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This investigation aims to analyze the steel-flux interface level fluctuation because of electromagnetic stirring and its process parameters in a continuous casting billet mold.

An un-coupled numerical model for electromagnetic field generation and a coupled numerical model of electromagnetic field and two-phase fluid flow have been developed. The two-phase fluid flow has been modeled using volume of fluid method, in which externally generated time-varying electromagnetic field is coupled and analyzed using magnetohydrodynamic method. Top surface standing wave stability criteria are used to study the criticality of interface stability.

Results show that application electromagnetic field for stirring increases the interface level fluctuation, specifically at the mold corners and near the submerged entry nozzle. The increase in current intensity and stirrer width barely affect the interface level. However, interface level fluctuation increases considerably with increase in frequency. Using stability criteria, it is found that at 20 Hz frequency, the ratio of height to wavelength of interface wave increases much above the critical value. The iso-surface of the interface level shows that at 20 Hz frequency, mold flux gets entrapped into the liquid steel.

The model may be used during optimization of in-mold electromagnetic stirrer to avoid mold flux entrapment and control the cast quality.

The study of mold level fluctuation in the presence of in-mold electromagnetic stirrer has rarely been reported. The criticality of stirrer process parameters on level fluctuation has not been yet reported. This study lacks in experimental validation; however, the findings will be much useful for the steelmakers to reduce the casting defects.

To effectively control the molten steel flow and the stability of free surface in continuous casting mould, this paper aims to propose a new type electromagnetic brake technique, namely, vertical electromagnetic brake (V-EMBr). Its brake effect under special processing parameters such as submerged entry nozzle (SEN) depth and port angle is evaluated by the numerical simulation methods.

A couple three-dimensional mathematical model of fluid flow and static magnetic field was developed to investigate the behaviour of molten steel flow and steel/slag interface in the continuous casting mould, and a volume of fluid model is used to track the interfacial behaviour of molten steel and liquid slag by solving the continuity equation of the phase volume fraction.

The simulation results showed that the application of V-EMBr can significantly reduce the flow intensity in upper recirculation zone and decrease the meniscus height and the flow velocity of molten steel in the vicinity of narrow side of mould, which is beneficial to reduce the possibility of mould flux entrapment. Especially, the brake effect of V-EMBr has a little affected by the SEN depth and port angle, which is helpful for V-EMBr to better adapt the actual continuous casting process.

Compared to the conventional-level EMBr, the new proposed V-EMBr has the advantage to effectively control the molten steel flow and steel/slag interfacial fluctuation in the vicinity of narrow side of mould with a pair of magnetic fields, and its brake effect is less affected by the changes in continuous casting processing parameters.

Two‐dimensional numerical simulations have been performed using a finite volume method that employs unstructured grids with cell‐wise local refinement and an interface‐capturing scheme to predict the shape of the free surface, thus simulating the surface wave that is created in a mold due to the flow from the submerged entry nozzle (SEN). Simulation has been done for 1:6.25 aspect ratio of the mold having a height of 2 m with parallel rectangular ports as well as 15° upward and downward ports. It has been found that for low inlet velocity of the SEN (<1 m/s) the maximum wave amplitude of the surface remains below 12 mm and no outside air is entrapped by the wave to form a bubble. However, for high inlet velocity (2 m/s or more) there is considerable fluctuations on the free surface and the maximum wave amplitude shoot up beyond 70 mm at the start up and slowly falls to about 30 mm entrapping air bubbles from the surroundings. The movement of the air bubble within the mold and its rise to the free surface where it subsequently collapses has been captured well in the numerical simulation. The overall shape of the free surface matches well, excepting the initial transience, with that of the experimentally observed free surface, although the free surface never attains a perfect steady shape neither in the experiment nor in the numerical simulation due to its continuous oscillation and breaking.

The purpose of this article is to numerically investigate the effect of casting speed on the fluid flow, solidification and inclusion motion under the influence of electromagnetic stirring (EMS) in the bloom caster mold with bifurcated submerged entry nozzle (SEN).

The electromagnetic field obtained by solving Maxwell’s equation is coupled with the fluid flow, solidification and discrete phase model using the in-house user-defined functions. An enthalpy porosity approach and Lagrangian approach are applied for the solidification analysis and non-metallic inclusions motion tracking, respectively.

Investigation shows that the casting speed and EMS significantly affect the steel flow, solidification and inclusion behavior inside the mold. Investigations are being conducted into the complex interplay between the induced flow and the SEN’s inertial impinging jet. In low and medium casting speeds, the application of EMS significantly increases the inclusion removal rate. Inclusion removal is studied for its different size and density and further effect of EMS is also reported on cluster formation and distribution of inclusion in the domain.

The model may be used to optimize the process parameter (casting speed and EMS) to improve the casting quality of steel by removing the impurities.

