Open Access Published by De Gruyter Open Access

Volume 3 Issue 3

September 2013

Issue of Open Engineering

Contents
Journal Overview

Open Access July 28, 2013

Analytical engineering models of high speed normal impact by hard projectiles on metal shields

Gabi Ben-Dor, Anatoly Dubinsky, Tov Elperin

Page range: 349-373

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Abstract

In this review we consider mainly relatively simple engineering models which can be physically substantiated although usually their justification requires a large number of assumptions. These models are characterized by the following features in the case of normal impact: either they determine the relations between the ”integral characteristics” of penetration (depth of penetration, ballistic limit velocity) in the explicit form (in algebraic form or including quadratures) or they describe local interactions between the shield and the penetrator in the points of the penetrator-shield contact surface that yield such integral characteristics. In this overview we present more or less comprehensively all widely used and also not well known analytical models which have been suggested for describing high-speed penetration into metal shields. This survey is characterized by the following distinguishing features: (i) includes an unprecedented large number of models; (ii) presents models suggested during recent years; (iii) analyzes models which have been originally published in Russian and are not well known in the West.

Open Access July 28, 2013

A review of thrust-vectoring in support of a V/STOL non-moving mechanical propulsion system

José Páscoa, Antonio Dumas, Michele Trancossi, Paul Stewart, Dean Vucinic

Page range: 374-388

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Abstract

The advantages associated to Vertical Short-Take-Off and Landing (V/STOL) have been demonstrated since the early days of aviation, with the initial technolology being based on airships and later on helicopters and planes. Its operational advantages are enormous, being it in the field of military, humanitarian and rescue operations, or even in general aviation. Helicopters have limits in their maximum horizontal speed and classic V/STOL airplanes have problems associated with their large weight, due to the implementation of moving elements, when based on tilting rotors or turbojet vector mechanical oriented nozzles. A new alternative is proposed within the European Union Project ACHEON (Aerial Coanda High Efficiency Orienting-jet Nozzle). The project introduces a novel scheme to orient the jet that is free of moving elements. This is based on a Coanda effect nozzle supported in two fluid streams, also incorporating boundary layer plasma actuators to achieve larger deflection angles. Herein we introduce a state-of-the-art review of the concepts that have been proposed in the framework of jet orienting propulsion systems. This review allows to demonstrate the advantages of the new concept in comparison to competing technologies in use at present day, or of competing technologies under development worldwide.

Open Access July 28, 2013

Anaerobic wastewater treatment using anaerobic baffled bioreactor: a review

Siti Hassan, Irvan Dahlan

Page range: 389-399

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Abstract

Anaerobic wastewater treatment is receiving renewed interest because it offers a means to treat wastewater with lower energy investment. Because the microorganisms involved grow more slowly, such systems require clever design so that the microbes have sufficient time with the substrate to complete treatment without requiring enormous reactor volumes. The anaerobic baffled reactor has inherent advantages over single compartment reactors due to its circulation pattern that approaches a plug flow reactor. The physical configuration of the anaerobic baffled reactor enables significant modifications to be made; resulting in a reactor which is proficient of treating complex wastewaters which presently require only one unit, ultimately significant reducing capital costs. This paper also concerns about mechanism, kinetic and hydrodynamic studies of anaerobic digestion for future application of the anaerobic baffled reactor for wastewater treatment.

Open Access July 28, 2013

Flow structure and cooling behavior of air impingement on a target plate

Adnan Abdul Rasool, Faik Hamad

Page range: 400-409

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Abstract

An experimental data of flow field, pressure coefficient and heat transfer of a jet impinging normally on a flat target plate are presented. The measurements of temperatures and static pressures were carried out for flow from three orifices of 5, 10 and 20 mm diameter for orifice-to-target plate distances of 5, 10, 25, 50, 70, 100 and 120 mm from the orifice exit. The axial development of flow structure of the jet from the orifice was investigated by measuring the radial jet velocity distributions at the same axial distances used to measure heat transfer and static pressure. The results show that pressure coefficients distributions on the target plate are similar to the velocity distributions in the impinging jet which indicates the strong relationship between the two parameters. The pressure coefficients from large orifice diameter are higher than the values from the small orifice diameter for same orifice-to-target plate distance. The results also show a nonlinear increase of heat transfer rate with orifice size and the ratio of axial distance to orifice diameter (X/d). The nonlinear behaviour may be attributed to the complex nature of flow structure at the stagnation region. The high velocity gradients at the stagnation zone leads to higher turbulence and comparatively higher values of heat transfer rates for large orifice diameter.

