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This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

The increasing threat of global warming and climate change has been a major worldwide concern for more than two decades. As the achievement of sustainable economic growth has gradually become a major global concern both policy makers and researchers have given considerable attention over the years on the link among energy consumption, emissions and economic growth. In this study, following a solovian growth structure, the authors assume that the aggregate output depends on the stock of physical as well as human capital and energy or power. Depending on the sources, the energy can be categorised into cleaner input generated from renewable sources and a dirty input extracted from non-renewable resources having by-products like pollution. This study finds that less-developed countries (LDCs) failing to afford sufficient access to clean energy which in turn has deleterious impact on the human capital which cascades into low level of production, low saving and low per capita output forming a vicious loop. On the other side, the developed nations are better poised with access to clean energy and this is what is reflected in having larger reserve of human capital yielding higher production, higher income, higher saving and higher per capita capital stock in a circular process. This hence posits a clinching picturing divergence in per capital output and income between developed and less-developed nation mediated through degree of access to clean energy and thereof, the capacity to control emission. The convergence situation between the developed and the less-developed nations shows that each ends up with the relative energy mix below the threshold and it is not desirous for the world as a whole. In case of per capita emission, the divergence situation with the global level of emission is bit ambiguous.

Social entrepreneurship has played a significant role in reducing unemployment and poverty, fixing other social issues and environmental concerns. Although there is an increasing concern on social entrepreneurship by the public sector, practitioner and scholars, there are still limited studies on predicting the intention to become a social entrepreneur. Thus, investigating social entrepreneurship intention using a systematic literature review (SLR) approach is crucial due to the lack of systematisation and categorisation in this field. Therefore, this study aims to conduct a SLR to identify the antecedents of social entrepreneurial intention (SEI) used by the previous research. In this sense, this chapter carries out a systematic review of the literature on social entrepreneurship intentions. The review is guided by the PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses). After the identification and screening process, only 56 articles were qualified for further analysis. This SLR focused on articles that are using quantitative research and in the English language published in Scopus. Although there is no limitation in the timeline, the search string results found that the related articles were published between 2010 and 2020. From the thematic analysis, nine main themes were found. The themes are categorised based on the antecedents of SEI used by previous research. There are nine antecedents found: (1) perceived desirability and feasibility, (2) attitude, subjective norms and perceived behavioural control, (3) prior experience, (4) emotional factors, (5) self-efficacy, (6) personality, (7) support systems, (8) skills and competencies and (9) motivational factors. Further analysis of the themes has resulted in ten sub-themes. This chapter's contribution includes offering a clearer picture of the antecedents of social entrepreneurial intention that is still at its infancy stage. Additionally, this chapter managed to identify the research gaps and proposed future research agenda.

Entrepreneurial orientation (EO) and entrepreneurial intentions (EI) both are prominent factors in the entrepreneurship domain to predict entrepreneurial behavior. Despite the fact, association between the EO sub-aspects and EI, as well as the indirect influence of the personality characteristic (Openness), has not been extensively investigated. The focus of this research study is to examine the association between sub-dimensions of EO, proactiveness, risk-taking, and innovativeness, and EI incorporating personality trait openness to experience (OTE) as mediating variable. Data is gathered from 164 professional course students. For the data analysis purpose, mediation analysis, multiple regression and confirmatory factor analysis (CFA) have been performed. Findings imply that all the sub-aspects of EO are significantly correlated with EI and personality trait OTE acted as mediating construct in link amidst EO and EI. Practical and theoretical contribution have been discussed in this study.

Factors influential in directing Turkish manufacturers to exporting are discussed. The research shows that the majority of these companies started exports due to unexpected orders and entered this field as a result of domestic economic factors. For most of these companies, the domestic market preserves its significance. Therefore, a different marketing strategy is not implemented for exports. However, as size and export volume increase, a change in attitudes is observed, supporting the findings of previous empirical studies that involvement in export marketing is a sequential and gradual process.

Entrepreneurship has been one of the major pillars in our economy around the world. Aside from the aspiring and innovative entrepreneurs looking for like-minded collaborators to start new ventures that disrupt the business world, managers are increasingly looking for entrepreneurial graduates to tackle the ever-changing business landscape. There has been increasing consensus that entrepreneurship is not limited to being an attitude or a certain characteristic that one is born with, but a skill that can be developed through education. This can be seen in the sprung of entrepreneurship programs in various educational institutions, as well as dedicated entrepreneurship degrees in higher education. However, the information that each person is receiving can vary depending on their environment, and how they perceive and process the information can also be different. In addition, propensity to take actions to pursue the identified opportunities can also vary. Thus, how can the governments and universities work together in breeding the next generation of entrepreneurs? To answer our research question, we sampled 191 undergraduate students in a private university in Malaysia. We examined the relationship between entrepreneurial orientation, entrepreneurial self-efficacy, emotional intelligence, and entrepreneurial intention. Our findings contribute to future research with a more refined understanding of the factors affecting entrepreneurial intention, as well as practical implications for governments and higher education institutions on how they form an ecosystem in equipping future generations with entrepreneurialism.

