SUMMARYThis paper outlines the development and adaptation of a coupling strategy for transient temperature analysis in a solid via a conjugate heat transfer method. This study proposes a quasi‐dynamic coupling procedure to bridge the temporal disparities between the fluid and the solid. In this approach, dynamic thermal modeling in the solid is coupled with a sequence of steady states in the fluid. This quasi‐dynamic algorithm has been applied to the problem of convective heat transfer over, and transient conduction heat transfer within, a flat plate using the severe thermal conditions of a solid propellant rocket. Two different coupled thermal computations have been performed. In the first one—referred to as the reference computation—the coupling period is equal to the smallest solid time constant. In the second one, a very large coupling period is used. The results show that the procedure can predict accurate transient temperature fields at a reasonable computational cost. The simulation CPU time is approximately reduced by up to 90%, while maintaining a very good accuracy. All the details of the numerical test case are given in the paper. This application illustrates the capabilities and the overall efficiency of this coupled approach in a solid transient problem using long term simulations of time dependent flows. Copyright © 2013 John Wiley & Sons, Ltd.

Two models have been implemented for calculating the thermal radiation emitted at the ingot top in the VAR process, namely a crude model that considers only radiative heat transfer between the free surface and electrode tip and a more detailed model that describes all radiative exchanges between the ingot, electrode and crucible wall using a radiosity method.From the results of the second model, it is found that the radiative heat flux at the ingot top may depend heavily on the arc gap length and the electrode radius, but remains almost unaffected by variations of the electrode height. Both radiation models have been integrated into a CFD numerical code that simulates the growth and solidification of a VAR ingot. The simulation of a Ti-6-4 alloy melt shows that use of the detailed radiation model leads to some significant modification of the simulation results as compared to the simple model. This is especially true during the hot-topping phase, where the top radiation plays an increasingly important role as compared to the arc energy input. Thus, whereas the crude model has the advantage of its simplicity, use of the detailed model should be preferred.

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Quels sont les nouveaux modèles des industries culturelles ? Pour contribuer à la réponse, nous étudions un cas qui s’avère à la fois singulier et révélateur d’une nouvelle organisation de la production artistique. Dans une démarche ethnographique, nous construisons notre contribution sur une étude de cas intrinsèque. L’entreprise c.H-D art production est spécialisée dans la mise en œuvre de techniques innovantes associées à des savoir-faire de construction pour la réalisation d’œuvres dites monumentales. L’étude de ce cas nous permet de repérer l’émergence de nouvelles formes de collaboration et de nouveaux modes de production dans le contexte particulier des arts plastiques.