an internal combustion engine. A better understanding of in cylinder gas motion will be helpful in optimizing engine deign parameters. An attempt has been made to study the combustion processes in a compression ignition engine and simulation was done using computational fluid dynamic (CFD) code FLUENT. An Ax symmetric turbulent combustion flow with heat transfer is to be modeled for a flat piston 4-stroke diesel engine. The unsteady compressible conservation equations for mass (Continuity), axial and radial momentum, energy, species concentration equations can express the flow field and combustion in ax symmetric engine cylinder. Turbulent flow modeling and combustion modeling was analyzed in formulating and developing a model for combustion process.

 
 
 
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Title:

Transverse far-field distribution in quantum cascade laser

Author (s):

A. Hamadoua

Abstract:

In this paper, we perform a transverse far-field calculation for a quantum cascade laser treated as a rectangular waveguide. An analytical method for the solution of integral diffraction equation that describes the transverse far -field in a quantum cascade laser is presented. The equations permitting to calculate the full width at half maximum in both directions, parallel and perpendicular to the growth are determined and compared with reported experimental results.

 
 
 
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Title:

Effect of chemical admixture on corrosion resistance of reinforced steel rods in concrete

Author (s):

R. Manoharan, P. Jayabalan and K. Palanisamy

Abstract:

Water reducing admixture is widely used in concretes with less water-cement ratio, to improve some properties like strength and workability. In addition, this admixture has effect on corrosion resistance of embedded re-bars in concrete. In this work, the corrosion rate of mild steel rod, CTD (Cold Twisted Deformed) rod and TMT (Thermo Mechanically Treated) rod were observed by adding water reducing admixture in M25 concrete mix. By varying the percentage of admixture, the study was carried out for a period of 14 months. The corrosion rates were measured at different intervals by conducting electrochemical tests like ACI test, LPR test, and OCP test and by weight loss test (gravimetric method). In most of the time and cases, the corrosion rate was found to be less for 0.5% of water reducing admixture. Corrosion resistance of TMT rod is better than other rods like mild steel and CTD rods.

 
 
 
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Title:

Elastic and mechanical properties of glass specimen by ultrasonic method

Author (s):

A. N. Kannappan,  S. Thirumaran and R. Palani

Abstract:

Ultrasonic velocity and density measurements in Na2CO3 – ZnO – B2O3 and Na2CO3 – PbO – B2O3 composition glasses have been made at a temperature of 303K. These measured values are used to evaluate elastic modulii such as longitudinal, Young’s, bulk and shear, Poisson’s ratio, acoustic impedance, micro hardness, Debye temperature and thermal expansion coefficient. The results of these parameters have been discussed in terms of the structural and physical properties of the prepared glasses.

 
 
 
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Title:

Statistical inferences in market research for sustainable development in conference tourism

Author (s):

Karagiannis Stephanos

Abstract:

The action and the interventions that are based on the research, especially in our days, very often create permanent and viable results, in the environment, in the local society and in the economy. In our proposal the constant question, is the investigation of other forms of tourism, after the decrease of the traditional tourism product. Specifically, for concrete geographic units and regions of our country that face problems of isolation or even those that not have easy access (e.g. islander or mountainous tourist regions), serial or declining demographic base, unfavourable socio-economic structure and low or not developmental records try to attract alternate forms of tourism, e.g.. Conference tourism.

 
 
 
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Title:

Equilibrium and kinetic studies on biosorption of zinc onto gallus domesticus shell powder

Author (s):

G. Kalyani, G. Babu Rao, B. Vijaya Saradhi and Y. Prasanna Kumar

Abstract:

