K. Aboubi, L. Robillard, E. Bilgen and P. Vasseur
The present study deals with two‐dimensional convective motion due tothe effect of a centrifugal force field on a fluid contained between twohorizontal concentric cylinders, for…
Abstract
The present study deals with two‐dimensional convective motion due to the effect of a centrifugal force field on a fluid contained between two horizontal concentric cylinders, for the particular case of an adiabatic inner boundary (zero heat flux) and a constant heat flux imposed on the outer boundary. The normal terrestrial gravity is considered negligible. Governing equations for a two‐dimensional flow field are solved using analytical and numerical techniques. Based on a concentric flow approximation, the analytical solution is obtained in terms of the Rayleigh number and the radius ratio. The numerical solution is based on a finite difference method. Results indicate that the flow field always consists of two symmetrical cells at incipient convection even at radius ratios near unity. A good agreement is found between the analytical and numerical solutions at finite amplitude convection.
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Isaac Cheah, Min Teah, Sean Lee and Zachary Davies
This study aims to provide a conceptual framework to investigate the effects of consumer attitudes toward brands and attitudes toward a series of fashion oriented print…
Abstract
Purpose
This study aims to provide a conceptual framework to investigate the effects of consumer attitudes toward brands and attitudes toward a series of fashion oriented print advertisements with and without homosexual themes, on consumer willingness to buy from brands. The influence of consumer skepticism and inferences of manipulative intent (IMI) as moderators between these variables is also investigated. This study also closes various research gaps identified within the literature.
Design/methodology/approach
A self-administered survey instrument was designed using established scales to collect data through an online questionnaire. Fashion advertisements namely one advertisement representing homosexual content and one heterosexual advertisement were used in the study within subjects (e.g. male and female) design. Statistical techniques, specifically factor analysis, regressions and multiple regressions are used to analyze the data.
Findings
The findings indicate significant and positive relationships between attitude toward the brand and advertisement as well as willingness to buy for both males and females. The moderation analyses noted that consumer skepticism enhanced the relationship between attitude toward the brand and attitude toward the advertisement, but weakened the relationship between attitude toward the advertisement and willingness to buy, only for the female cohort. Similarly, a weakening effect of IMI was noted on the relationship between attitude toward the advertisement and willingness to buy.
Research limitations/implications
The current study contributes to the literature on homosexual imagery in advertising. In applying the persuasion knowledge model, the current study demonstrates the applicability of the model to homosexual themes in fashion advertising while accounting for the effects of consumer skepticism and IMI.
Practical implications
The current research highlights the importance of accounting for gender differences when introducing homosexual themes in fashion advertisements. Heterosexual males and females differ in their attitudes toward homosexual themes in fashion advertising, as well as how skeptical they are with regards to the motives of the advertiser. While a great deal of acceptance is already present in today's society, these differences still need to be accounted for in future fashion advertising campaigns.
Originality/value
The present study represents an examination of consumer responses to a series of fashion advertisements in Australia and provides useful implications to marketers of fashion products. The study further contributes to the literature on consumer skepticism and IMI with regards to cause-related advertising.
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Richard J. Sebastian and Bill Davison
To help procurement professionals identify the root causes of contract administration problems, we present an organizational behavior problem solving conceptual framework which…
Abstract
To help procurement professionals identify the root causes of contract administration problems, we present an organizational behavior problem solving conceptual framework which consists of a comprehensive exposition of potential personal (e.g., personality) and environmental (e.g., technology) causes of behavior. We then illustrate how the causal factors from the framework can be mapped to the procurement process and its problems. We expect that procurement professionals will be able to use the framework to identify root causes in post-mortem analyses of contracts or elsewhere in the procurement process to mitigate risks. We also expect that management will use the framework to address the organizational behavior root causes of problems, thereby improving the systems and processes it controls or influences and, in turn, minimizing or eliminating contract administration risks. Future research can evaluate the usefulness of the framework.
M. HASNAOUI, P. VASSEUR and E. BILGEN
Thermally driven flow in a tall inclined cavity bounded by porous layers is studied analytically and numerically. A constant heat flux is applied for heating and cooling of two…
Abstract
Thermally driven flow in a tall inclined cavity bounded by porous layers is studied analytically and numerically. A constant heat flux is applied for heating and cooling of two opposing walls of the cavity, while the other two are insulated. The Beavers—Joseph slip condition on velocity is applied at the interface between the fluid and porous layers. An analytical solution is obtained by assuming parallel flow in the core region of the cavity and a numerical solution by solving the complete governing equations. The flow and heat transfer variables are obtained in terms of the Rayleigh number, Ra, slip condition parameter N and angle of inclination of the cavity Φ. The critical Rayleigh numbers for the onset of convection in a layer heated from below are predicted for various hydrodynamic boundary conditions. The results for a fluid layer bounded by solid walls (N → ∞) and by free surfaces (N → 0) emerge from the present analysis as limiting cases.
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K. Aboubi, L. Robillard and P. Vasseur
The natural two‐dimensional convection taking place between horizontal concentric cylinders filled with a satured anisotropic porous medium is studied numerically. The anisotropy…
Abstract
The natural two‐dimensional convection taking place between horizontal concentric cylinders filled with a satured anisotropic porous medium is studied numerically. The anisotropy concerns exclusively the permeability. Isothermal boundary conditions are applied on both inner and outer boundaries, with the outer boundary being warmer. The effects of the anisotropic permeability ratio K*, of the orientation angle of the principal axes defined by γ, and of the Rayleigh number Ra* on the flow and heat transfer are investigated. Results indicate that a net circulating flow around the annulus is generated, except for values of γ that preserve the symmetry of flow conditions with respect to the vertical diameter. It is also shown that the anisotropic part of the resistivity tensor is equivalent to a magnetic resistivity tensor.
