Hydrodynamic features specific to the dynamic movements of an underwater glider

The purpose of this study was to show the influence of the underwater glider's motion on its hydrodynamic coefficients. The proposed drone was based on a scaled-down geometry of the DARPA suboff bare hull model that was equipped with wings and fins. A series of Computer Fluid Dynamics simulations were performed using the ANSYS Fluent software. It was shown that with the increase of the drone's rotational velocity, the detachment of flow on the wings was delayed, and thus, the overall lift was increased. The hysteresis present in the characteristics of hydrodynamic properties during pitching movement had higher amplitude with increased pitching frequency. It was concluded that the parameters of the underwater glider's motion can have a significant influence on its hydrodynamic properties. •The underwater glider's dynamic motion can significantly influence its hydrodynamic coefficients•Hysteresis loop of the hydrodynamic forces observed during fast pitching motion•Lift force increases during upward movement with the increase of pitching frequency due to delay of the flow separation