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In the aeronautical industry, the pursuit of efficiency is a fundamental factor that governs the characteristics of an aircraft. Therefore, the implementation of new aerodynamic devices capable of altering the airflow behavior is a highly significant advancement in the field. One theoretical proposal dedicated to optimizing the aerodynamic efficiency of a wing involves the use of a non-planar "C"-shaped design. By doing so, a significant portion of the aerodynamic resistance produced by wingtip vortices can be drastically reduced while maintaining total lift. In this study, building upon previous research primarily based on inviscid potential flow methods (such as the Discrete Vortex Method or the Vortex Lattice Method), the airflow behavior through a C-wing will be investigated. To this end, a previously designed and analyzed wing configuration will be studied using the Finite Volume Method, which takes into account the effects of viscosity and provides more accurate results. Furthermore, the airflow behavior through the C-wing will be compared to that of an equivalent conventional wing. For this purpose, an open-source computational fluid dynamics program and the Reynolds-averaged Navier-Stokes equations will be employed.

While striving for a circular economy of metals, the Flash Smelting Furnace (FSF) is the most common and “green” aggregate for primary smelting of copper concentrates, because of already today low CO2-emissions compared to other smelting technologies. High dust carry-over often leads to problems with flue dust accretions in its subsequent cooling aggregate, the Waste Heat Boiler (WHB). Removing these accretions causes mechanical stress for the boiler tubes and can lead to extended downtime and maintenance. The WHB has a limited accessibility towards experimental studies because of its harsh process conditions. Hence, Computational Fluid Dynamics (CFD) models appear as convenient option for WHB studies and design, but are not used for the evaluation of flue dust accretions yet. For the inclusion of this feature into a three-dimensional CFD model of the entire WHB, a new sticking function is developed. It is based on the industrial experience that flue dust is only sticky above a certain softening temperature. Since the WHB has a varying dust input due to the flexible operation of the FSF, a parameter study is conducted for standard flue dust, pure copper oxide dust and pure iron oxide dust, finding minor sensitivity towards the flue dust density and no sensitivity towards the dust heat capacity. From these findings, recommendations for the minimization of flue dust accretion formation in the WHB are derived.

In the present paper, three-dimensional Fluid structures and wake characteristics are evaluated for a square cylinder with an upstream splitter plate. The splitter plate divides the incoming flow in two streams, the upper and lower one, existing between them a velocity ratio. Two different Reynolds numbers of 56 and 200 and three different velocity ratios are here considered. The effect of the mixing enhancement using a square cylinder located downstream of the splitter plate is evaluated. A Floquet analysis to compute the spanwise wavelengths of three dimensional disturbances appearing in the square cylinder wake with and without a splitter plate is performed. It is observed that the use of the detached splitter plate has a stabilizing effect at low velocity ratios. However, when the velocity ratio increases, the vortex shedding suffers a linear increase and the wake resembles that of a mixing layer. Vortex dislocations appear at ratios larger than 2, which points out the onset of a bifurcation to a more chaotic wake. The wavelength of this secondary instability has been measured by means of Floquet analysis and two-point correlations being in the order of 3.5D., Peer Reviewed, Postprint (published version)

Design and optimization of trawl-doors are key factors in minimizing the fuel consumption of fishing vessels. This paper discusses optimization of the trawl-door shapes using high-fidelity 3D computational fluid dynamic (CFD) models. The accurate 3D CFD models are computationally expensive and, therefore, the direct use of traditional optimization algorithms, which often require a large number of evaluations, may be prohibitive. The design approach presented here is a variation of sequential approximate optimization exploiting low-order local response surface models of the expensive 3D CFD simulations. The algorithm is applied to the design of modern and airfoil-shaped trawl-doors., QC 20220420