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Maintaining the turbine blade’s temperature within the safety limit is challenging in high-pressure turbines. This paper aims to numerically present the conjugate heat transfer analysis of a novel approach to mini-channel embedded film-cooled flat plate.

Numerical simulations were performed at a steady state using SST k – ω turbulence model. Impingement and film cooling are classical approaches generally adopted for turbine blade analysis. The existing film cooling techniques were compared with the proposed design, where a mini-channel was constructed inside the solid plate. The impact of the blowing ratio (M), Biot number (Bi) and temperature ratio (TR) on overall cooling performance was also studied.

Overall cooling effectiveness was always shown to be higher for mini-channel embedded film-cooled plates. The effectiveness increases with increasing the blowing ratio from M = 0.3 to 0.7, then decreases with increasing blowing ratio (M = 1 and 1.4) due to lift-off conditions. The mini-channel embedded plate resulted in an approximately 21% increase in area-weighted average overall effectiveness at a blowing ratio of 0.7 and Bi = 1.605. The lower uniform temperature was also found for all blowing ratios at a low Biot number, where conduction heat transfer significantly impacts total cooling effectiveness.

To the best of the authors’ knowledge, this study presents a novel approach to improve the cooling performances of a film-cooled flat plate with better cooling uniformity by using embedded mini-channels. Despite the widespread application of microchannels and mini-channels in thermal and fluid flow analysis, the application of mini-channels for blade cooling is not explored in detail.

This study aims to enhance natural convection heat transfer for a porous thermal cavity. Multi-frequency sinusoidal heating is applied at the bottom of a porous square cavity, considering top wall adiabatic and cooling through the sidewalls. The different frequencies, amplitudes and phase angles of sinusoidal heating are investigated to understand their major impacts on the heat transfer characteristics.

The finite volume method is used to solve the governing equations in a two-dimensional cavity, considering incompressible laminar flow, Boussinesq approximation and Brinkman–Forchheimer–Darcy model. The mean-temperature constraint is applied for enhancement analysis.

The multi-frequency heating can markedly enhance natural convection heat transfer even in the presence of porous medium (enhancement up to ∼74 per cent). Only the positive phase angle offers heat transfer enhancement consistently in all frequencies (studied).

The present research idea can usefully be extended to other multi-physical areas (nanofluids, magneto-hydrodynamics, etc.).

The findings are useful for devices working on natural convection.

The enhancement using multi-frequency heating is estimated under different parametric conditions. The effect of different frequencies of sinusoidal heating, along with the uniform heating, is collectively discussed from the fundamental point of view using the average and local Nusselt number, thermal and hydrodynamic boundary layers and heatlines.

Supplier selection for capital procurement is a major strategic decision for any automobile company. The decision determines the success of the company and must be taken systematically with the utmost transparency. The purpose of this paper is to construct capital procurement decision-making model to optimize supplier selection in the Indian automobile industry.

To achieve the stated objective, a combined approach of fuzzy theory and AHP-DEMATEL is applied. Evaluation parameters are identified through an extensive literature review and criteria validation has been introduced through a Fuzzy Delphi method by using fuzzy linguistic scales to handle the vagueness of information. AHP is employed to find the priority weight of criteria, although an inter-relationship map among criteria is not possible through AHP alone since it considers all criteria as independent. To overcome this, DEMATEL is used to establish cause-effect relationships among criteria.

The results show that the total cost of ownership (TOC) is the first weighted criterion in supplier selection for capital procurement, followed by manufacturing flexibility and maintainability, then conformity with requirement. The cause-effect model shows that supplier profile, TOC, service support and conformity with requirement are in the cause group and are considered to be the most critical factors in selecting the supplier.

The study’s outcome can help the automobile industry to optimize their selection process in selecting their suppliers for capital procurement; the proposed model can provide guidelines and direction in this regard.

The current study aims to address the interaction between participating media radiation with thermo-gravitational convection of an electrically conducting fluid enclosed within a tilted enclosure under an externally imposed time-independent uniform magnetic field.

The differentially heated boundaries of the tilted enclosure are considered to be diffuse, gray and the enclosed fluid is assumed to be absorbing, emitting and isotropically scattering. The Navier-Stokes equations, meant for magneto convection are solved using modified MAC method. Gradient dependent consistent hybrid upwind scheme of second order is used for discretization of the convective terms. Discrete ordinate method, with S8 approximation, is used to model radiative transport equation in the presence of radiatively active medium.

Effect of uniform magnetic field with different magnitudes and orientations of cavity has been numerically simulated. The effect of participating media radiation has been investigated for different optical thicknesses, emissivities, scattering albedos and Planks number. The results are provided in both graphical and tabular forms. The flow lines, isotherms bring clarity in the understanding of flow behaviour and heat transfer characteristics.

