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Based on a lumped mass model and an incremental iteration method, an efficient simultaneous iteration procedure is developed for the finite element solution of the enthalpy model. This procedure uses Gauss elimination to solve the resulting algebraic equation system. A one‐point quadrature program based on the isoparametric quadrilateral element is incorporated for the calculation of the heat conductance matrix, leading to a significant reduction of the computation time.

The purpose of this study is to investigate the coherent structures of pulsed opposing jets by large eddy simulation (LES) model and proper orthogonal decomposition (POD) snapshot method. Flow pulsation as an active flow control method is considered for the enhancement of transport phenomena in impinging jets. The effect of flow pulsation parameters such as pulsation signal shape and frequency on the vortical coherent structures, the energy content of primary modes and their variation are studied numerically.

In this study, flow field of turbulent pulsating opposing jets has been simulated using LES. The result of the simulation in different time steps (snapshots) are stored and POD is applied on the snapshots. In this study, the POD method and calculation of spatial modes has been done using OpenFOAM, and time coefficients have been calculated using a MATLAB code.

The results of this study show that the flow excitation has a great effect on the coherent structure formation and the energy containment of fundamental modes of the flow. When the flow was excited by a harmonic sinusoidal or step function, the turbulent kinetic energy accumulated in the set of primary modes. On the other hand, the pulsed opposing jets had more regularity compared to the steady jets. The shapes, patterns and energy values of dominant modes depended on the inlet pulsation signal. An increase in pulsation frequency leads to an augmentation in energy content of the primary modes.

The predictions may be extended to include various pulsation conditions such as: various amplitudes, Reynolds number and aspect ratio.

The results of this study are a valuable source of information for active control of transport phenomena in opposing jet configurations which is used in different industrial applications such as cooling, combustion, reactors, heating and drying processes.

In this study, the coherent structures and energy content of primary modes was studied for the first time by LES model and POD snapshot method and a comprehensive discussion on numerical results is provided.

In the original effective heat capacity method the latent heat effect is approximated by a large effective heat capacity over a small temperature range. This method is simple in concept and easy to implement. However, it is so sensitive to the choice of the phase change temperature interval and the chosen time integration scheme that non‐convergence always occurs when it is implemented with implicit time integration schemes. Presents the cause and cure of non‐convergence in effective heat capacity methods and discusses sample results.

This paper presents a two‐dimensional finite element model for convection‐dominated melting and freezing problems. The enthalpy‐porosity approach is utilized to account for the physics of the evolution of the melt velocity at the solid/liquid phase change interface. Penalty formulation is employed to treat the incompressibility constraint in the momentum equations. The streamline upwind/Petrov Galerkin method is used in combination with primitive variables to solve the governing equations. Simulations are carried out for melting of a pure phase change material in a rectangular cavity heated from below. Sample results are presented and discussed.

The purpose of this paper is to examine entropy generation rate in the flow and temperature field due pulsed impinging jet on to a flat plate. Heat transfer of pulsed impinging jets has been investigated by many researchers. Entropy generation is one of the parameters related to the second law of thermodynamics which must be analyzed in processes with heat transfer and fluid flow in order to design efficient systems. Effect of velocity profile parameters and various nozzle to plate distances on viscous and thermal entropy generation are investigated.

In this study, the flow and temperature field of a pulsed turbulent impinging jet are simulated numerically by the finite volume method with appropriate boundary conditions. Then, flow and temperature results are used to calculate the rate of entropy generation due to heat transfer and viscous dissipation.

Results show that maximum viscous and thermal entropy generation occurs in the lowest nozzle to plate distance and entropy generation decreases as the nozzle to plate distance increases. Entropy generation in the two early phase of a period in the most frequencies is more than steady state whereas a completely opposite behavior happens in the two latter phase. Increase in the pulsation frequency and amplitude leads to enhancement in entropy generation because of larger temperature and velocity gradients. This phenomenon appears second and even third peaks in entropy generation plots in higher pulsation frequency and amplitude.

The predictions may be extended to include various pulsation signal shape, multiple jet configuration, the radiation effect and phase difference between jets.

The results of this paper are a valuable source of information for active control of transport phenomena in impinging jet configurations which is used in different industrial applications such as cooling, heating and drying processes.

In this paper the entropy generation of pulsed impinging jet was studied for the first time and a comprehensive discussion on numerical results is provided.

Three-dimensional (3D) food printing is an innovative technology used to customize food products through the integration of digital technology and food ingredients. The purpose of this study is to assess the current state of research in the field of 3D food printing, identify trending topics and identify promising future research directions.

This bibliometric review systematically evaluates the field of 3D food printing using data from published literature in the Web of Science database. After reference screening, 812 articles were included in the analysis.

The result reveals that research in 3D food printing primarily focuses on the optimization and characterization of mechanical and rheological properties of food inks and that post-printing processing, such as laser treatment, has emerged recently as an important consideration in 3D food printing. However, extant works lack animal and human studies that demonstrate the functionality of 3D-printed food.

