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This research aims to investigate how manufacturing flexibility can address the challenges of an ever-changing and unpredictable business environment in Bangladesh’s labor-intensive ready-made garment (RMG) industry, which is underserved and situated in a developing country.

Using Partial Least Square Structural Equation Modeling, this study empirically evaluated the relationships between manufacturing flexibility, environmental uncertainty and firm performance. The analysis utilized 320 survey responses from potential RMG experts, representing 95 organizations.

The study achieved a decision-making model for implementing manufacturing flexibility in the RMG industry of Bangladesh with acceptable model fit criterion. The research pinpointed that workforce flexibility plays the maximum mediating among different types of manufacturing in coping with demand and supply uncertainty in the RMG sector.

The study made valuable contributions to theoretical and practical knowledge in the context of manufacturing flexibility in Bangladesh’s RMG and other underserved labor-intensive sectors in developing economies. It suggests that managers should shift from defensive and risky business strategies to more aggressive and proactive approaches by utilizing workforce flexibility resources adaptively to enhance manufacturing capabilities and align with dynamic market demand. Additionally, the study offers recommendations for future research to build upon its findings.

This study is unique in its approach because it presents a decision model for implementing manufacturing flexibility in a labor-intensive industry in a developing economy, specifically the RMG industry in Bangladesh, whereas previous research has primarily focused on high-tech industries in developed economies.

A single-domain multi-phase model is developed for macrosegregation and shrinkage pipe formation in castings, as functions of buoyancy- and shrinkage-induced flow. The paper aims to discuss these issues.

Using a volume of fluid (VOF) method, both the air/liquid and air/solid interfaces are tracked during shrinkage pipe formation. A set of mixture advection-diffusion equations are derived and solved for velocity, temperature, composition, and phase field evolution. The fluid mechanics of the model are verified using a transient ditch drainage problem.

Results showing the interaction of macrosegregation and pipe formation are presented for two alloys under faster and slower cooling conditions.

This model provides a comprehensive tool to investigate relationships between the developing composition distribution and shrinkage pipe formation.

Since surface runoff clogs stormwater grates, leading to deterioration of drainage capacity, and also it is difficult to complete the study with actual dimensions in experiments, a numerical simulation work was established in this study to investigate the surface runoff clogging stormwater grate patterns. The purpose of this study is to describe the mechanisms of storm grate clogging and storm well deposition for different flow rate floods and granular materials.

In the work of this study, the volume of fluid (VOF) method and the discrete element method (DEM) are used to solve the gas–liquid and particle flows. In order to solve the evolution of the gas–liquid interface during surface runoff, the VOF was used. To simulate the rain grate and set up different material particles to represent the surface floating materials, the DEM was utilized.

The research results show that the clogging distribution and clogging rate of the rainwater grate are closely related to the fluid flow velocity and the physical characteristics of the particles, and the higher the clogging rate of the rainwater grate and the higher the number of particles deposited in the rainwater well at the same surface runoff velocity, the higher the density of the clogged particles. The surface runoff velocity (0.5 m/s, 1 m/s) shows that the rapid change of particle movement state at high runoff velocity makes the particle clogging more obvious.

A multi-scale CFD-DEM approach was used to simulate the particulate motion of the road surface with different incoming runoff velocities. The innovative use of DEM to model the storm grate simulation ensures the accuracy of the traction model.

The purpose of this paper is to experimentally and numerically investigate the interference characteristics between two ski-jump jets on the flip bucket in a large dam spillway when two floodgates are running.

The volume of fluid (VOF) method together with the Realizable k-ε turbulence model were used to predict the flow in two ski-jump jets and the free surface motion in a large dam spillway. The movements of the two gates were simulated using a dynamic mesh controlled by a User Defined Function (UDF). The simulations were run using the prototype dam as the field test to minimize errors due to scale effects. The simulation results are compared with field test observations.

The transient flow calculations, accurately predict the two gate discharges compared to field data with the predicted ski-jump jet interference flow pattern similar to the observed shapes. The transient simulations indicate that the main reason for the deflected nappe is the larger opening difference between the two gates as the buttress side gate closes. When both gates are running, the two ski-jump jets interfere in the flip bucket and raise the jet nappe to near the buttress to form a secondary flow on this jet nappe surface. As the gate continues to close, the nappe surface continues to rise and the surface secondary flow become stronger, which deflects the nappe over the side buttress.

A dynamic mesh is used to simulate the transient flow behavior of two prototype running gates. The transient flow simulation clarifies the hydraulics mechanism for how the two ski-jump jets interfere and deflect the nappe.

Heating with a low-frequency induction is a key phenomenon in a process dedicated to the treatment of nuclear wastes. This paper aims to present a step of the numerical model being developed to study this process.

A hydrodynamic model for the processing of a liquid charge consisting of a metallic phase and a dielectric one is developed based on a volume of fluid (VOF) approach coupled with electromagnetic calculations. The latter allows one to calculate the distribution of the Joule heating in the setup and radiative heat exchange inside the crucible is accounted with a surface-to-surface (S2S) model coupled with VOF.

Numerical results are compared with the measures obtained on the prototype of the process. The results are in good agreement but the model needs to be improved to consider the varying viscosity of the glass.

The usage of a S2S radiation model coupled to the VOF model is not common for studies of materials melted by electromagnetic induction. This paper demonstrates the feasibility of this approach.