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The stability of two‐dimensional natural convection of water near its density maximum (cold water) inside a vertical rectangular enclosure with an aspect ratio of eight is…
Abstract
The stability of two‐dimensional natural convection of water near its density maximum (cold water) inside a vertical rectangular enclosure with an aspect ratio of eight is investigated via a series of direct numerical simulations. The simulations aim to clarify, under the influence of density inversion, the physical nature of the instability mechanism responsible for the laminar buoyancy‐driven flow transition from a steady state to an oscillatory state in the enclosure filled with cold water. Two values of the density inversion parameter, m= 0.4 and 0.5, where the density inversion of cold water may exert strong influence on the flow, are considered in the present study. The results show that the transition from steady state to periodically oscillatory convection arises in the cold‐water‐filled enclosure through a Hopf bifurcation. The oscillatory convection in the water‐filled enclosure for both values of m is found to feature an oscillatory multicellular structure within the contra‐rotating bicellular flow regions. A traveling wave motion accordingly results along the maximum density contour, which demarcates the contra‐rotating bicellular flows in the enclosure. For both cases the nature of transition into unsteadiness is found to be buoyancy‐driven. The critical Rayleigh number for the bifurcation at m = 0.4 is found to be markedly higher than that at m = 0.5.
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Krishna Roy, Asis Giri and Biplab Das
The paper aims to investigate the influence of the angle of inclination on mixed convection heat transfer from rectangular plated shrouded fin array computationally. This study…
Abstract
Purpose
The paper aims to investigate the influence of the angle of inclination on mixed convection heat transfer from rectangular plated shrouded fin array computationally. This study has got applications in the various thermal field such as cooling, solar thermal and so on.
Design/methodology/approach
A computational study is made to evaluate the thermal performance in an inclined channel.
Findings
Increase in clearance from 0.01 to 0.25 results in an increase of local Nusselt number by is as high as 15% near the exit. At a higher value of Gr with an increase in C* from 0.10, Nu is found to increase by 5.5%. Increase in Gr by 1.37 times results in enhancement of Nu by a maximum of 25-30%. Around 10% increase in overall Nu value is observed with an increase in inclination (i.e. from 30° to 60°).
Practical implications
This study has got applications in the various thermal field such as cooling, solar thermal and so on.
Originality/value
Entry region mixed convection in a shrouded inclined finned channel is performed.
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Mixed recirculatory flow in the annuli of stationary and rotatinghorizontal cylinders were studied numerically. A set of distorted‘false transient’ parameters were introduced to…
Abstract
Mixed recirculatory flow in the annuli of stationary and rotating horizontal cylinders were studied numerically. A set of distorted ‘false transient’ parameters were introduced to speed up the steady state solution of the unsteady vorticity, energy and stream function—vorticity equations. The inner cylinder of the annuli is assumed heated and rotating at Reynolds numbers that exclude the effects of centrifugal acceleration and three‐dimensional Taylor vortices. The Prandtl number considered is in the range of 0.01 to 1.0 and Rayleigh number in the range of 102 to 106. Radius ratios of the cylinders considered are 1.25, 2.5 and 5.0. For a radius ratio of 2.5, inner cylinder rotation in the Reynolds number range of 0 to 1120 was considered. Vertical eccentricities in the range of ±2/3 were studied for cases of the rotating inner cylinder. Numerical experiments show that the mean Nusselt number increases with Rayleigh number for both cases of concentric and eccentric stationary inner cylinder. At a Prandtl number of order 1.0 with a fixed Rayleigh number, when the inner cylinder is made to rotate, the mean Nusselt number decreases throughout the flow. At lower Prandtl number of the order 0.1 to 0.01, the mean Nusselt number remained fairly constant with respect to the rotational Reynolds number.
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Numerical simulations have been performed for three‐dimensional natural convection of water near its maximum‐density (cold water) inside rectangular enclosures with differential…
Abstract
Numerical simulations have been performed for three‐dimensional natural convection of water near its maximum‐density (cold water) inside rectangular enclosures with differential heating at the vertical (left and right) walls. The horizontal (top and bottom) walls and the lateral (front and rear) walls are taken as insulated. Computations are performed for the buoyancy‐driven convection of cold water with density inversion parameter θm = 0.5 in the enclosures with aspect ratio (height/width) Ay = 8 and depth ratios (depth/width) Az = 0.5, 1, and 2. The influence of the depth ratio on the onset of oscillatory convection in a cold‐water‐filled enclosure is investigated. The presence of the lateral walls tends to suppress the onset of unsteadiness in the convective flow. The main features of the oscillatory convection flow and temperature fields as well as the instability mechanism in the three‐dimensional enclosure were similar to those found in the two‐dimensional model. However, there exists a strong three‐dimensionality in the spatial distribution of the fluctuation amplitude. With the decrease of the depth ratio, the damping effect of the lateral walls becomes increasingly pronounced, leading to a reduced heat transfer rate.