This sophisticated bibliometric analysis uncovered the most studied current research topics and the leading figures in the area of 3D food printing, providing promising future research directions.

This study aims to comprehensively analyse the implementation and effectiveness of corporate social responsibility (CSR) policies within the context of the Indian coal mining sector. Furthermore, it investigates the alignment between CSR initiatives and the unique challenges faced by the coal mining sector and examines the outcomes and impacts of these initiatives on the employees of the sector and their perspective on the situation.

This study adopts a comprehensive qualitative research method, including a review of the literature, case studies and stakeholder interviews. This study seeks to deconstruct the application of CSR policies.

The analysis developed a deeper understanding of the complexities surrounding CSR policies in the Indian coal mining sector, offering insights into strategies for enhancing the effectiveness and relevance of these initiatives while fostering sustainable development.

This study reveals a rich tapestry of theoretical implications and how they connect to important organisational and societal paradigms. The results of this qualitative analysis can work as a foundation for creating scales to measure the level of efficiency of CSR policies implemented by different companies. Furthermore, this study goes beyond theoretical knowledge and gives companies, regulators and communities information they can use. By looking at how CSR policies work in the real world, a road map for responsible resource extraction and community growth can be made.

The findings are unique in exploring the CSR initiatives and the unique challenges faced by the coal mining sector. This study offers insight on the employees of the sector and their perspectives on the situation and delves into the multifaceted dimensions of CSR practices.

Many a times, the information about the boundary heat flux is obtained only through inverse approach by locating the thermocouple or temperature sensor in accessible boundary. Most of the work reported in literature for the estimation of unknown parameters is based on heat conduction model. Inverse approach using conjugate heat transfer is found inadequate in literature. Therefore, the purpose of the paper is to develop a 3D conjugate heat transfer model without model reduction for the estimation of heat flux and heat transfer coefficient from the measured temperatures.

A 3 D conjugate fin heat transfer model is solved using commercial software for the known boundary conditions. Navier–Stokes equation is solved to obtain the necessary temperature distribution of the fin. Later, the complete model is replaced with neural network to expedite the computations of the forward problem. For the inverse approach, genetic algorithm (GA) and particle swarm optimization (PSO) are applied to estimate the unknown parameters. Eventually, a hybrid algorithm is proposed by combining PSO with Broyden–Fletcher–Goldfarb–Shanno (BFGS) method that outperforms GA and PSO.

The authors demonstrate that the evolutionary algorithms can be used to obtain accurate results from simulated measurements. Efficacy of the hybrid algorithm is established using real time measurements. The hybrid algorithm (PSO-BFGS) is more efficient in the estimation of unknown parameters for experimentally measured temperature data compared to GA and PSO algorithms.

Surrogate model using ANN based on computational fluid dynamics simulations and in-house steady state fin experiments to estimate the heat flux and heat transfer coefficient separately using GA, PSO and PSO-BFGS.

This study aims to develop nutritious and functional gluten-free cakes for celiac patients by substituting rice flour with unripe banana peel flour (UBPF) (0%, 5%, 10%, 15% and 20%) and to propound some chemical, textural and sensorial properties of cakes. A secondary purpose was also to contribute to waste management of the banana products industry by reevaluating the peel.

One-way analysis of variance and Duncan’s multiple comparison test (p < 0.05) were used to determine differences among the mean values. Proximate analysis, color, texture profile analysis, antioxidant activity, mineral composition and sensorial analysis were carried out. Data was analyzed using SAS software. Cake production was carried out in three replications.

UBPF in this study had high protein (11.2%) and dietary fiber (18.3%) as well as high antioxidant activity. In all, 5%–20% UBPF-substituted cakes had enhanced dietary fiber (2.5%–3.7% dry matter), ash content (1.6%–1.9% DM) in comparison to control cake (1.4% and 1.4%, respectively). 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of enriched gluten-free cakes increased by 102%–534%, whereas ferric-reducing antioxidant power increased by 29.6%–143%. Up to 10% UBPF substitution resulted in texturally and sensorially acceptable, nutritious gluten-free cakes.

The developed product can be used practically for several applications as a healthy alternative. The use of unripe banana peel represents a promising strategy to increase the nutritional value and number of ready-to-eat food in the gluten-free market.

This study propounds a nutritious, functional and sensorially acceptable gluten-free cake for celiac people to use practically while socialization. Cakes which are appreciated by panelists in sensory analysis will create product variety in kitchens, markets and social areas, in particular for those people suffering from celiac and gluten intolerance.

This is the first study to consider UBPF as an ingredient in gluten-free cake formulation. The product may positively contribute to the life quality of celiac people by propounding a gluten-free snack food for consumption in their social life. This study is also an example of the contribution of banana by-products toward the implementation of the circular economy.