Reducing bluff-body drag
Axisymmetric bodies traveling at high speed suffer from significant drag caused by the low pressure at the base. Recent high-fidelity numerical work has significantly contributed to the understanding of the near-wake development and has been shown to reproduce laboratory experiments with high accuracy.
Thus, in the present project different simulation strategies, ranging from fully resolved direct numerical simulations (DNS) to hybrid RANS/LES approaches, will be employed to study control strategies for the reduction of the base drag. The purpose of these studies is twofold: (1) to cause substantial changes in these base flows that would lead to improved flight vehicle performance; and (2) to further basic understanding of these complex, separated, compressible, turbulent flowfields. In contrast to previous attempts of using passive control, such as boat-tailing or steady base-blowing, the current project is concerned with active control, attempting to find the optimal (unsteady) actuation required to minimise drag.
Leader: Richard Sandberg
Collaborators: Jimmy Philip
Optimisation of resources and infrastructure
coherent structures; drag reduction; fluid dynamics; turbulence