bluuebunny/crossref_metadata_2025_split huggingface dataset:
Least-squares finite element solution of Euler equations with H-type mesh refinement and coarsening on triangular elements
Authors: Yigit Akargun Hayri , Sert Cuneyt 
Published: November 2014

Purpose
– The purpose of this paper is to demonstrate successful use of least-squares finite element method (LSFEM) with h-type mesh refinement and coarsening for the solution of two-dimensional, inviscid, compressible flows.

Design/methodology/approach
– Unsteady Euler equations are discretized on meshes of linear and quadratic triangular and quadrilateral elements using LSFEM. Backward Euler scheme is used for time discretization. For the refinement of linear triangular elements, a modified version of the simple bisection algorithm is used. Mesh coarsening is performed with the edge collapsing technique. Pressure gradient-based error estimation is used for refinement and coarsening decision. The developed solver is tested with flow over a circular bump, flow over a ramp and flow through a scramjet inlet problems.

Findings
– Pressure difference based error estimator, modified simple bisection method for mesh refinement and edge collapsing method for mesh coarsening are shown to work properly with the LSFEM formulation. With the proper use of mesh adaptation, time and effort necessary to prepare a good initial mesh reduces and mesh independency control of the final solution is automatically taken care of.

Originality/value
– LSFEM is used for the first time for the solution of inviscid compressible flows with h-type mesh refinement and coarsening on triangular elements. It is shown that, when coupled with mesh adaptation, inherent viscous dissipation of LSFEM technique is no longer an issue for accurate shock capturing without unphysical oscillations.
Numerical Simulation of PCM melting over a wavy surface
Authors: Kousksou Tarik , Mahdaoui Mustapha , Ahmed Arid , Batina Jean 
Published: November 2014

Purpose
– The purpose of this paper is to conduct a numerical study to analyze the melting process along a vertical wavy surface with uniform surface temperature.

Design/methodology/approach
– The cavity horizontal walls are insulated while the left hot wavy wall and the right cold wall are maintained at temperatures, TH=38.3°C and TC=28.3°C, respectively. The enclosure was filled by solid Gallium initially at temperature TC. A numerical code is developed using an unstructured finite-volume method and an enthalpy porosity technique to solve for natural convection coupled to solid-liquid phase change. The validity of the numerical code used is ascertained by comparing the results with previously published results.

Findings
– The effect of number of wavy surface undulation and amplitude of the wavy surface on the flow structure and heat transfer characteristics is investigated in detail. The numerical results show that the enhanced total heat transfer rate seems to depend on the amplitude of the wavy surface.

Originality/value
– Flow and heat transfer from irregular surfaces are often encountered in many engineering applications to enhance heat transfer such as micro-electronic devices, flat plate solar collectors and flat-plate condensers in refrigerators, etc. Roughened surfaces could be used in latent storage systems where the wall heat flux is known. One of the reasons why a roughened surface is more efficient in heat transfer is its capability to promote fluid motion near the surface; in this way a complex wavy surface is expected to promote a larger heat transfer rate than a flat plate. This complex geometry will promote a correspondingly complicated motion in the fluid near the surface; this motion is described by the nonlinear boundary-layer equations.
Identifying a time-dependent heat source with nonlocal boundary and overdetermination conditions by the variational iteration method
Authors: Zhou Guanglu , Wu Boying 
Published: November 2014

Purpose
– The purpose of this paper is to investigate the inverse problem of determining a time-dependent heat source in a parabolic equation with nonlocal boundary and integral overdetermination conditions.

Design/methodology/approach
– The variational iteration method (VIM) is employed as a numerical technique to develop numerical solution. A numerical example is presented to illustrate the advantages of the method.

Findings
– Using this method, we obtain the exact solution of this problem. Whether or not there is a noisy overdetermination data, our numerical results are stable. Thus the VIM is suitable for finding the approximation solution of the problem.

Originality/value
– This method is based on the use of Lagrange multipliers for the identification of optimal values of parameters in a functional and gives rapidly convergent successive approximations of the exact solution if such a solution exists.
Magnetohydrodynamic (MHD) squeeze film characteristics between finite porous parallel rectangular plates with surface roughness
Authors: Kesavan Sundarammal , J. Chamkha Ali , Krishnan Narayanan Santhana 
Published: November 2014

Purpose
– The purpose of this paper is to consider magnetohydrodynamic (MHD) squeeze film characteristics between finite porous parallel rectangular plates with surface roughness.

