Energy & Green Tech

How to make full use of wind energy in a compact city

Wind can be used as a renewable energy source that is clean, uncontaminated, and inexhaustible. Such characteristics have helped wind energy technologies to a key contributor to sustainable development in society, which is ...

Software

Software tool breathes life into post-COVID office airflow

As offices nationwide spring back to life, interior space designers and architects will soon have an easy-to-use planning tool to place indoor workplace furniture, staff, partitions and ventilation in a manner that maximizes ...

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?

Engineering

Using waste heat to power an environmentally sustainable future

In his most recent published research, appearing in Applied Thermal Engineering, City, University of London's Dr. Martin White explores a novel organic Rankine cycle system, based on a two-phase expansion through numerical ...

Engineering

A fluid-magnetic solution for sorting plastic waste

With the ever-increasing worldwide mass production of plastic, the inefficiency of current plastic recycling strategies has raised several environmental, societal, and economic concerns. Magnetic density separation (MDS) ...

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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