Biosorption is potentially an attractive technology for treatment of wastewater for retaining heavy metals from dilute solutions. Studies carried through the environmental biotechnology have shown that many biosorbents present in the nature have great capacity for removal of heavy metals. The paper presents the results of studies carried out on sorption of zinc ions from aqueous solutions by Gallus Domesticus shell powder as a low-cost sorbent. It was found that crushed Gallus Domesticus shell posse’s relatively high sorption capacity, when comparing with other sorbents that was evaluated as 46.05 mg/g. The biosorption experiments were performed under various conditions such as different initial concentrations, pH, biosorbent concentration and biosorbent particle size. It was found that the equilibrium of the process was reached after 60 min. About 0.1g of Gallus Domesticus shell powder was found to be enough to remove 86.50% of zinc for 20 mg/l of metal ion concentration from 30 ml aqueous solution. The optimum pH value was found to be 6. The pseudo first order and pseudo second order kinetic models were used to describe the kinetic data. The dynamic data fitted with the pseudo second order kinetic model for zinc. The experimental equilibrium data were adjusted by the biosorption isotherms from Langmuir, Freundlich, Redlich & Peterson and Temkin models, and their equilibrium parameters were determined. The best-adjusted model to the experimental equilibrium data for eggshell powder was the Freundlich model followed by Langmuir model.

 
 
 
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Title:

Quantification of runoff, soil loss and silt deposition in agricultural watershed

Author (s):

S. B. Jadhav, S. R. Kalbande and S. D. Vikhe

Abstract:

Watershed development programme has been implemented at Wagarwadi in Aundha Tq. of Hingoli district. The various soil and water conservation measures adopted are nala bunding, gully control structures, cement plug, loose boulder dams etc. The total runoff of 142.4, 206.0 and 193.0 mm received during the year 1997-98, 1998-99 and 1999-2000, respectively. The average sediment concentration of 4.33, 1.41 and 1.06 gm/liter was observed in the year 1997-98, 1998-99 and 1999-2000, respectively. It is also seen that 1622.575, 1327.58 and 942.56 tones of soil is found to be deposited at different structures.  Due to adoption of soil and water conservation programme, the silt has been deposited in the watershed itself rather than to transport from the watershed.

 
 
 
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Title:

Genetic algorithm applied to fractal image compression

Author (s):

Y. Chakrapani and K. Soundera Rajan

Abstract:

In this paper the technique of Genetic Algorithm (GA) is applied for Fractal Image Compression (FIC). With the help of this evolutionary algorithm effort is made to reduce the search complexity of matching between range block and domain block. One of the image compression techniques in the spatial domain is Fractal Image Compression but the main drawback of FIC is that it involves more computational time due to global search. In order to improve the computational time and also the acceptable quality of the decoded image, Genetic algorithm is proposed. Experimental results show that the Genetic Algorithm is a better method than the traditional exhaustive search method.

 
 
 
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Title:

Innovative thinning and gradient algorithm for binary and grey tone images using first in first out linear data structure

Author (s):

R. M. Noorullah and A. Damodaram

Abstract:

Homotopic Thinning algorithms have long been investigated in pattern recognition and image analysis. However, they are order dependent in the sense that the output depends upon the order used for processing the image pixels as well as the order in which homotopic structuring elements are applied for algorithms based on sequential homotopic thinning. In the present study an algorithm will be proposed to tackle the disadvantage by introducing an effective notion for order independent homotopic thinning by using First in First out Linear Data Structure. A critical study will be made for analyzing the algorithms by considering appropriate anchor points for skeletonization and by homotopic marking.

 
 
 
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Title:

Resistance of fly ash based geopolymer mortars in sulfuric acid

Author (s):

Suresh Thokchom, Partha Ghosh and Somnath Ghosh

Abstract:

The present paper reports the experimental results of a study conducted to assess the resistance of fly ash based geopolymer mortar specimens in sulfuric acid. The program consisted immersion of geopolymer mortar samples having percentage Na2O ranging from 5-8% of fly ash in a 10% sulfuric acid solution up to a period of 18 weeks and evaluation of its resistance in terms of visual appearance, residual alkalinity, changes in weight and compressive strength at regular intervals. Visual inspection of geopolymer mortar samples did not reveal any recognizable change in colour and remained structurally intact though the exposed surface turned slightly softer. Through Optical microscope, corroded surface could be seen which increased with time of exposure. After exposure in the acid solution for 18 weeks, the geopolymer samples almost lost its alkalinity and showed very low weight loss in the range from 0.41% to 1.23% of initial weight. Loss of weight was found higher for specimen with higher percent of Na2O. Compressive strength loss at the end of test was 52% for specimen with 5% Na2O and 28% for specimens with 8% Na2O. Results obtained in the present study indicate that geopolymers are highly resistant to sulfuric acid.