Design/methodology/approach
– Based upon the MHD theory, this paper analyzes the surface roughness effect squeeze film characteristics between finite porous parallel rectangular plates lubricated with an electrically conducting fluid in the presence of a transverse magnetic field.

Findings
– It is found that the magnetic field effects characterized by the Hartmann number produce an increased value of the load carrying capacity and the response time as compared to the classical Newtonian lubricant case. The modified averaged stochastic Reynolds equation governing the squeeze film pressure is derived.

Research limitations/implications
– The present study has considered both Newtonian fluids and non-Newtonian liquids.

Practical implications
– The work represents a very useful source of information for researchers on the subject of MHD squeeze film with finite porous parallel rectangular plates lubricated with an electrically conducting fluid.

Originality/value
– This paper is relatively original and illustrates the squeeze film characteristics between finite porous parallel rectangular plates with MHD effects.
Monte Carlo simulation of aerosol evolution in a planar mixing layer
Authors: Zhou Kun , He Zhu 
Published: November 2014

Purpose
– The purpose of this paper is to investigate aerosol evolution in a planar mixing layer from a Lagrangian point of view. After using Monte Carlo (MC) method to simulate the evolution of aerosol dynamics along particles trajectories, the particles size distributions are obtained, which are unavailable in mostly used methods of moments.

Design/methodology/approach
– Nucleation and growth of dibutyl phthalate (DBP) particles are simulated using the quadrature method of moments in a planar mixing layer, where a fast hot stream with DBP vapor is mixing with a slow cool stream without vapor. Trajectories of aerosol particles are recorded. MC method is used to simulate the aerosol evolution along trajectories.

Findings
– Investigation on aerosol evolution along the trajectories prompts to classify these trajectories into three groups: first, trajectories away from the active nucleation zone; second, trajectories starting from the active nucleation zone; and third, trajectories crossing over the active nucleation zone. Particle size distributions (psds) along selected representative trajectories are investigated. The psd evolution exhibits interesting behavior due to the synthetic effects of nucleation and condensation. Condensation growth tends to narrow down the psd, and form a sharp front on the side of big particle size. Nucleation is able to broaden the psd through generating the smallest particles. The duration and strength of nucleation have significant effect on the shape of psd.

Originality/value
– As far as the authors knowledge, it is the first simulation of aerosol evolution that takes a Lagrangian point of view, and uses MC simulation along particles trajectories to provide the particles size distribution.
Pressure and flow propagation rule beyond original premixed area of methane-air in tunnel
Authors: Zhang Qi , Ma Qiuju 
Published: November 2014

Purpose
– Whether a fire can be initiated in an explosion accident depends on the explosion and deflagration process. In the methane-air explosion in a tunnel, the flame accelerates from the ignition point. However, where it begins to decelerate is not clear. The purpose of this paper is to examine the explosion overpressure, flow and flame propagation beyond the premixed area of methane-air in a tunnel.

Design/methodology/approach
– The numerical simulation was used to study the explosion processes of methane-air mixtures in a tunnel. Based on the numerical simulation and its analysis, the explosion overpressure, flow and flame propagation rules beyond the premixed area were demonstrated for a methane-air explosion.

Findings
– The peak overpressure of methane-air mixture explosion was observed to reach its maximum beyond the original premixed area of methane-air. The hazardous effects beyond the premixed area may be stronger than those within the premixed area for a methane-air explosion in a tunnel. Under the conditions of this study, the ratio between the length of combustion area (40 m) and that of original premixed area (28 m) reaches 1.43.

Originality/value
– Little attention has been devoted to investigating the explosion overpressure, flow and flam propagations beyond the original premixed area of methane-air in a tunnel. Based on the numerical simulation and the analysis, the propagation rule of overpressure wave and flow inside and outside the space occupied by methane/air mixture at the volume fraction of 9.5 percent in a tunnel were obtained in this work.
Numerical study of flow around and through a porous diamond cylinder in different apex angles
Authors: Rashidi Saman , Masoodi Reza , Bovand Masoud , Sadegh Valipour Mohammad 
Published: November 2014

Purpose
– The purpose of this paper is to study steady, laminar, and two-dimensional flow around and through a porous diamond cylinder.

Design/methodology/approach
– The governing equations are written for two zones: the clear fluid zone and the porous zone. For the porous zone, the modified Navier-Stokes equations, including Darcy, Brinkman, and Forcheimer terms are used. The governing equations are solved numerically using a finite volume approach.

