Content Summary | A software package named Daedalus is presented for the design and analysis of airfoils. Daedalus is a collection of integrated geometry, analysis, optimization and visualization tools, which provide the ability to interactively construct and analyze standard airfoils using the NACA analytical equations and non-standard airfoils using the NURBS equations. Additionally, a database incorporating hundreds of airfoils is linked to Daedalus. Computational Fluid Dynamics (CFD) and mesh generation tools have been integrated, providing the ability to produce fast flow field calculations. Additionally, a Differential Evolution algorithm is embedded, in order to iteratively solve the inverse airfoil design problem, using a prescribed pressure (or velocity) distribution. Concerning the standard airfoil profiles, Daedalus supports various NACA-series and symmetrical biconvex airfoils. Airfoils are produced in the form of a distribution of points with variable density, in order to provide densely spaced points near the leading and trailing edges. Furthermore, by providing the coordinates and weights of the corresponding control points, the user can design non-standard section profiles using the NURBS equations. Additionally, the proposed software incorporates the ability of interpolating an existing airfoil using B-Splines polynomials. In this way a section described with a small number of surface points can be reconstructed with a desired density of points for producing acceptable computational meshes. Moreover, a new airfoil can be produced by slightly modifying an existing standard airfoil, by displacing the corresponding B-Splines control points of the interpolated initial airfoil. Besides the geometrical tools, Daedalus provides the capability of calculating the flow field around any airfoil, under prescribed flow conditions, using embedded mesh generation and analysis tools. By incorporating the geometrical design, the mesh generation and the flow analysis tools within the same software package, the airfoil design and evaluation procedure becomes automated, without the need of interaction and data transfer between different software packages. The above mentioned tools can be used in conjunction with a Differential Evolution optimizer, integrated within the software package, in order to solve the inverse airfoil design problem. The cost function to be minimized is the area of the difference between the target pressure distribution and the calculated one for each candidate solution.
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