Hydromechanics facilities in MD
6 facilities
120 foot Towing Tank
Annapolis, MD
This tank is the workhorse of the Laboratory facilities. Ship models up to about six feet in length can be tested for seakeeping and resistance properties, and the tank is used extensively for demonstrations, midshipmen projects, and for research. The dual-flap wavemaker at the end of the tank is similar to the wavemaker in the 380 foot tank. Wavemaking techniques developed here can be reproduced in the larger facility. The tank is equipped to demonstrate constant force (gravity tow) and constant velocity (powered carriage) test methods. Data from the model are transmitted by a cable to recording equipment or to a networked computer workstation for processing.
380 foot Towing Tank
Annapolis, MD
Large models can vastly improve full scale predictions made from certain types of model tests. Ship models up to 25 feet in length can be tested in the Laboratory's 380 foot towing tank. This tank is equipped with two towing carriages, a dual flap wavemaker, a planar motion mechanism for maneuvering experiments, fans for simulating over-water winds, and has a high speed test towing capability. A drydock allows the set-up of underwater (submarine) experiments while the tank is in use for other tests. A host computer facility is contained within the control room. The computer is used to control the wavemakers and is used to process data. Control signals and data are transmitted between the carriage and the control room by a fiber optic cable system. Additionally, a self contained computer workstation on the towing carriage can be used to acquire and analyze experimental data.
Coastal Engineering Tank
Annapolis, MD
Ocean engineering students use this facility to study the effects of wave action on coastlines and coastal structures. The L-shaped tank is equipped with a wavemaker. Breakwaters, jetties, groins, and harbors can be designed, and their effectiveness evaluated. A moveable bridge structure serves as an observation platform, and as a mounting surface for instrumentation. The Laboratory also includes equipment for the study of the basic principles of soil mechanics as applied to coastal sediments. The tank is currently subdivided with a main test section, 52 ft long and 18 ft wide, containing a solid beach at a 1 to 10 slope.
David Taylor Model Basin Building
West Bethesda, MD
These three Towing Basins are used for a wide variety of hydrodynamic tests including: resistance, self-propulsion, static stability in calm water, open water propeller characterizations, self-propelled model steering maneuvers, unsteady propeller blade force measurements, wake surveys, knot-meter calibrations under simulated dynamic conditions, vertical and horizontal planar motion experiments, hydrodynamic forces on submerged bodies, foils, etc., towed body experiments, and longitudinal wave cut experiments. The High Speed Basin is used to measure hydrodynamic forces on hydrofoils, planing boats, and other high speed craft operating in calm water and in waves. The water level in the Shallow Water Basin can be varied to simulate rivers, canals, and restricted channels.
Rotating Arm Facility
West Bethesda, MD
The Rotating Arm Facility is used to measure hydrodynamic forces and moments and perform captive-model stability and control and propulsion experiments on surface ships, towed bodies, unmanned underwater vehicles, swimmer delivery vehicles, submarines, and torpedoes. Surface models up to 30 feet in length and submerged models up to about 22 feet can be tested in a controlled environment over a wide range of angles of attack and drift. Angular velocities can also be controlled. The forces and moments on the hull and appendages are required for accurate mathematical models. Commercial applications for this facility include maritime shipping industry and oceanographic engineering applications.
Water Channel
Annapolis, MD
The circulating water channel is used for flow visualization, measurement of force and pressure distribution on submerged bodies, and propeller thrust and torque measurement. The test section has a free surface, and pressure can be varied from +6 psi to -12 psi. This allows demonstration of cavitation effects on propellers and hydrofoil sections.