Findings
– It was found that as the apex angle and Reynolds number decreases the wake length decreases and the separation is delayed.

Originality/value
– There is no published research in the literature about flow around and into porous diamond cylinders to study the effect of important parameters, such as apex angle, Darcy number, and Reynolds number.
Numerical analysis of laminar fluid flow characteristics past an elliptic cylinder
Authors: Paul Immanuvel , Arul Prakash K. , Vengadesan S. 
Published: November 2014

Purpose
– The purpose of this paper is to study the effects of Angle of Attack (AOA), Axis Ratio (AR) and Reynolds number (Re) on unsteady laminar flow over a stationary elliptic cylinder.

Design/methodology/approach
– The governing equations of fluid flow over the elliptic cylinder are solved numerically on a Cartesian grid using Projection method based Immersed Boundary technique. This numerical method is validated with the results available in open literature. This scheme eliminates the requirement of generating a new computational mesh upon varying any geometrical parameter such as AR or AOA, and thus reduces the computational time and cost.

Findings
– Different vortex shedding patterns behind the elliptic cylinder are identified and classified using time averaged centerline streamwise velocity profile, instantaneous vorticity contours and instantaneous streamline patterns. A parameter space graph is constructed in order to reveal the dependence of AR, AOA and Re on vortex shedding. Integral parameters of flow such as mean drag, mean lift coefficients and Strouhal number are calculated and the effect of AR, AOA and Re on them is studied using various pressure and streamline contours. Functional relationships of each of integral parameters with respect to AR, AOA and Re are proposed with minimum percentage error.

Practical implications
– The results obtained can be used to explain the characteristics of flow patterns behind slender to bluff elliptical cylinders which found applications in insect flight modeling, heat exchangers and energy conservation systems. The proposed functional relationships may be very useful for the practicing engineers in those fields.

Originality/value
– The results presented in this paper are important for the researchers in the area of bluff body flow. The dependence of AOA on vortex shedding and flow parameters was never reported in the literature. These results are original, new and important.
Impacts of climate change
Authors: H. Rao Purba , Thamizhvanan Arun 
Published: November 2014

Purpose
– The purpose of this paper is to explore whether the private sector consider voluntary involvement in efforts to combat the impacts of climate change in the lines mitigation approaches and adaptation approaches. Today’s world has increasingly become aware of the adverse effects of climate change and its impact on the poor, though the latter impact is not that well known. To address these impacts, recommendations exist that follow two different though interrelated approaches – mitigation and adaptation.

Design/methodology/approach
– Using a survey questionnaire as the research instrument and a sampling frame of 350 junior corporate executives, an empirical study was conducted in the Chennai area in southern part of India to evaluate/measure the linkages between awareness to climate change, its impact on the poor and the willingness of private sector to act on adaptation as well as mitigation strategies.

Findings
– From the data analysis, it emerges that there is significant awareness about the impacts of climate change, though the awareness to vulnerability of the poor is not yet significant in Chennai area in the private sector. However, the study concludes that there does exist a significant linkage between awareness and the willingness to support adaptation strategies on the part of junior corporate executives.

Research limitations/implications
– The study is country specific because the research was carried out in a defined region in India.

Practical implications
– Because the study brought out the result that private sector was willing to participate in adaptation strategies, extensive awareness building can be carried out for corporate executives and plan out activities which will enable them to participate in adaptation strategies which would help the poor in India to help address the devastations caused by Climate Change from time to time.

Social implications
– Executives taking up the Climate Change adaptation strategy would help protect and benefit all communities especially the poor in the country. Companies operating in India would find an avenue to reach out in their efforts to touch communities around them. Employees in such companies may be organized and gathered together to participate in such reach-out activities on the part of the companies.

Originality/value
– This paper fulfils urgent need to inspire the corporate executives to take up initiatives related to climate change. The paper lays the groundwork on which an array of corporate activities can be developed to implement the adaptation strategies. Further extensive thinking can follow this research as to where and how exactly private sector can help.
Business agglomeration in tourist districts and hotel performance
Authors: Marco-Lajara Bartolomé , Claver-Cortés Enrique , Úbeda-García Mercedes 
Published: November 2014

Purpose
– The present paper aims to analyze how the performance of hotels located on the Spanish Mediterranean coast (peninsular and Balearic) and Canary coast is affected by the degree of business agglomeration in tourist districts. If agglomeration affects hotels positively, then the externalities generated in tourist districts will be relevant when locating an establishment. Otherwise, the reason why hotels group together geographically would be more related to the suitability of beaches as a tourist destination. The study also analyzes the impact that regions or autonomous communities have on hotel performance.