The effect of casting speed on the solidification and inclusion behavior under the influence of time-varying EMS in bloom caster mold with bifurcated nozzle has not been investigated yet. The findings may assist the steelmakers in improving the casting quality.

Investigates conservation problems facing cultural collections in libraries and museums. Provides recommended levels of environmental control and a suggested risk assessment of collections. Concludes that conserving items may not be possible for small museums.

The purpose of this paper is to develop a decision support tool to use with design for additive manufacturing (DfAM) and design for supply chain (DfSC) such that the Supply Chain (SC) configuration for a personalized product can be optimized under various demand uncertainties.

A simulation-based methodology is proposed in this industry-university cooperative research. Through identifying the company requirements with interview, an application programming interface (API) and simulation model were developed to solve the DfAM and DfSC problems of case company. Based on customer preference, the SC configuration is analyzed and suggestions are developed according to simulation results at the product design.

Results show the supplementary capacity of the additive manufacturing (AM) process improves the SC performance in terms of lead time and total cost. This work identifies the research gap between AM and SC, and gives a comprehensive investigation of different performance indicators, such as order fulfill rate and waste rate.

Metal AM technology was not in the mass production stage at the time of this study. Thus, this research mainly emphasizes a nonmetal AM process.

AM technology can improve SC performance through its supplementary capacity and help the SC to be more flexible, robust and resilient in terms of lead time and total cost. This research implements an API to assist decision making. The findings of this research provide case company a valuable reference while branching its business.

This is the first study that considers both DfAM and DfSC with the integration of an API. It also addresses the demand fluctuation level and stochastic demand of a personalized product in a unique approach.

The purpose of this paper is to develop a novel unstructured simulation approach for injection molding processes described by the Hele‐Shaw model.

The scheme involves dual dynamic meshes with active and inactive cells determined from an initial background pointset. The quasi‐static pressure solution in each timestep for this evolving unstructured mesh system is approximated using a control volume finite element method formulation coupled to a corresponding modified volume of fluid method. The flow is considered to be isothermal and non‐Newtonian.

Supporting numerical tests and performance studies for polystyrene described by Carreau, Cross, Ellis and Power‐law fluid models are conducted. Results for the present method are shown to be comparable to those from other methods for both Newtonian fluid and polystyrene fluid injected in different mold geometries.

With respect to the methodology, the background pointset infers a mesh that is dynamically reconstructed here, and there are a number of efficiency issues and improvements that would be relevant to industrial applications. For instance, one can use the pointset to construct special bases and invoke a so‐called “meshless” scheme using the basis. This would require some interesting strategies to deal with the dynamic point enrichment of the moving front that could benefit from the present front treatment strategy. There are also issues related to mass conservation and fill‐time errors that might be addressed by introducing suitable projections. The general question of “rate of convergence” of these schemes requires analysis. Numerical results here suggest first‐order accuracy and are consistent with the approximations made, but theoretical results are not available yet for these methods.

This novel unstructured simulation approach involves dual meshes with active and inactive cells determined from an initial background pointset: local active dual patches are constructed “on‐the‐fly” for each “active point” to form a dynamic virtual mesh of active elements that evolves with the moving interface.

Only continuously monitoring cavity pressure allows the detailed recording of the injection molding process in the injection, compression and holding pressure phases. It alone correlates with all significant molding features such as weight, morphology, degree of forming, burr formation, shrink marks and cavities as well as shrinkage and deformation. The cavity pressure not only optimizes the timing of the switching point from the compression to the holding pressure phase, but also serves directly as a criterion for the switching. Molding weights and countless other quality characteristics thereby vary considerably less than with switching based on hydraulic pressure, screw travel or time. Quartz sensors have proved particularly successful for direct and indirect measurement of pressure. Advocates the use of cavity pressure sensors for monitoring and control of the injection molding process and describes commercial products that are available.

Millions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the effect of insulating such floors. Upgrading floors changes the void conditions, which might increase or decrease moisture build-up and mould and fungal growth. The purpose of this paper is to provide a review of the current global evidence and present the results of in situ monitoring of 15 UK floor voids.

An extensive literature review on the moisture behaviour in both uninsulated and insulated suspended timber crawl spaces is supplemented with primary data of a monitoring campaign during different periods between 2012 and 2015. Air temperature and relative humidity sensors were placed in different floor void locations. Where possible, crawl spaces were visually inspected.

Comparison of void conditions to mould growth thresholds highlights that a large number of monitored floor voids might exceed the critical ranges for mould growth, leading to potential occupant health impacts if mould spores transfer into living spaces above. A direct comparison could not be made between insulated and uninsulated floors in the sample due to non-random sampling and because the insulated floors included historically damp floors. The study also highlighted that long-term monitoring over all seasons and high-resolution monitoring and inspection are required; conditions in one location are not representative of conditions in other locations.

This study presents the largest UK sample of monitored floors, evaluated using a review of current evidence and comparison with literature thresholds.