Open Access July 28, 2013

The use of artificial neural networks to predict the muscle behavior

Patrik Kutilek, Slavka Viteckova, Zdenĕk Svoboda, Pavel Smrcka

Page range: 410-418

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Abstract

The aim of this article is to introduce methods of prediction of muscle behavior of the lower extremities based on artificial neural networks, which can be used for medical purposes. Our work focuses on predicting muscletendon forces and moments during human gait with the use of angle-time diagram. A group of healthy children and children with cerebral palsy were measured using a Vicon MoCap system. The kinematic data was recorded and the OpenSim software system was used to identify the joint angles, muscle-tendon forces and joint muscle moment, which are presented graphically with time diagrams. The musculus gastrocnemius medialis that is often studied in the context of cerebral palsy have been chosen to study the method of prediction. The diagrams of mean muscle-tendon force and mean moment are plotted and the data about the force-time and moment-time dependencies are used for training neural networks. The new way of prediction of muscle-tendon forces and moments based on neural networks was tested. Neural networks predicted the muscle forces and moments of healthy children and children with cerebral palsy. The designed method of prediction by neural networks could help to identify the difference between muscle behavior of healthy subjects and diseased subjects.

Open Access July 28, 2013

An exploration of FMCDM approach for evaluating the outcome/success of GSD projects

Arun Sangaiah, Arun Thangavelu

Page range: 419-435

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Abstract

This study presents a fuzzy multi-criteria decision making (FMCDM) approach for analyzing the influential factors affecting the outcome/success of global software development (GSD) projects. The main aim of this study is to demonstrate the potential of proposed methodology based on FMCDM which is used to measure the offshore/onsite teams’ partnership quality dimensions and underlying the influential factors towards the outcome of GSD projects. The uncertainty and subjective vagueness within the decision making process are dealing with fuzzy linguistic terms quantified in an interval scale [0,1]. The proposed FMDCM framework is used to determine the priority weights of partnership quality factors and rating the GSD project outcome/success from the service provider perspective into three dimensions: service quality, schedule and cost improvement. The predicted GSD project outcome values are obtained to facilitate organization and to determine the impact of offshore/on-site teams’ partnership quality towards success of GSD project outcome otherwise initiate actions to improve the GSD project outcome. This study established survey research method that involves thirty-eight critical influential factors evaluated by twenty software professionals for their assessment of GSD projects outcome in India.

Open Access July 28, 2013

Coordinated signal control for arterial intersections using fuzzy logic

Davood Kermanian, Assef Zare, Saeed Balochian

Page range: 436-445

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Abstract

Every day growth of the vehicles has become one of the biggest problems of urbanism especially in major cities. This can waste people’s time, increase the fuel consumption, air pollution, and increase the density of cars and vehicles. Fuzzy controllers have been widely used in many consumer products and industrial applications with success over the past two decades. This article proposes a comprehensive model of urban traffic network using state space equations and then using Fuzzy Logic Tool Box and SIMULINK Program MATLAB a fuzzy controller in order to optimize and coordinate signal control at two intersections at an arterial road. The fuzzy controller decides to extend, early cut or terminate a signal phase and phase sequence to ensure smooth flow of traffic with minimal waiting time and length of queue. Results show that the performance of the proposed traffic controller at novel fuzzy model is better that of conventional controllers under normal and abnormal traffic conditions.

Open Access July 28, 2013

A fractal circular polarized RFID tag antenna

Guesmi Chaouki, Abdelhak Ferchichi, Ali Gharsallah

Page range: 446-450

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Abstract

In this paper, we present a novel fractal antenna for radiofrequency identification (RFID) tags. The proposed antenna has a resonant frequency equal to 2.45GHz and circular polarization. The fractal technique was very useful to obtain a miniaturization of antenna size by more than 30%. The gain and directivity of the antenna are acceptable for the desired RFID application. All the results are obtained using CST Microwave simulation tool.