Design/methodology/approach
– The hypotheses are tested by multiple linear regression in which hotel profitability acts as the dependent variable which can be explained by independent variables such as the greater or lesser agglomeration of tourist companies at the destination and the autonomous region where the hotel is located.

Findings
– The results show that hotels situated at destinations with a higher degree of agglomeration are less profitable, probably due to the greater rivalry that exists among nearby competitors. However, in accordance with the theory of tourist districts, one could expect hotels located at destinations with a higher degree of agglomeration to be more profitable because of the greater externalities generated within the district. In this sense, it is possible that hotel location decisions were based more on the natural advantage model, where firms look for specialized inputs like beach or climate, than on production externalities models.

Research limitations/implications
– It was necessary to work with secondary information sources which contain no data about RevPar (revenue per available room) or GopPar (gross operating profit per available room), the hotel profitability measures most often used in research studies.

Practical implications
– The paper could be useful for hotel companies, when they are deciding on a location, and for public administrations.

Originality/value
– The present paper is original for several reasons. First, it is one of the first studies which applies the theory of industrial districts to the tourism sector, a line of research which is still in its early stages of development. Furthermore, the ISTAT methodology is applied for the first time to the identification of Spanish tourist districts. Also, various studies relate the degree of agglomeration to hotel profitability, but none so far have used the degree of company agglomeration within a tourist district, linking it to profitability.
Non-technical barriers for decentralised energy and energy efficient buildings
Authors: I. Goodier Chris , Chmutina Ksenia 
Published: November 2014

Purpose
– This paper aims to demonstrate the complex inter-relationship of non-technical barriers involved in the implementation of decentralised energy (DE) projects. To meet its ambitious 2050 target of 80 per cent carbon emission reduction, the UK needs to increase dramatically the wider uptake of DE systems. Many examples exist internationally of DE systems leading to enhanced carbon emissions reductions, including systems based not only on technological but also on more innovative policy, financial and social-economic approaches.

Design/methodology/approach
– Following semi-structured interviews with key stakeholders and thematic analysis with NVivo8, four exemplar international DE case studies have been investigated.

Findings
– The main non-technical barriers were not necessarily financial, as is often believed; governance barriers, such as out-of-date regulations or unreliable partners, can also play a critical role in a project’s success or failure. Social barriers such as public apathy and misinformation often affect a project’s operation. It is further hypothesised that non-technical barriers are often shaped by personal and/or organisational values related to consumption, abundance, trust and control. Finally, recommendations are provided on overcoming these barriers with regards replicating similar DE projects in the UK context.

Originality/value
– A systematic perspective is presented, which takes into account the possible interactions between the various barriers and demonstrates that to remove some of these barriers, it is important to understand and account for their varied and interconnected nature.
Discrete-time indirect adaptive fuzzy control for robot manipulators
Authors: Mehdi Fateh Mohammad , Azargoshasb Siamak 
Published: November 2014

Purpose
– The purpose of this paper is to design a discrete indirect adaptive fuzzy controller for a robotic manipulator. This paper addresses how to overcome the approximation error of the fuzzy system and uncertainties for asymptotic tracking control of robotic manipulators. The uncertainties include parametric uncertainty, un-modeled dynamics, discretization error and external disturbances.

Design/methodology/approach
– The proposed controller is model-free and voltage-based in the form of discrete-time Mamdani fuzzy controller. The parameters of fuzzy controller are adaptively tuned for asymptotic tracking of a desired trajectory. A robust control term is used to compensate the approximation error of the fuzzy system. An adaptive mechanism is derived based on the stability analysis.

Findings
– The proposed model-free discrete control is robust against all uncertainties associated with the robot manipulator and actuators. The approximation error of the fuzzy system is well compensated to achieve asymptotic tracking of the desired trajectories. Stability analysis and simulation results show its efficiency in the tracking control.

Originality/value
– A novel discrete indirect adaptive fuzzy controller is designed for electrically driven robot manipulators using the voltage control strategy. The novelty of this paper is compensating the approximation error of the fuzzy system and discretizing error for asymptotic tracking of the desired trajectory.