Effect of wing form on the hydrodynamic characteristics and dynamic stability of an underwater glider

TLDR

A glider is proposed for subsea payload delivery, where hydrodynamic forces and dynamic stability critically affect endurance and operation. The study develops a prototype underwater glider for subsea payload delivery and investigates rectangular versus tapered wing forms to identify the optimal design. Hydrodynamic characteristics were measured via tow‑tank resistance tests on models with rectangular and tapered wings, and steady‑state CFD used the test coefficients to compute lift, drag, and hydrodynamic derivatives across angular velocities. Results show the rectangular wing generates larger lift but a reduced stability envelope, whereas the tapered wing yields lower lift yet improved dynamic stability.

Abstract

We are developing a prototype underwater glider for subsea payload delivery. The idea is to use a glider to deliver payloads for subsea installations. In this type of application, the hydrodynamic forces and dynamic stability of the glider is of particular importance, as it has implications on the glider's endurance and operation. In this work, the effect of two different wing forms, rectangular and tapered, on the hydrodynamic characteristics and dynamic stability of the glider were investigated, to determine the optimal wing form. To determine the hydrodynamic characteristics, tow tank resistance tests were carried out using a model fitted alternately with a rectangular wing and tapered wing. Steady-state CFD analysis was conducted using the hydrodynamic coefficients obtained from the tests, to obtain the lift, drag and hydrodynamic derivatives at different angular velocities. The results show that the rectangular wing provides larger lift forces but with a reduced stability envelope. Conversely, the tapered wing exhibits lower lift force but improved dynamic stability.