Convection is the process of heat transfer through fluids such as liquids and gases. It occurs due to the movement of matter, which can be caused by differences in temperature, density, or other material properties. There are two types of convection: natural and forced. Natural convection occurs when fluids expand when heated, become less dense, and rise due to increased buoyancy. Forced convection, on the other hand, involves the transport of fluid by methods other than that resulting from variation of density with temperature.
Some key features of convection include:
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Convection coefficient: The heat transferred to a system is practically proportional to the convection coefficient, its area, and the temperature difference.
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Convection current: This is the movement of the substance caused by uneven heating and cooling due to convection.
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Buoyancy: This is the force that causes fluids to rise when heated and become less dense.
Examples of convection include the heating of water in a kettle or air in a heated room, which is caused by natural convection. Forced convection can be seen in the use of water heaters or geysers for instant heating of water and using a fan on a hot summer day. Convection is an important process in many fields, including meteorology, fluid mechanics, and chemical engineering.
