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1 – 6 of 6O.M. Haddad, M. Abu‐Qudais, B.A/K Abu‐Hijleh and A.M. Maqableh
This study is focused on the local entropy generation of steady two‐dimensional symmetric flow past a parabolic cylinder in a uniform stream parallel to its axis. The effect of…
Abstract
This study is focused on the local entropy generation of steady two‐dimensional symmetric flow past a parabolic cylinder in a uniform stream parallel to its axis. The effect of both Reynolds number (Re) and temperature difference between the cylinder wall and the freestream (ΔT) on thermal, viscous, and total entropy generation is investigated for different values of Prandtl number (Pr) and Mach number (Ma). It was found that the thermal entropy generation increased as the temperature difference increased, while the viscous entropy generation decreased as Reynolds number increased. The results also showed that increasing Prandtl number or Mach number increased both the viscous and thermal contributions to the entropy generation.
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O.M. Haddad, M. Abu‐Qudais and A.M. Maqableh
Numerical solutions are presented for steady two‐dimensional symmetric flow past parabolic bodies in a uniform stream parallel to its axis. For this study, the full Navier‐Stokes…
Abstract
Numerical solutions are presented for steady two‐dimensional symmetric flow past parabolic bodies in a uniform stream parallel to its axis. For this study, the full Navier‐Stokes equations and energy equation in parabolic coordinates were solved. A second order accurate finite difference scheme on a non‐uniform grid was used. The solution domain does not exclude the leading edge region as it is usually done with boundary layer flows. A wide range of Reynolds number (Re) is studied for different values of Prandtl number (Pr). It is found that the average Nusselt number (Nu) increases as (Pr) increases meanwhile, (Nu) decreases with the increase in (Re).
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Dipankar Chatterjee and Suman Chakraborty
The purpose of this paper is to carry out a systematic energy analysis for predicting the first and second law efficiencies and the entropy generation during a laser surface…
Abstract
Purpose
The purpose of this paper is to carry out a systematic energy analysis for predicting the first and second law efficiencies and the entropy generation during a laser surface alloying (LSA) process.
Design/methodology/approach
A three‐dimensional transient macroscopic numerical model is developed to describe the turbulent transport phenomena during a typical LSA process and subsequently, the energy analysis is carried out to predict the entropy generation as well as the first and second law efficiencies. A modified k–ε model is used to address turbulent molten metal‐pool convection. The phase change aspects are addressed using a modified enthalpy‐porosity technique. A kinetic theory approach is adopted for modelling evaporation from the top surface of the molten pool.
Findings
It is found that the heat transfer due to the strong temperature gradient is mainly responsible for the irreversible degradation of energy in the form of entropy production and the flow and mass transfer effects are less important for this type of phase change problem. The first and second law efficiencies are found to increase with effective heat input and remain independent of the powder feed rate. With the scanning speed, the first law efficiency increases whereas the second law efficiency decreases.
Research limitations/implications
The top surface undulations are not taken care of in this model which is a reasonable approximation.
Practical implications
The results obtained will eventually lead to an optimized estimation of laser parameters (such as laser power, scanning speed, etc.), which in turn improves the process control and reduces the cost substantially.
Originality/value
This paper provides essential information for modelling solid–liquid phase transition as well as a systematic analysis for entropy generation prediction.
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Huthaifa Al-Hazaima, Mary Low and Umesh Sharma
This paper aims to examine the perceptions of salient stakeholders in Jordan concerning the importance of integrating sustainability education (SE) into the accounting curriculum.
Abstract
Purpose
This paper aims to examine the perceptions of salient stakeholders in Jordan concerning the importance of integrating sustainability education (SE) into the accounting curriculum.
Design/methodology/approach
This paper uses salient stakeholder theory as a lens and seeks to explore the possible integration of SE into the Jordanian tertiary accounting curriculum. A final sample of 702 salient stakeholders including university accounting educators, accounting students, industry accountants, government representatives and accounting association professional members were used to glean an insight of their views and the extent to which sustainability is present in accounting education.