Turbomachinery, including pumps, are mainly designed to extract/produce energy from/to the flow. A major challenge in the numerical simulation of turbomachinery is the inlet flow rate, which is routinely treated as a known boundary condition for simulation purposes but is properly a dependent output of the solution. As a consequence, the results from numerical simulations may be erroneous due to the incorrect specification of the discharge flow rate. Moreover, the transient behavior of the pumps in their initial states of startup and final states of shutoff phases has not been studied numerically. This paper aims to develop a coupled procedure for calculating the transient inlet flow rate as a part of the solution via application of the control volume method for linear momentum. Large eddy simulation of a four-blade axial hydraulic pump is carried out to calculate the forces at every time step. The sharp interface immersed boundary method is used to resolve the flow around the complex geometry of the propeller, stator and the pipe casing. The effect of the spurious pressure fluctuations, inherent in the sharp interface immersed boundary method, is damped by local time-averaging of the forces. The developed code is validated by comparing the steady-state volumetric flow rate with the experimental data provided by the pump manufacturer. The instantaneous and time-averaged flow fields are also studied to reveal the flow pattern and turbulence characteristics in the pump flow field.

The authors use control volume analysis for linear momentum to simulate the discharge rate as part of the solution in a large eddy simulation of an axial hydraulic pump. The linear momentum balance equation is used to update the inlet flow rate. The sharp interface immersed boundary method with dynamic Smagorinsky sub-grid stress model and a proper wall model is used.

The steady-state volumetric flow rate has been computed and validated by comparing to the flow rate specified by the manufacturer at the simulation conditions, which shows a promising result. The instantaneous and time averaged flow fields are also studied to reveal the flow pattern and turbulence characteristics in the pump flow field.

An approach is proposed for computing the volumetric flow rate as a coupled part of the flow solution, enabling the simulation of turbomachinery at all phases, including the startup/shutdown phase. To the best of the authors’ knowledge, this is the first large eddy simulation of a hydraulic pump to calculate the transient inlet flow rate as a part of the solution rather than specifying it as a fixed boundary condition. The method serves as a numerical framework for simulating problems incorporating complex shapes with moving/stationary parts at all regimes including the transient start-up and shut-down phases.

This paper aims to improve performance prediction and to acquire more detailed flow structures so as to analyze the turbulence in complex rotor-stator flow.

Hydraulic retarder as typical fluid machinery was numerically investigated by using hybrid Reynolds-averaged Navier–Stokes (RANS)/large eddy simulation (LES) models CIDDES Algebraic Wall-Modeled Large Eddy Simulation (LES) (WMLES) S-Ω and dynamic hybrid RANS/LES (DHRL). The prediction results were compared and analyzed with a RANS model shear stress transport (SST) k-omega which was a recommended choice in engineering.

The numerical results were verified by experiment and indicated that the predicted values for three hybrid turbulence models were more accurate. Then, the transient flow field was further analyzed visually in terms of turbulence statistics, Reynolds number, pressure-streamline, vortex structure and eddy viscosity ratio. The results indicated that HRL approaches could capture unsteady flow phenomena.

This study achieves both in performance prediction improvement and better flow mechanism understanding. The computational fluid dynamics (CFD) could be used instead of flow visualization to a certain extent. The improved CFD method, the fine computational grid and the reasonable simulation settings jointly enhance the application of CFD in the rotor-stator flow.

The improvement was quite encouraging compared with the reported literatures, contributing to the CFD playing a more important role in the flow machinery. DHRL provided the detailed explanation of flow transport between rotor and stator, which was not reported before. Through it, the flow mechanism can be better understood.

Purpose: The purpose of the chapter lies in identifying the challenges that female employees in the South African hospitality industry will face in the context of the economic impact of the COVID-19 lockdown.

Design: With this aim, we developed a questionnaire that has been filled by 101 hospitality professionals in order to explore the work security and perceived opportunities of people working in hospitality in South Africa.

Findings: Our findings confirm that South African women feel more uncertainty about their occupational future and are more afraid that they will not find a job within the tourism sector, even though it is one of the sectors where female employment is higher.

Research Limitations: The study was limited by the lack of literature regarding impact on gender disparities due to lockdown and the relative short period of time during which the data were collected. We recommend that future research should measure long-term effects of COVID-19 pandemic on this issue.

Practical/Social Implications: In order to alleviate the damage done by the post-COVID-19 lockdown on the South African tourist and hospitality industries policies addressing the accessibility of female workers to the job market need to be urgently developed and implemented.

Originality: Ours is the first research ever focussing on the gender inequalities in the tourism labour market in South Africa.