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SUMMARYThe present paper is the second article in a three-part series on anisotropic mesh adaptation and its application to (2-D) structured and unstructured meshes. In the ÿrst article, the theory was presented, the methodology detailed and brief examples given of the application of the method to both types of grids. The second part details the application of the mesh adaptation method to structured grids. The adaptation operations are restricted to mesh movement in order to avoid the creation of hanging nodes. Being based on a spring analogy with no restrictive orthogonality constraint, a wide grid motion is allowed. The adaptation process is ÿrst validated on analytical test cases and its high e ciency is shown on relevant transonic and supersonic benchmarks. These latter test cases are also solved on adapted unstructured grids to provide a reference for comparison studies. The third part of the series will demonstrate the capability of the methodology on 2-D unstructured test cases.

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SUMMARYAn adaptive least-squares finite element method is used to solve the compressible Euler equations in two dimensions. Since the method is naturally diffusive, no explicit artificial viscosity is added to the formulation. The inherent artificial viscosity, however, is usually large and hence does not allow sharp resolution of discontinuities unless extremely fine grids are used. To remedy this, while retaining the advantages of the least-squares method, a moving-node grid adaptation technique is used. The outstanding feature of the adaptive method is its sensitivity to directional features like shock waves, leading to the automatic construction of adapted grids where the element edge(s) are strongly aligned with such flow phenomena. Using well-known transonic and supersonic test cases, it has been demonstrated that by coupling the least-squares method with a robust adaptive method shocks can be captured with high resolution despite using relatively coarse grids.