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This paper aims to improve the radial basis fuction mesh morphing method. During a shape optimization based on computational fluid dynamic (CFD) solvers, the mesh has to be changed. Two possible strategies are re-meshing or morphing. The morphing one is advantageous because it preserves the mesh connectivity, but it must be constrained.

RBF mesh deformation is one of the most robust and accurate morphing method. Using a greedy algorithm, the computational cost of the method is reduced. To evaluate the morphing performances, a rib shape optimization is performed using the NSGA-II algorithm coupled to kriging metamodels based on CFD. The morphing method is then compared to a re-meshing strategy.

The authors propose a method, based on Schur complement, to speed-up the greedy process. By using the information of the previous iteration, smaller linear systems are solved and time is saved. The optimization results highlight the interest of using a morphing-based metamodel regarding the resolution time and the accuracy of the interpolated solutions.

A new method based on Schur complement is addressed to speed-up the greedy algorithm and successfully applied to a shape optimization.

The choke flutter is a fluid-structure interaction that can lead to the failure of fan or compressor blade in turbojet engines. In ultra high bypass ratio (UHBR) fans, the choke flutter appears at part-speed regimes and at low or negative incidence when a strong shock-wave chokes the blade to blade channel. The purpose of this study is to locate the main excitation sources and improving the understanding of the different work exchange mechanisms. This work contributes to avoiding deficient and dangerous fan design.

In this paper, an UHBR fan is analyzed using a time-linearized Reynolds-averaged Navier–Stokes equation solver to investigate the choke flutter. The steady-state and the imposed vibration (inter blade phase angle, reduced frequency and mode shape) are selected to be in choke flutter situation. Superposition principle induced by the linearization allow to decompose the blade in numerous small subsections to track the contribution of each local vibration to the global damping. All simulations have been performed on a two-dimensional blade to blade extraction.

Result analysis points to a restricted number of excitation sources at the trailing edge which induce a large part of the work exchange in a limited region of the airfoil. Main phenomena suspected are the shock-wave motion and the shock-wave/boundary layer interaction.

An original excitation source tracking methodology allowed by the linearized calculation is addressed and applied to a UHBR fan test case.

Since capital is not evenly distributed across the world geography, each geography has different ways of life. Likewise, capitalism prevails within nation-states, which are the governorships of capital, and this is the main cause of inequalities. These inequalities lead to the consumption of a different industry in areas where industry or consumer culture cannot spread: The arms industry. For this, the conflict of elements with the necessary ethnic or sectarian distinctions is triggered and encouraged by the nation-state’s and corporations’ policies. The state, as the governorship of capitalism and the companies behind it, supports the consumption of the products of the arms industry, one of the most important economic factors of capitalism, precisely in these areas. Conflicts between armies and so-called “terrorist” groups are very convenient and functional points for the arms industry to find new markets. In this study, the reality of “stone-throwing children,” which is a part of the Kurdish people’s struggle for existence, has been going on in various grammars for nearly a hundred years, and the representation of this reality in mainstream newspapers in Turkey will be shown. The Diyarbakır branch of the Human Rights Association of Turkey and 11 non-governmental organizations have reported that between 2006 and 2010, 4,000 children between the ages of 12 and 18 were detained or imprisoned for periods ranging from 2 months to 4 years. The findings of academic articles on the representation of stone-throwing children in the media will be summarized.