Boundary Layer Transition Assessment on a Slender High-Speed Vehicle

Abstract

To anticipate the aerodynamic performance of a slender high-speed vehicle throughout a trajectory, the correct determination of transition onset and extent are crucial parameters in the overall evaluation. Though various methods and correlations are worked out on canonical geometries such as flat plates and cones, the present paper will primarily focus on a slender high-speed vehicle concept. Apart from small leading edge radii and 3D flow effects, also practical considerations are included such as gaps and steps indivertibly present due to manufacturing and integration, differential thermal expansion at dissimilar material interfaces, joints etc... A preliminary assessment based on empirical correlations is challenged by a detailed experimental campaign supported by numerical CFD computations. Their applicability range and their limitations are assessed related to the observed flow phenomena.