Though in our world we see science and nature as two separate things then we find ourselves trying to decipher the physics behind various natural events. Whether it be something simple as the formation of the rainbows to complex decoding of the DNA, researchers love getting into the workings of natural phenomenons. We have learned many aspects of nature and some of them are clearly boring while others are truly fascinating. Among them, one of the interesting topics is the vortex. It could either be playful swirling in the cup of coffee or a sailors’ nightmare whirlpools.
What is a Vortex?
Now in the current scenario vortex has two definitions, one is purely scientific while the other deals with spiritual aspects. The latter is described as a field of energy that is produced by an individual upon being in a certain mindset and mood. For the purposes of this article, we will focus on the scientific vortex.
A fluid mass or gas that upon swirled in a circular motion at a certain velocity by various factors creates a cavity or vacuum at the center of the liquid which sometimes can reach the bottom of the body in which it is being created.
The science behind the Vortex
In vortices, there is a center imaginary line around which matter revolves. When the velocity of the matter moving around has a lower angular speed vortex compared to its inside speed, a vortex is formed where its interior is shaped like a tube. There are two types of fluid flow.
Forced Vortex: If any external force or torque is applied to engage the rotation of the fluid, then the flow which is now rotating is considered as a forced vortex.
Free Vortex: Opposite to the forced flow, where no force is applied to get the liquid rotating is known as a free vortex.
Examples of Vortices
- Wingtip Vortices: When an airplane reaches a certain height, due to the shape of its wings two separate regions of pressure are created. Above the wing, air pressure is lower and beneath it is higher. Naturally, air wants to flow from the high-pressure region to a low-pressure area and when the moisture is just right in the atmosphere, these mini or massive depending on the aircraft angular clouds are formed behind the wings which usually tilts downwards, unless an aircraft is landing.
- Tornados: One of the most infamous forms of vortices is undoubtedly tornados. These cause tremendous damage to both property and lives. Though they only appear for usually a couple of minutes, it is enough to cause a massive catastrophe, in some rare cases these can last over an hour. They appear during thunderstorms which are extremely strong and big, as the condensation happens the hot air near the ground is raised upwards where it collides with cool air. When that happens and if conditions are right, cool air starts to wrap around the hot air and it starts spinning resulting in a vortex pulling this rotating air downwards. However, it is not considered a tornado until it reaches the ground but when it does it is a scary event. The speeds of the tornados can be anywhere from 100 miles/hour to 200 miles/hour, also they are unpredictable when it comes to movement as they can change directions instantly.
- Whirlpool: Whirlpools are rotating bodies of water that are formed when high speed (low speed as well in some cases) are collided against some form of obstruction and start twisting in a certain direction. Where two oceans meet, a whirlpool can occur at these locations as well due to the difference in speed of water flow. Though many small whirlpools can appear and disappear just like they were formed and are usually harmless, others can be deadly and disastrous. If a boat is to get stuck in a whirlpool, it is sucked towards the center and starts to sink. It is often seen in many whirlpool accidents that even though the ship was wrecked, crew members who were alive were sucked in and stuck under the wreckage of the ship. Norway is known to have the most whirlpools in the world. Interestingly, when we drain water in the sink it is also a form of a whirlpool.
- Polar Vortex: One of the most important and dangerous vortices on our planet. Unlike tornados and whirlpools, the polar vortex has always been present during the winters over the sky of Antarctica for hundreds of years. It rotates in a tight circle which never causes us any issues, however, sometimes due to a change in temperature or pressure it can lose its axis and starts an irregular rotation which can span over many nations. Due to the drastic change in tropical and arctic temperatures, this vortex is formed. At present time, scientists are saying that the irregularity of its weakening is becoming more regular due to climate change.
- Bubble Ring: Toroidal bubble is a type of vortex ring which are formed when an air bubble underneath the water is formed in a way that creates a vortex around itself. These rings are usually disk-shaped and flow towards the surface of the water. One interesting property of these rings is that they spin fast underneath and begin to slowly fade as they near the surface. Dolphins and whales are often seen producing these rings.
Vortices like many other phenomena of nature are present in smaller forms to gigantic processes. Not only on our planet but other planets such as Saturn and Jupiter also have multiple vortices in the form of humungous tornados. Nonetheless, these are amazing events and the physics behind them is quite intriguing.