Hydrodynamic Design and Analysis

Hydrodynamic Design and Analysis Tool (HYDAT) is a unique set of computer programs developed at CSS and used for design and performance predictions of manned, autonomous, tethered, free swimming, and towed vehicles. Aspects addressed include weight and buoyancy calculations, nonlinear hydrodynamic coefficient prediction, nonlinear time-domain simulation, linearized and frequency-domain analysis, including transfer function calculations, and stability analysis. The nonlinear dynamic's of cable systems and even multibody vehicle systems may also be addressed. The design of a vehicle is a series of tradeoffs among the mission requirements, design constraints, and technology. The most recognizable design constraints are length, diameter, and weight, but one needs to consider the mission, environment, sensors, and a host or towing platform. Vehicle synthesis may then be performed to optimally size the subsystems to support the payload and mission requirements. HYDAT can then be used to optimize the vehicle shape to not only minimize drag, but to also minimize the vehicle's response to currents, waves, and even to host platform motions. Propulsion system sizing and optimization may also be performed to meet mission requirements. HYDAT can also be applied to vehicles that do not operate underwater.