Open Access July 28, 2013

Functional variable method to study nonlinear evolution equations

Mostafa Eslami, Mohammad Mirzazadeh

Page range: 451-458

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Abstract

The functional variable method is a powerful solution method for obtaining exact solutions of nonlinear evolution equations. This method presents a wider applicability for handling nonlinear wave equations. In this paper, the functional variable method is used to construct exact solutions of Davey-Stewartson equation, generalized Zakharov equation, K(m, n) equation with generalized evolution term, (2 + 1)-dimensional long-wave-short-wave resonance interaction equation and nonlinear Schrödinger equation with power law nonlinearity. The obtained solutions include solitary wave solutions, periodic wave solutions.

Open Access July 28, 2013

Elastic analysis of exponential FGM disks subjected to internal and external pressure

Mohammad Nejad, Majid Abedi, Mohammad Lotfian, Mehdi Ghannad

Page range: 459-465

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Abstract

Assuming exponential varying properties in the radial direction and constant Poisson’s ratio, a closed-form analytical solution based on the elasticity theory is obtained to elastic analysis of disks made of functionally graded materials (FGMs) subjected to internal and external pressure. Following this, radial displacement, radial stress, and circumferential stress profiles are plotted for different values of material inhomogeneity constant, as a function of radial direction. The displacements and stresses distributions are compared with the solutions of the finite element method (FEM) and comparison with the corresponding numerical solution indicates that the proposed solution has excellent convergence and accuracy.

Open Access July 28, 2013

Prediction and analysis of radial overcut in holes drilled by electrochemical machining process

Mehdi Tajdari, Saeed Chavoshi

Page range: 466-474

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Abstract

Radial overcut predictive models using multiple regression analysis, artificial neural network and co-active neurofuzzy inference system are developed to predict the radial overcut during electrochemical drilling with vacuum extraction of electrolyte. Four process parameters, electrolyte concentration, voltage, initial machining gap and tool feed rate, are selected to develop the models. The comparison between the results of the presented models shows that the artificial neural network and co-active neuro-fuzzy inference system models can predict the radial overcut with an average relative error of nearly 5%. Main effect and interaction plots are generated to study the effects of process parameters on the radial overcut. The analysis shows that the voltage, electrolyte concentration and tool feed rate have significant effect on radial overcut, respectively, while initial machining gap has a little effect. It is also found that the increase of the voltage and electrolyte concentration increases the radial overcut and the increase of the tool feed rate decreases the radial overcut.

Open Access July 28, 2013

Constructal design applied to the elastic buckling of thin plates with holes

Luiz Rocha, Liércio Isoldi, Mauro Vasconcellos Real, Elizaldo Santos, Anderson Correia, Giulio Lorenzini, Cesare Biserni

Page range: 475-483

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Abstract

Elastic buckling is an instability phenomenon that can occur if a slender and thin plate is subjected to axial compression. An important characteristic of the buckling is that the instability may occur at a stress level that is substantially lower than the material yield strength. Besides, the presence of holes in structural plate elements is common. However these perforations cause a redistribution in plate membrane stresses, significantly altering their stability. In this paper the Bejan’s Constructal Design was employed to optimize the geometry of simply supported, rectangular, thin perforated plates subjected to the elastic buckling. Three different centered hole shapes were considered: elliptical, rectangular and diamond. The objective function was to maximize the critical buckling load. The degree of freedom H/L (ratio between width and length of the plate) was kept constant, while H0/L0 (ratio between the characteristic dimensions of the holes) was optimized for several hole volume fractions (ϕ). A numerical model employing the Lanczos method and based on the finite element method was used. The results showed that, for lower values of ϕ the optimum geometry is the diamond hole. For intermediate and higher values of ϕ, the elliptical and rectangular hole, respectively, led to the best performance.

Open Access July 28, 2013

Microstructure and crack resistance of low carbon Cr-Ni and Cr-Ni-W steel after austempering

Tatyana Avdjieva, Gichka Tsutsumanova, Stoyan Russev, Konstantin Staevski

Page range: 484-491

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Abstract

The microstructure of the low carbon Cr-Ni steel after slow cooling from austenization temperature represents a mix of granulated bainite with islands from carbon-rich martensite and carbon-poor austenite. After quick cooling throwing in salt bath from austenization temperature the microstructure is lath bainite. However, in the same treatment conditions, the microstructure of the low carbon Cr-Ni-W steel is different — clusters consist from lath ferrite and retained austenite, disposed in the frame of parent’s austenite grains. The cooling velocity has no effect upon the structure making. The impact toughness of the steel with tungsten content is bigger than the steel without tungsten.

