The PCICE-FEM scheme for highly compressible axisymmetric flows

The recently developed PCICE-FEM scheme (Journal of Computational Physics, vol. 198, 659, 2004) is extended to two-dimensional axisymmetric geometries. The main discretization problem for nodal-based axisymmetric formulations lies in deriving a closed form as the radial coordinates approach zero along the axis of symmetry. This problem is addressed by employing the finite element piecewise linear approximations to both the flow variables and (separately) to the nodal values of the radial coordinates. The resulting formulation is an elegant treatment of the axisymmetric coordinate system with out noticeable loss of spatial accuracy and little additional cost in computational effort. An overview of the PCICE algorithm for the axisymmetric governing equations will be followed by a detailed axisymmetric finite element formulation for the PCICE-FEM scheme. The ability of the PCICE-FEM scheme to accurately and efficiently simulate highly compressible axisymmetric flows is demonstrated.