Hydrodynamic in the context of Weather forecasting

Lubrication is the process or technique of using a lubricant to reduce friction and wear and tear in a contact between two surfaces. The study of lubrication is a discipline in the field of tribology.

Lubrication mechanisms such as fluid-lubricated systems are designed so that the applied load is partially or completely carried by hydrodynamic or hydrostatic pressure, which reduces solid body interactions (and consequently friction and wear). Depending on the degree of surface separation, different lubrication regimes can be distinguished.

In biology, any group of fish that stay together for social reasons are shoaling, and if the group is swimming in the same direction in a coordinated manner, they are schooling. In common usage, the terms are sometimes used rather loosely. About one quarter of fish species shoal all their lives, and about one half shoal for part of their lives.

Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate. It is also likely that fish benefit from shoal membership through increased hydrodynamic efficiency.

Bodyboarding is a water sport in which the surfer rides a bodyboard on the crest, face, and curl of a wave which is carrying the surfer towards the shore. Bodyboarding is also referred to as Boogieboarding due to the invention of the "Boogie Board" by Tom Morey in 1971. The average bodyboard consists of a short, rectangular piece of hydrodynamic foam. Bodyboarders typically use swim fins for additional propulsion and control while riding a breaking wave.

The Rayleigh–Taylor instability, or RT instability (after Lord Rayleigh and G. I. Taylor), is an instability of an interface between two fluids of different densities which occurs when the lighter fluid is pushing the heavier fluid. Examples include the behavior of water suspended above oil in the gravity of Earth, mushroom clouds like those from volcanic eruptions and atmospheric nuclear explosions, supernova explosions in which expanding core gas is accelerated into denser shell gas, merging binary quantum fluids in metastable configuration, instabilities in plasma fusion reactors and inertial confinement fusion.

USS Independence (LCS-2) is the lead ship of the Independence-class of littoral combat ships. It is the sixth ship of the United States Navy to be named for the concept of independence. The design was produced by the General Dynamics consortium for the Navy's LCS program, and competes with the Lockheed Martin–designed Freedom variant.

Independence, delivered to the Navy at the end of 2009, was a high-speed, small-crew corvette, although the U.S. Navy does not use the term, intended to operate in littoral waters. It can swap out various systems to take on various missions, including finding and destroying mines, hunting submarines in and near shallow water, and fighting small boats (it is not intended to fight warships). The ship is a trimaran design with a wide beam above the waterline that supports a larger flight deck than those of the Navy's much larger destroyers and cruisers, as well as a large hangar and a similarly large mission bay below. The trimaran hull also exhibits low hydrodynamic drag, allowing efficient operation on two diesel-powered water jets at speeds up to 18 knots (33 km/h; 21 mph), and high-speed operation on two gas turbine–powered water jets at a sustainable 44 knots (81 km/h; 51 mph) and even faster for short periods.

Fluid bearings are bearings in which the load is supported by a thin layer of rapidly moving pressurized liquid or gas between the bearing surfaces. Since there is no contact between the moving parts, there is no sliding friction, allowing fluid bearings to have lower friction, wear and vibration than many other types of bearings. Thus, it is possible for some fluid bearings to have near-zero wear if operated correctly.

They can be broadly classified into two types: fluid dynamic bearings (also known as hydrodynamic bearings) and hydrostatic bearings. Hydrostatic bearings are externally pressurized fluid bearings, where the fluid is usually oil, water or air, and is pressurized by a pump. Hydrodynamic bearings rely on the high speed of the journal (the part of the shaft resting on the fluid) to pressurize the fluid in a wedge between the faces. Fluid bearings are frequently used in high load, high speed or high precision applications where ordinary ball bearings would have shortened life or caused high noise and vibration. They are also used increasingly to reduce cost. For example, hard disk drive motor fluid bearings are both quieter and cheaper than the ball bearings they replace. Applications are very versatile and may even be used in complex geometries such as leadscrews.

Coastal morphodynamics refers to the study of the interaction and adjustment of the seafloor topography and fluid hydrodynamic processes, seafloor morphologies, and sequences of change dynamics involving the motion of sediment. Hydrodynamic processes include those of waves, tides and wind-induced currents. Anthropogenic climate change is causing changes in the coastal changes and processes that are interconnected with those caused by natural processes.

While hydrodynamic processes respond instantaneously to morphological change, morphological change requires the redistribution of sediment. As sediment takes a finite time to move, there is a lag in the morphological response to hydrodynamic forcing. Sediment can therefore be considered to be a time-dependent coupling mechanism. Since the boundary conditions of hydrodynamic forcing change regularly, this may mean that the beach never attains equilibrium. Morphodynamic processes exhibit positive and negative feedbacks (such that beaches can, over different timescales, be considered to be both self-forcing and self-organised systems), nonlinearities and threshold behaviour.