Automotive

Breakthrough in faster-than-sound jet engines

Almost 75 years ago, U.S. Air Force pilot Chuck Yeager became the first person to fly faster than the speed of sound. Engineers have been pushing the boundaries of ultrafast flight ever since, attaining speeds most of us ...

Computer Sciences

Turning a single photo into a video

Sometimes photos cannot truly capture a scene. How much more epic would that vacation photo of Niagara Falls be if the water were moving?

Computer Sciences

Researchers compute turbulence with artificial intelligence

For the first time, researchers at ETH Zurich have successfully automated the modeling of turbulence by combining fluid mechanics with artificial intelligence. Their project relies on fusing reinforcement learning algorithms ...

Engineering

Army computer models unveil secret to quieter small drones

It's no secret the U.S. Army wants its small unmanned aerial systems to operate quietly in densely-populated regions, but tests to achieve this can be expensive, time-consuming and labor-intensive according to researchers.

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Fluid

In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, no matter how small. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids.

In common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. For example, "brake fluid" is hydraulic oil and will not perform its required function if there is gas in it. This colloquial usage of the term is also common in medicine and in nutrition ("take plenty of fluids").

Liquids form a free surface (that is, a surface not created by the container) while gases do not. The distinction between solids and fluid is not entirely obvious. The distinction is made by evaluating the viscosity of the substance. Silly Putty can be considered to behave like a solid or a fluid, depending on the time period over which it is observed. It is best described as a viscoelastic fluid. There are many examples of substances proving difficult to classify. A particularly interesting one is pitch, as demonstrated in the pitch drop experiment currently running at the University of Queensland.

This text uses material from Wikipedia, licensed under CC BY-SA