Efficient Parameterization of Waverider Geometries

This paper summarizes the results of investigations into the development of parametric waverider geometry models, with emphasis on their efficiency, in terms of their ability to cover a large feasible design space with a sufficiently small number of design variables to avoid the ‘curse of dimensionality’. The work presented here is focused on the parameterization of idealized waverider forebody geometries that provide the baseline shapes upon which more sophisticated and realistic hypersonic aircraft geometries can be built. We consider three different aspects of rationalizing the decisions behind the parametric geometry models developed utilizing the osculating cones method. Initially, we discuss three different approaches to the design method itself. Each approach provides direct control over different aspects of the geometry for which very specific shapes would be more complex to obtain indirectly, thus enabling the geometry to more efficiently meet any related design constraints. We then look into a number of requirements and limitations that affect the available options for the parametric design-driving curves of the inverse design method. Finally, we estimate the performance advantages that open up with increasing flexibility of the design-driving curves in the context of a design optimization study. This allows us to reduce the risk of over-parameterizing the geometry model, while still enabling a variety of meaningful shapes. While we mainly used the osculating cones method here, most of the findings also apply to other similar inverse design algorithms.