Heat Transfer Convection - Definition, Examples, Types, FAQs

What is convection?

Convection definition:-

The flow of a fluid (liquid or gas) between locations of differing temperatures is known as convection.

Convection meaning:-

The movement of heat through a gas or liquid as the hotter parts rise and the cooler, heavier parts sink.

What is Convection?

The term "convection" refers to the movement of air.

The transfer of fluid molecules from high-temperature to low-temperature environments.

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Convection in physics:-

Convection is a heat transfer method that involves the movement of a heated fluid such as air or water.

Convection examples:-

1. A radiator is a device that emits warm air from the top and draws cooler air in from the bottom. A steaming cup of hot tea - When you drink a cup of hot tea, the steam you observe signals that heat is being transported into the air. Ice melts because heat from the air is transferred to the ice.
2. When water boils, the molecules that are denser sink to the bottom, and the molecules that are less dense rise, resulting in a circular motion of the molecules, which heats the water.
3. Warm water goes towards the poles as it approaches the equator, while cooler water moves towards the equator.
4. Warm-blooded animals use convection to circulate their blood, which helps to regulate their body temperature.

Convection Heat Transfer:-

The transfer of heat between two bodies via currents of moving gas or fluid is known as convective heat transfer. In free convection, warm air or water rises and is replaced by a cooler parcel of air or water as it moves away from the heated body.

To transport heat, convection necessitates the presence of matter. . Heat will always find a way to flow from higher to the lower system, when two systems have a temperature difference.

Convection Heat Transfer example-

Radiator

Types of convection:-

1. Forced convection
2. Natural convection

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1. Forced convection:-

Forced convection is a transport mechanism in which fluid motion is created by an external source (such as a pump, fan, or suction device). Nanofluid Applications for Heat Transfer Enhancement, 2017.

Forced convection example-

Forced convection occurs when external sources such as fans and pumps are utilised to induce convection. Utilizing water heaters or geysers for quick water heating, as well as using a fan on a hot summer day, are examples of forced convection.

2. Natural convection:-

Natural convection is a sort of flow in which the fluid motion is not generated by any external source (such as a pump, fan, or suction device). Gravity is the primary factor behind natural convection.

Natural convection example-

The phenomenon of the sea and land breeze is one of the most common examples of natural convection. During the day, there is a breeze from the sea. Both the sea and the land are heated by the sun. Land Breeze: When the scenario changes at night, this phenomenon arises

Convection occurs in :-

Convection occurs on a huge scale in atmospheres, oceans, and planetary mantles, and it is the heat transmission mechanism for a major portion of our sun and all stars' outermost interiors. During convection, fluid movement can be invisible or visible and rapid, as in a hurricane.

When particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy, this is called convection. Because hot liquids or gases are less dense than cold liquids or gases, they rise into cold locations. The colder, denser liquid or gas settles in the warmer portions

The air becomes heated by:-

Heat is transferred between the Earth's surface and the atmosphere by conduction, radiation, and convection. Because air is a poor conductor, the majority of energy transfer happens near the Earth's surface. Sunlight heats the earth during the day, which then heats the air directly above it via conduction.

Free convection:-

Natural convection, also known as free convection, is a mass and heat transport method in which fluid motion is caused solely by density variations in the fluid caused by temperature gradients, rather than by any external source (like a pump, fan, suction device, etc.).

Describe the process of convection:-

Convection is a heat transfer method that involves the movement of a heated fluid such as air or water. The tendency of most fluids to expand when heated—that is, to become less dense and rise as a result of the increased buoyancy—causes natural convection.

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Application of convection:-

1. Convection currents in the water pipes cool car engines. Water is an excellent conductor of heat away from the engine and into the radiator.
2. Convection currents are what cause land and sea winds.
3. Convection currents are rising air over land that glider pilots employ to maintain their gliders in the air.
4. Air conditioners are placed towards the room's ceiling to allow for the formation of convection currents. Cool, dry air is blown into the room by the air conditioner. Cool air sinks because it is denser. Warm air rises because of its less dense. The air circulated, and the temperature of the air fell to the ideal level over time.

Thermal convection-

What does the term "Thermal Convection" mean?

Heat convection is the physical movement of a fluid (liquid, gas, or plasma) from one area to another to transfer thermal energy. In liquids and gases, heat convection is frequently the primary mechanism of energy transmission. Convection is one of three primary ways of heat transport, along with conduction and radiation.

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