Findings
Findings indicate that there is a strong belief by these salient stakeholders that there is significant importance for the integration of SE into the accounting curriculum in Jordanian universities. There is concern that the current curriculum does not meet the educational needs of future accountants and business executives from a sustainability perspective.
Research limitations/implications
This study contributes to the research debate on the competencies crisis in accounting education by focusing on the lack of SE in the accounting curriculum. This study draws attention to the need of up-skilling and applied knowledge in this critical area. There are strong viewpoints from the salient stakeholders in this study. They emphasise that a progressive education solution is required and which integrates SE into the accounting curriculum.
Practical implications
The research is useful to accounting educators, professional accounting associations, industry, accounting students and the government. The salient stakeholders in Jordan wish to include SE within the accounting curriculum. This would lead to future accountants and business executives having stronger competencies to respond in a resilient and resourceful manner to changes in the way business is conducted, especially in an area where societal and environmental impacts are highly scrutinised.
Originality/value
This study provides evidence on how salient stakeholders of an emerging economy can influence, provide guidance and leadership in integrating SE in the accounting curriculum. Engaging actively and extensively with research studies such as this allows them to voice their opinions about the importance of sustainability and how their country can better engage in this increasingly important field.
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This study aims to utilized the item response theory (IRT) rating scale model to analyze students’ perceptions of assessment practices in two universities: one in Jordan and the…
Abstract
Purpose
This study aims to utilized the item response theory (IRT) rating scale model to analyze students’ perceptions of assessment practices in two universities: one in Jordan and the other in the USA. The sample of the study consisted of 506 university students selected from both universities. Results show that the two universities still focus on paper-pencil testing to assess students’ learning outcomes. The study recommends that higher education institutes should encourage their teachers to use different assessment methods to assess students’ learning outcomes.
Design/methodology/approach
The convenience sample consisted of 506 selected university students from the USA and Jordan, and participants were distributed according to their educational levels, thus: 83 freshmen, 139 sophomores, 157 juniors and 59 seniors. (Note: some students from both universities did not report their gender and/or their educational level). The USA university sample consisted of 219 students from three colleges at a major university in the southeast of the USA studying for arts and sciences, education and commerce and business qualifications, of whom 43 were males and 173 were females. The study used the Students Perception of Assessment Practices Inventory developed by Alquraan (2007), and for the purpose of this study, the RUMM2020 program was used for its rating scale model.
Findings
Both universities, in Jordan and the USA, still focus more on the developmental (construction of assessment tasks), organizational and planning aspects of assessment processes than they do on assessments of learning and assessment methods (traditional and new assessment methods). The assessment practices that are used frequently in both universities based on the teachers sampled are: “(I27) I know what to study for the test in this class”, “(I6) Teacher provides a good environment during test administration” and “(I21) My teacher avoids interrupting students as they are taking tests”. This indicates that teachers in the selected universities have a tendency to focus on the administrative and communicative aspects of assessment (e.g. providing a good environment during test administration) more than on using different assessment methods (e.g. portfolios, new technology, computers, peer and self-assessment) or even using assessment practices that help students learn in different ways (e.g. assessing students’ prior knowledge and providing written feedback on the graded tests).
Originality/value
This is a cross-cultural study focus assessment of students learning in higher education.
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O.M. Haddad, M.A. Al‐Nimr and M.A. Abu‐Ayyad
Numerical solutions are presented for steady two‐dimensional symmetric flow past a parabolic cylinder embedded in porous media. For this study, the full Navier–Stokes equations…
Abstract
Numerical solutions are presented for steady two‐dimensional symmetric flow past a parabolic cylinder embedded in porous media. For this study, the full Navier–Stokes equations (combined with the Brinkman–Forchheimer‐extended Darcy model) and energy equation in parabolic coordinates were solved. A second order accurate finite difference scheme on a non‐uniform grid was used. A wide range of Reynolds number (Re) is studied for different values of Prandtl number (Pr). It is found that the pressure, skin friction and Nusselt number decreases as the Darcy number (Da) decreases and/or the Inertia parameter (Λ) increases.
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