Open Access July 28, 2013

Some functional properties of composite material based on scrap tires

Renate Plesuma, Laimonis Malers

Page range: 492-496

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Abstract

The utilization of scrap tires still obtains a remarkable importance from the aspect of unloading the environment from non-degradable waste [1]. One of the most prospective ways for scrap tires reuse is a production of composite materials [2] This research must be considered as a continuation of previous investigations [3, 4]. It is devoted to the clarification of some functional properties, which are considered important for the view of practical applications, of the composite material. Some functional properties of the material were investigated, for instance, the compressive stress at different extent of deformation of sample (till 67% of initial thickness) (LVS EN 826) [5] and the resistance to UV radiation (modified method based on LVS EN 14836) [6]. Experiments were realized on the purposefully selected samples. The results were evaluated in the correlation with potential changes of Shore C hardness (Shore scale, ISO 7619-1, ISO 868) [7, 8]. The results showed noticeable resistance of the composite material against the mechanical influence and ultraviolet (UV) radiation. The correlation with the composition of the material, activity of binder, definite technological parameters, and the conditions supported during the production, were determined. It was estimated that selected properties and characteristics of the material are strongly dependent from the composition and technological parameters used in production of the composite material, and from the size of rubber crumb. Obtained results show possibility to attain desirable changes in the composite material properties by changing both the composition and technological parameters of examined material.

Open Access July 28, 2013

Urban drainage control applying rational method and geographic information technologies

Beatriz Aldalur, Alicia Campo, Sandra Fernández

Page range: 497-512

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Abstract

The objective of this study is to develop a method of controlling urban drainages in the town of Ingeniero White motivated by the problems arising as a result of floods, water logging and the combination of southeasterly and high tides. A Rational Method was applied to control urban watersheds and used tools of Geographic Information Technology (GIT). A Geographic Information System was developed on the basis of 28 panchromatic aerial photographs of 2005. They were georeferenced with control points measured with Global Positioning Systems (basin: 6 km2). Flow rates of basins and sub-basins were calculated and it was verified that the existing open channels have a low slope with the presence of permanent water and generate stagnation of water favored by the presence of trash. It is proposed for the output of storm drains, the use of an existing channel to evacuate the flow. The solution proposed in this work is complemented by the placement of three pumping stations: one on a channel to drain rain water which will allow the drain of the excess water from the lower area where is located the Ingeniero White city and the two others that will drain the excess liquid from the port area.

Open Access July 28, 2013

Integration of thermophysiological body model in CFD

George Pichurov, Peter Stankov

Page range: 513-521

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Abstract

A two-node mathematical model of the human thermophysiological system has been integrated into a Computational Fluid Dynamic (CFD) simulation of the airflow in a room. Temperature inputs from the CFD are used by the model to evaluate the dry and latent heat flux from the body surface and output them as boundary conditions. This is an iterative process and convergence is ensured by under-relaxation of the latent heat flux. The model also considers the dry and latent heat resistance of clothing. Numerical predictions of the body heat loss and airflow are compared against physical measurements in a climate chamber. Good agreement was observed when using the low Reynolds number turbulence model. The integrated simulation performs well under wide set of conditions, predicting body core and skin temperature, blood flow, skin wittedness, as well as the transfer of heat and moisture released by the body into the room.

Open Access July 28, 2013

Engineering properties of cement mortar with pond ash in South Korea as construction materials: from waste to concrete

Sang Jung, Seung-Jun Kwon

Page range: 522-533

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Abstract

Among the wastes from coal combustion product, only fly ash is widely used for mineral mixture in concrete for its various advantages. However the other wastes including bottom ash, so called PA (pond ash) are limitedly reused for reclamation. In this paper, the engineering properties of domestic pond ash which has been used for reclamation are experimentally studied. For this, two reclamation sites (DH and TA) in South Korea are selected, and two domestic PAs are obtained. Cement mortar with two different w/c (water to cement) ratios and 3 different replacement ratios (0%, 30%, and 60%) of sand are prepared for the tests. For workability and physical properties of PA cement mortar, several tests like flow, setting time, and compressive strength are evaluated. Several durability tests including porosity measuring, freezing and thawing, chloride migration, and accelerated carbonation are also performed. Through the tests, PA (especially from DH area) in surface saturated condition is evaluated to have internal curing action which leads to reasonable strength development and durability performances. The results show a potential applicability of PA to concrete aggregate, which can reduce consuming natural resources and lead to active reutilization of coal product waste.