 
 
 
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Title:

Modeling of six-pulse rectifier operating under supply unbalanced conditions

Author (s):

Hussein A. Kazem, B. Zahawi and D. Giaouris

Abstract:

Modeling of the six-pulse rectifier bridge circuit, operating under practical operating conditions, when connected to an unbalanced three-phase supply is presented in this paper. The time domain model takes full account of system losses and supply impedance on circuit current and voltage waveforms, allowing for DC current ripple and the changing states of conduction of the converter devices. The analysis is valid for all types of loads and converter conduction modes, including mode 3 overlap when the angle of overlap extends beyond 60° and the number of conducting devices alternate between 3 and 4. The proposed results are very close to the simulation results.

 
 
 
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Title:

Novel space vector based generalized discontinuous PWM algorithm for induction motor drives

Author (s):

K. Sri Gowri, T. Brahmananda Reddy and Ch. Sai Babu

Abstract:

This paper presents a novel space-vector based Generalized Discontinuous pulse width modulation (GDPWM) algorithm without angle estimation based on the concept of imaginary switching times. The conventional space vector pulse width modulation (CSVPWM) method with equal division of zero state vectors V0 and V7 is modified. A constant-variable μ and modulation phase angle δ ranging from 0 to 1 are used to generate infinite number of modulating waveforms. Also, the classical triangle comparison approach is replaced by space vector approach. To avoid the complex coordinate transformations, trigonometric calculations and sector identification involved in CSVPWM, the concept of imaginary switching times is utilized. The imaginary switching times proportional to the reference phase voltages are used to calculate the actual switching times for reduced complexity and memory required. The proposed PWM technique results in reduced current ripple over the CSVPWM at high modulation indices and low switching losses at all modulation indices. To validate the proposed method, simulation is carried out on V/f controlled induction motor and the no-load current waveforms at different modulation indices and frequencies are presented and %THDs is compared.

 
 
 
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Title:

Evaluation of cement Nala plug

Author (s):

S. B. Jadhav, S. R. Kalbande and S. D. Vikhe

Abstract:

A field study to evaluate the cement nala plug in Wagarwadi watershed of Hingoli district was carried out during 1998-99. Water storage characteristics in the cement nala plug was studied by monitoring the depth of water storage in cement plug and length of water spread. The losses from surface water storage in the form of evaporation and seepage/percolation were estimated. The effect of seepage on ground water recharge was studied by monitoring water levels in the observation wells. Utilization of stored water in the cement nala plug was observed. The full water storage of cement nala plug was found to be 1725.91m, with the maximum length and width of spread, 11.3m and 14.0m, respectively with maximum impounding of water as 3.0m. The maximum evaporation loss and seepage loss from the cement nala plug was found to be 257.2 m3 and 1634 m3, respectively. The impounded water in cement nala plug resulted in the increase in water levels in the observation wells of the influencing area. Due to silting, the storage capacity of the cement nala plug was reduced by 2.16 percent in 5 years its construction with silt retention rate of 24.124 tonnes/year.

 
 
 
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Title:

Isolation of atranorin, bergenin and goniothalamin from Hopea sangal

Author (s):

Jamal A. Nasser, W. A. Yaacob, Laily B. Din, Bohari M. Yamin and Jalifah Latip

Abstract:

A phytochemical investigation was conducted on Hopea sangal (Dipterocarpaceae). Three compounds whose names were atranorin, bergenin and goniothalamin were isolated from the ethyl acetate extract of the stem bark of the plant. The structures of these compounds were determined by X-ray and NMR. Studies with the latter involve 1H, 13C and APT spectral data.

 
 
 
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