Numerical and experimental determination of velocity dependant Hydrodynamic derivatives of an underwater towed body

Underwater towed bodies are widely used for both civilian and military applications. Hydrodynamic stability is an essential requirement for the towed body in order to provide a stable platform for the payloads housed within them. Estimation of hydrodynamic derivatives of the towed body is an important pre-requisite for evaluation of hydrodynamic stability. Numerical and experimental evaluation of velocity dependant hydrodynamic derivatives is presented in this paper. Drift angle tests and rotating arm tests are numerically simulated for evaluation of the hydrodynamic derivatives. The numerical analysis results were experimentally validated through model experiments using Vertical Planar Motion Mechanism in a towing tank using a full scaled model of the towed body. Comparison between the numerical and experimental results is presented.