Open Access July 28, 2013

Correlation between permanent deformation-related performance parameters of asphalt concrete mixes and binders

Kálmán Adorjányi, Péter Füleki

Page range: 534-540

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Abstract

This paper examines methods to predict the performance of hot asphalt concrete mixes based on performance parameters of binders. Specifically, relationships between binder parameters determined from multiple stress creep and recovery tests were correlated to the creep parameters of hot asphalt concrete mixes obtained from cyclic load compression testing. For the determination of creep parameters, a modified expression of the creep curve is proposed to cover the entire spectrum of permanent deformation; including the tertiary creep phase. Non-recoverable compliance, unrecovered strain, and recoverable strain of binders show good correlation to creep parameters of hot asphalt concrete mixes such as creep rate and high temperature performance ratio. Additionally, unrecovered strain and non-recoverable compliance of binders correlates well with mean rut depth of asphalt concrete mixes. However, no correlation has been detected between the difference in non-recoverable compliance of binders and permanent deformation parameters of asphalt concrete mixes.

Open Access July 28, 2013

Hydrodynamic perspectives of soil scour in fluvial environment

Sarik Salim, Ravindra Jayaratne

Page range: 541-548

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Abstract

The major concern for many hydraulic structures is the effect of scour at the toe, when the racing floodwater scours away the bed just downstream of the piers. Therefore, understanding the soil-hydrodynamic interaction needs to be investigated. In this study, a series of 2D laboratory tests have been carried out to study the likelihood of soil scour due to the soil-hydrodynamic interaction and influence of sediment properties. Characteristics such as sediment deposition patterns, longitudinal/lateral spreading length/area, and bed scour profiles for three sediment diameters (i.e. 0.26, 0.30 and 2.40 mm) under dry and wet soil conditions are studied intensively. Experimental results revealed that soil of identical diameters under wet and dry conditions caused significant changes in soil scour rate and deposition patterns. Transport rates in dry condition were much slower than wet condition. It was observed that, for the same flow condition, different soils gave different long term equilibrium deposition patterns due to the grain size distribution and particle shape. Eddies were generated behind the soil samples which resulted in forming a series of ‘crescent’ zones. Findings of this study could offer a qualitative outline of the effects of various parameters to demonstrate a better representation of estimating scour rate in fluvial condition.

Open Access July 28, 2013

Seismic analysis of high arch dams considering contraction-peripheral joints coupled effects

Mohammad Hariri-Ardebili, Hasan Mirzabozorg, M. Kianoush

Page range: 549-564

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Abstract

Dam-reservoir interaction is one of the classic coupled problems in which two various environments with different physical characteristics are in contact with each other on interface boundary. Consideration of such interaction is important in design of new dams as well as on safety evaluation of the existing ones. In the present study, the effect of hydrodynamic pressures at various reservoir operational levels on seismic behavior of an arch dam is investigated. Dez ultra-high arch dam in Iran was selected as case study and all contraction and peripheral joints were simulated using node-to-node contact elements which have the ability of opening/closing and tangential movement. In addition, stage construction effects including joint grouting based on available construction reports were considered. The reservoir was assumed to be compressible and the foundation rock was modeled to account for its flexibility. The TABAS earthquake record was used to excite the finite element model of dam-reservoir-foundation system. It was found that dam-reservoir interaction has significant structural effects on the system and generally, operating the considered arch dam at different water levels can highly affects the distribution of the crack prone area under the maximum credible earthquake.

About this journal

Open Engineering publishes research results of wide interest in emerging interdisciplinary and traditional engineering fields, including:

electrical and computer engineering,
civil and environmental engineering,
mechanical and aerospace engineering,
material science and engineering.

The journal is designed to facilitate the exchange of innovative and interdisciplinary ideas between researchers from different countries. Open Engineering is a peer-reviewed, English language journal. Additionally, each published article is widely promoted to researchers working in the same field.

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