Despite the idealized nature, the present study is quite essential to understand the cumbersome physics of realistic problem.

The purpose of this paper is to describe the development of a scale for the evaluation of the perceived quality of services provided to students with disabilities by Special Vocational Education (SVE) institutions in Greece.

SVE service quality was approached on the basis of the performance-only model. The participatory research paradigm was followed, engaging students with disability and specifically with intellectual disability in several stages of the instrument development. The methodological design included two phases for the establishment and testing of the reliability and validity of the scale.

The findings of the study support a multifactorial construct of SVE service quality consisting of five factors: responsiveness, surroundings, personalization, training and facilities adequacy.

Generalization of results should be attempted with concern. The type and severity of disability should be considered in future use of the scale. The construct of training for students with disability needs to be further investigated.

SVE-Service-Quality Scale may be used in SVE settings highlighting areas of improvement or as an instrument for the assessment of implemented interventions.

Participatory research may serve as an empowerment opportunity for students with disability, whose active engagement in the research design allows for a small-scale yet valuable social impact, promoting emancipation for people with disability.

The study draws attention on the field of SVE service quality where research is scarce, introducing SVE in the discussion about educational service quality assessment.

This paper aims to investigate how relative contractual and relational governances impact seller’s value appropriation via buyer’s trust, perceived justice and opportunism in the context of industrial buyer–seller relationships.

Survey data from 232 matched buyer-seller dyads of Chinese business-to-business (B2B) firms was used to test the conceptual model and research hypotheses. The confirmatory factor model and structural equation model were tested by using Lisrel 8.80.

The findings show that relative contractual governance and relative relational governance have opposite consequences on B2B relationship and value outcomes. Relative contractual governance generates higher level of buyer’s opportunist behavior because it reduces buyer’s trust and perceived justice, therefore harms seller’s value appropriation. By contrast, relative relational governance enhances buyer’s trust and perceived justice, therefore curbs buyer’s opportunism and improves seller’s value appropriation.

This study makes significant contributions to theory development of value appropriation and inter-firm governance mechanism by extending dyadic view to network view. It proposes the concept of relative governance and explores its role in shaping a business partner’s perception and behavior. It also provides insightful implications for B2B companies on capturing more benefits from the relationship with buyers by leveraging relative governance strategies.

The purpose of this paper is to appraise the impact of mobile shopping platform characteristics on consumer’s emotions, the relationship between emotions and their impact on impulsive buying.

Mobile shopping platform characteristics were grouped into five dimensions: information, entertainment, personalization, visuality and economic benefits, and integrated in a model built on the Stimulus-organism-response theory to evaluate the influence on arousal (excitement) and pleasure, the relationship between arousal and pleasure and their impact on impulsive buying. In total, 303 valid questionnaires were collected from Chinese mobile shoppers. The research hypotheses were tested through confirmatory factor analysis and structural equation modeling.

Entertainment and personalization had significant positive influences on consumer’s arousal and pleasure. Information, visuality and economic benefits had significant positive influences on consumer’s arousal. Arousal had a significant positive impact on consumer’s pleasure. Arousal and pleasure had significant positive influences on impulsive buying.

New insights can be obtained by investigating other consumer’s profiles. The model can be improved by including other mobile platform characteristics (product availability, platform ease-of-use and interactivity) and broadening the impulsive buying perspective through assessing flow experience and virtual atmosphere.

Marketing strategies are proposed based on the mobile platform characteristics and considering Chinese customer values, for generating positive emotions and impulsive buying.

This study enriches the literature by recommending a classification for mobile shopping platform characteristics and proposing a model to investigate the characteristics, emotions and impulsive buying nexus.

The solution of radiative heat transfer problems in participating media is often obtained using the standard discrete ordinates method (SDOM). This method produces anomalies caused by ray effects if radiative boundary conditions have discontinuities or abrupt changes. Ray effects may be mitigated using the modified discrete ordinates method (MDOM), which is based on superposition of the solutions obtained by considering separately radiation from the walls and radiation from the medium. The purpose of this paper is to study the role of ray effects in combined conduction‐radiation problems and investigate the superiority of the MDOM over SDOM.

The MDOM has been used to calculate radiative heat transfer in irregular geometries using body‐fitted coordinates. Here, the blocked‐off region concept, originally developed in computational fluid dynamics, is used along with the finite volume method and SDOM or MDOM to solve combined conduction‐radiation heat transport problems in irregular geometries. Enclosures with an absorbing, emitting and isotropically or anisotropically scattering medium are analyzed.

The results confirm the capability of the MDOM to minimize the anomalies due to ray effects in combined heat transfer problems, and demonstrate that MDOM is more computationally efficient than SDOM.

The paper demonstrates the application of MDOM to combined conduction‐radiation heat transfer problems in irregular geometries using blocked‐off method.