This paper develops the unsteady continuous adjoint method for aeroacoustic problems governed by time-dependent turbulent flows. To predict flow-induced sound radiation from a body in free-stream, an incompressible Improved Delayed Detached Eddy Simulation is firstly performed. The generated noise is then

This paper presents an approach which increases the flexibility of a computer-aided design (CAD) model by automatically refining its parameterization and adding new CAD features to the model´s feature tree. It aims to overcome the limitations imposed by the choice of parameters used during the initial model creation, which constrains how the model shape can change during design optimization. Parametric Effectiveness compares the maximum performance improvement that can be achieved using a parameterization strategy, to the maximum performance improvement that can be obtained where the model is unconstrained in how it moves. As such, it provides a measure of how good a parameterization strategy is and allows different strategies to be compared. The change in parametric effectiveness due to inserting multiple different CAD features can be calculated using a single adjoint analysis, therefore the computational cost is essentially independent of the number of parameterisation strategies being analysed. The described approach can be used to automatically add new features to the model, and subsequently allows the use of the newly-added parameters, along with the existing parameters to be used for optimization, providing the opportunity for a better performing product. The developed approach is applied on CAD models created in CATIA V5 for 2D and 3D finite element and computational fluid dynamics problems.

We present a simple algorithm to compute the straight skeleton and mitered offset surfaces of a polyhedral terrain in 3D, i.e., of a z-monotone piecewise-linear surface. Like its 2D pedant, the 3D straight skeleton is the result of a wavefront propagation process, which we simulate in order to construct the skeleton in (worst-case) time O(n 4 log n), where n is the number of vertices of the terrain. Any mitered offset surface can then be obtained from the skeleton in time linear in the combinatorial size of the skeleton.

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