Fluids

Fluids

What is it?

Fluids are substances whose molecules can flow past each other without causing cracks in the substance.

Give me an example!

When water is in a liquid state, it is a fluid. However, when it freezes and becomes a solid (or ice), it no longer flows. Fluids that flow very slowly (such as pancake syrup) are said to have a high viscosity.

Rotational and Irrotational Flow

Rotational and Irrotational Flow

What is it?

Rotational flow is when the particles of fluids are all rotating about their own axis in addition to their other movement. Irrotational flow is when the individual particles are not rotating around their axis.

Give me an example!

Water flows down a drain in a counterclockwise direction in the northern hemisphere, and in a clockwise direction in the southern hemisphere. That is because of the rotation of the individual water molecules combined with the acceleration due to gravity. By contrast, an example of irrotational flow would be the flow of water over a dam, in which the water flows straight down and rotation doesn't have an effect.

Continuum

Continuum

What is it?

A continuum is a line that traces the progress of something through space and time.

Give me an example!

Scientists often refer vaguely to the space/time continuum. This imaginary line traces the evolution of everything back to the beginning of time in one direction, and on until the end of time in the other direction. The "space" part of it means that all these things exist in space.

 

Drainage

Removal of groundwater or surface water, or of water from structures, by gravity or pumping. Emptying something accomplished by allowing  liquid to run out of it.

Imbibition

The act of Cinsuming liduids. The process of taking food into the body through the mouth. The act of drinking.

Imbibition and Drainage

Imbibition is a fluid flow process in which the saturation of the wetting phase increases and the nonwetting phase saturation decreases. (e.g., waterflood of an oil reservoir that is water-wet). Mobility of wetting phase increases as wetting phase saturation increases. Mobility is the fraction of total flow capacity for a particular phase.

If a water-wet rock saturated with oil is placed in water, it will imbibe water into the smallest pores, displacing oil. If an oil-wet rock saturated with water is placed in oil, it will imbibe oil into the smallest pores, displacing water.

Drainage is a fluid flow process in which the saturation of the nonwetting phase increases. Mobility of nonwetting fluid phase increases as nonwetting phase saturation increases e.g., waterflood of an oil reservoir that is oil wet  Gas injection in an oil or water wet reservoir. Pressure maintenance or gas cycling by gas injection in a retrograde condensate reservoir. A water-wet reservoir that accumulation of oil or gas in a trap does so by drainage.
 

Primary and waterflood oil recovery is affected by the wettability of the system. A water-wet system will exhibit greater primary oil recovery.

Ionosphere

Ionosphere

What is it?

The ionosphere is the layer of the earth's atmosphere starting around 70 or 80 kilometers above the earth's surface and extending up indefinitely. The ionosphere is above the mesosphere. The thermosphere is part of the ionosphere.

Give me an example!

The ionosphere is mostly composed of gasses that have been ionized by ultraviolet radiation from the sun and is jam-packed full of free electrons (not attached to atoms). But the coolest thing about the ionosphere is that it reflects radio transmissions, making it possible to bounce radio waves off of it and communicate with people in other hemispheres!