The contact behaviors of droplets on confined surfaces influence significantly their dynamics and morphological transition induced by the electric field. This paper aims to delve into the electric stress, electric field distribution, flow field and evolution of droplet neck to understand the underlying mechanisms.

Electrohydrodynamics of droplets in confined environment is numerically analyzed based on finite volume method (FVM) combining with volume-of-fluid (VOF) method for two-phase interface capturing. Numerical solutions are obtained through solving electrohydrodynamics model coupling fluid dynamics with electrostatics.

It was found that the droplet neck with high interfacial curvature undergoes different transition depending on the contact angle. At large domain height, the droplets on the surfaces with the contact angle of θ < 90° tend to break up into smaller droplets adhered on top and bottom surfaces. The detachment of droplets is identified when the contact angle is much greater than 90°. Notably, the droplets at θ = 90° exhibit asymmetrical shape evolution, but for other cases there is symmetrical shape of droplets during transition process. With decreasing the domain height, no obvious deformation through driving the contraction of the droplet neck is observed.

It remains unclear how the electric field parallel to the surfaces affects the shape transition and electrohydrodynamics of confined droplets when changing the contact angle. In this paper, the authors study the electrohydrodynamics of droplets in confined space when the electric field is exerted parallel to contact surfaces. In particular, the authors consider the effect of the surface wettability on the droplet deformation. The problem is solved through FVM combining with the VOF method to implement the capturing of two-phase interfaces. The results indicate that the electrohydrodynamic behaviors of droplets are sensitive to the contact properties of droplets on the surfaces, which has not been reported in previous works.

An electrospinning process is a multi-phase and multi-physics process. The purpose of this paper is to numerically simulate the two-phase flow in the electrospinning process. The numerical results can offer in-depth insight into physical understanding of many complex phenomena which cannot be fully explained experimentally.

The two-phase flow can be calculated by solving the modified Navier-Stokes equations under the influence of electric field and the interface between the two fluids has been determined by using the Volume of Fluids (VOF) method. A realizable k-e model is used to model the turbulent viscosity. The numerical results can be obtained using Computational Fluid Dynamics (CFD) techniques.

The numerical simulation is a powerful tool to controlling over electrospinning parameters such as voltage, flow rate, and others.

The numerical simulation of two-phase flow model will take into account solvent evaporation and solidification of the jet, which play pivotal roles in determining the internal fiber morphology of the jet to be described here.

This paper deals with studying numerically the two-phase flow in the electrospinning process by applying CFD techniques. And the flow is modeled by ANSYS(FLUENT) using the VOF model.

The volume of fluid (VOF) method is a numerical technique to track the developing free surfaces of liquids in motion. This method can, for example, be applied to compute the liquid flow patterns in a rotating cone reactor. For this application a spherical coordinate system is most suited. The novel derivation of the extended VOF algorithms for this class of applications is presented here. Some practical limitations of this method, that are inherent in the geometry of the described system, are discussed.

The purpose of this paper is to investigate oil-gas slug formation in horizontal straight pipe and its associated pressure gradient, slug liquid holdup and slug frequency.

The abrupt change in gas/liquid velocities, which causes transition of flow patterns, was analyzed using incompressible volume of fluid method to capture the dynamic gas-liquid interface. The validity of present model and its methodology was validated using Baker’s flow regime chart for 3.15 inches diameter horizontal pipe and with existing experimental data to ensure its correctness.

The present paper proposes simplified correlations for liquid holdup and slug frequency by comparison with numerous existing models. The paper also identified correlations that can be used in operational oil and gas industry and several outlier models that may not be applicable.

The correlation may be limited to the range of material properties used in this paper.

Numerically derived liquid holdup and holdup frequency agreed reasonably with the experimentally derived correlations.

The models could be used to design pipeline and piping systems for oil and gas production.

The paper simulated all the seven flow regimes with superior results compared to existing methodology. New correlations derived numerically are compared to published experimental correlations to understand the difference between models.

Stir casting is a promising technique used for the manufacture of Al-SiC metal matrix composites. The clustering of reinforcement particles is a serious concern in this production method. In this work, mushy-state solidification characteristics in stir casting are numerically simulated using computational fluid dynamics techniques to study the clustering of reinforcement particles.

Effects of process parameters on the distribution of particles are examined by varying stirrer speed, volume fraction of reinforcement, number of blades on stirrer and diameter ratio (ratio of crucible diameter to stirrer diameter). Further, investigation of characteristics of cooling curves during solidification process is carried out. Volume of fluid method in conjunction with a solidification model is used to simulate the multi-phase fluid flow during the mushy-state solidification. Solidification patterns thus obtained clearly indicate a strong influence of process parameters on the distribution of reinforcement particles and solidification time.

From the simulation study, it is observed that increase in stirrer speed from 50 to 150 rad/s promotes faster solidification rate. But, beyond 100 rad/s, stirrer speed limit, clustering of reinforcement particles is observed. The clustering of reinforcement particles is seen when volume fraction of reinforcement is increased beyond 10 per cent. When number of blades on stirrer are increased from three to five, an increase in solidification rate is observed, and an uneven distribution of reinforcement particles are observed for five-blade geometry. It is also seen from the simulation study that a four-blade stirrer gives a better distribution of reinforcement in the molten metal. Decrease in diameter ratio from 2.5 to 1.5 promotes faster solidification rate.

There is 90 per cent closeness in results for simulation study and the published experimental results.