Review of flow stability and natural transition of boundary layers on underwater axisymmetric bodies

The laminar–turbulent transition in the bow boundary layers on underwater axisymmetric bodies is an important phenomenon in various flows, and has important influence on the flow noise. The flow stability theory is an important approach to study boundary layer transition. The four stages of the research progress on flow stability of the boundary layers on underwater axisymmetric bodies are introduced. Furthermore, the prediction methods of natural transition are introduced, including the empirical method and the semi-empirical method. The common methods to control the transition location are introduced, including changing the forebody shape, applying superhydrophobic coating, heating/cooling the wall, and blow/suction on the wall. Finally, based on the current research status, some suggestions are provided for the research of the transition in boundary layers on underwater axisymmetric bodies.