convection

[ kuhn-vek-shuhn ]

noun

1. Physics. the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.
2. Meteorology. the vertical transport of atmospheric properties, especially upward ( advection ).
3. the act of conveying or transmitting.

convection

/ kənˈvɛkʃən /

noun

1. See conduction
   a process of heat transfer through a gas or liquid by bulk motion of hotter material into a cooler region Compare conduction
2. meteorol the process by which masses of relatively warm air are raised into the atmosphere, often cooling and forming clouds, with compensatory downward movements of cooler air
3. geology the slow circulation of subcrustal material, thought to be the mechanism by which tectonic plates are moved

convection

/ kən-vĕk′shən /

1. Current in a fluid caused by uneven distribution of heat. For example, air on a part of the Earth's surface warmed by strong sunlight will be heated by contact with the ground and will expand and flow upward, creating a region of low pressure below it; cooler surrounding air will then flow in to this low pressure region. The air thus circulates by convection, creating winds.
2. See Note at conduction

convection

1. The motion of warm material that rises, cools off, and sinks again, producing a continuous circulation of material and transfer of heat . Some examples of processes involving convection are boiling water, in which heat is transferred from the stove to the air; the circulation of the atmosphere of the Earth , transferring heat from the equator to the North Pole and South Pole ; and plate tectonics , in which heat is transferred from the interior of the Earth to its surface.

Derived Forms

• conˈvective, adjective
• conˈvectional, adjective

Other Words From

• con·vection·al adjective

Word History and Origins

Origin of convection¹

First recorded in 1615–25; from Late Latin convectiōn-, stem of convectiō “a bringing together”; equivalent to convect + -ion

Word History and Origins

Origin of convection¹

C19: from Late Latin convectiō a bringing together, from Latin convehere to bring together, gather, from vehere to bear, carry

Example Sentences

The physics of the design itself has been around for much longer than that—they’re essentially a refined design of the traditional convection oven.

From Popular-Science

Water vapor and air constantly circulate in turbulent convection currents.

From Science News For Students

That convection cycle puts Betelgeuse on a semiregular dimmer switch that fluctuates roughly every 400 days or so.

From Science News

The star’s temperature hadn’t dropped as much as would be expected if the dimming was from something intrinsic to the star, like its convection cycles, the pair reported in the March 10 Astrophysical Journal Letters.

From Science News

The convection technology in air fryers allows you to roast, bake, and even dehydrate your favorite foods.

From Popular-Science

The bag may be called a "convection shield," slowing convection-cooling due to air currents.

From Project Gutenberg

This mode of propagation may better be described as a convection of excitation.

From Project Gutenberg

This is illustrated by the seasonal variation in convection.

From Project Gutenberg

In summer, when the gradient is steepest, convection reaches its maximum.

From Project Gutenberg

In the part BNA, the electricity is carried by a moving conductor; it is said to be displaced by convection.

From Project Gutenberg

Related Words

• deportation
• relocation
• removal
• transmission

More About Convection

What is convection?

Convection is the transfer of heat by the movement of heated parts of liquids and gases. Convection happens in liquids and gases because, unlike in a solid, molecules are able to freely move.

For example, the air molecules in your living room continually move around, all moving at about the same speed. However, if you turn on an electric heater, the air particles close to the heater will get hotter, which means they will have more energy and will move faster. Faster-moving particles are less dense, or lighter, and will flow to the top of the living room. Colder particles are denser and will move down toward the floor when the hot particles move up. This movement of hot air is convection.

The cold particles that move toward the floor will now be close to the heater. They, too, will heat up and move faster. And just like the earlier particles, these particles will move up, pushing colder particles down. This cycle is called a convection current or a convection cycle. The cycle will continue until an outside force changes things, such as turning off the heater.

Why is convection important?

The first records of the term convection come from around 1615. It ultimately comes from the Latin word convectiō, meaning “a bringing together.” In convection, hot particles “gather together” at a high altitude or elevation.

Convection happens every day in nature. For instance, thunderstorms are formed through a convection cycle. Warm, moist air rises, while cooler air falls. Once it rises, it cools and the moisture in the air becomes water vapor. As the cycle continues, the water vapor will form a cloud. When a lot of water vapor forms, like during a humid day in the summer, a thunderstorm cloud can form. At some point, all that water vapor in the cloud will fall to the ground in the form of rain. The storm will continue as long as hot water vapor continues to feed the cycle.

Convection is also the reason we arrange heating and cooling equipment the way we do. Usually, air conditioners and cooling vents are placed high on the ceiling so that the cold air will fall toward the ground and cool you. Similarly, heaters and heating vents are placed low on the floor so that the hot air will rise up and heat your body as it does so.

Did you know … ?

Hail is also a product of convection. In fact, a hailstone has layers like a tree that you can count to see how many times it went through the convection cycle before it became too heavy and fell to the ground.

What are real-life examples of convection?

Convection is a common process that is responsible for weather patterns and wind movement.

Researchers say they've found the first chemical proof of volcanic convection on Mars while studying the Tissint meteorite that fell to Earth in 2011: https://t.co/Rg6sl0MnPb

— AccuWeather (@accuweather) September 23, 2020

#Teddy still has a good bit of deep convection near its center as evidenced by the cold cloud tops on this IR satellite loop. pic.twitter.com/LcOaCiyuEW

— Jake Mulholland, Ph.D. (@JakeMulholland1) September 23, 2020

 

What other words are related to convection?

• heat
• energy
• transfer
• liquid
• gas
• conduction

Quiz yourself!

True or False?

Convection occurs when hot particles move upward and cold particles move downward to replace them.