what is convection?
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Convective heat transfer Convection is the transfer of thermal energy from one place to another by the movement of fluids. Although often discussed as a distinct method of heat transfer, convection describes the combined effects of conduction and fluid flow or mass exchange. Two types of convective heat transfer may be distinguished:
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What are Convection Currents? - Definition & Examples This lesson will define convection, explain how it works, and describe how convection creates currents. We will also go through some examples of convection in the world around us: campfires, weather systems and convection in the Earth's mantle.
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Whatâs the Difference Between a Conventional and a Convection Oven? It comes down to how the heat is distributed. Both convection and conventional ovens are powered by gas or electricity. But the heat source in a conventional oven is stationary, usually radiating from the bottom, while in a convection oven a fan circulates the hot air around the chamber. Convection ovens allow for even, fast cooking because the temperature stays more consistent, whereas conventional ovens can have pockets of warmer or colder air.
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Heat Conduction Heat Convection Convection is heat transfer by mass motion of a fluid such as air or water when the heated fluid is caused to move away from the source of heat, carrying energy with it. Convection above a hot surface occurs because hot air expands, becomes less dense, and rises (see Ideal Gas Law).
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Atmospheric Processes â Convection Convection is the transfer of heat by the actual movement of the heated material. Any substance that flows is considered a fluid. This includes such things as water, shampoo, sunscreen, and even honey. Although not necessarily obvious, even gases, such as air, can be classified as fluids.
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What is conduction, convection, and radiation? CONVECTION--. Thermal energy is transferred from hot places to cold places by convection. Convection occurs when warmer areas of a liquid or gas rise to cooler areas in the liquid or gas. Cooler liquid or gas then takes the place of the warmer areas which have risen higher.
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conduction Our Living Language : Heat is a form of energy that manifests itself in the motion of molecules and atoms, as well as subatomic particles. Heat energy can be transferred by conduction, convection, or radiation. In conduction heat spreads through a substance when faster atoms and molecules collide with neighboring slower ones, transferring some of their kinetic energy to them.
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CONVECTION HEAT TRANSFER THROUGH CONVECTION. Like conduction and unlike radiation, convection requires a medium. However, in conduction the heat is transferred from one molecule to another, whereas in convection the heated fluid itself is actually moving. As it does, it removes or displaces cold air in its path.
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What is conduction, convection, and radiation? As when heat transfer takes place on a fluid with non zero bulk velocity, the flow field condition changes and momentum of the fluid carries the internal energy, but the mode of heat transfer is conduction. Hence, conduction with updating the flow field by advection is responsible for what we call convection.
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- Convection probably starts as iron crystallizes on the surface of the inner core, about 5,000 kilometers beneath Earth's surface; lighter components like oxygen, sulfur, and silicon are excluded and rise toward the core-mantle boundary (CMB) 2,000 kilometers higher, where temperatures are a thousand degrees cooler.
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What is conduction, convection, and radiation? Radiation is a method of heat transfer that does not rely upon any contact between the heat source and the heated object as is the case with conduction and convection. Heat can be transmitted though empty space by thermal radiation often called infrared radiation.
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Convection heater A convection heater is  a heater which operates by air convection currents circulating through the body of the appliance, and across its heating element. This heats up the air, causing it to increase in volume and so become buoyant and rise. Oil heaters are an example of this kind of heating appliance.
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- This situation sets the scene for the onset of convection - the bulk flow or circulation of a fluid driven by differences in temperature. Convection in the atmosphere plays a vital role in two further mechanisms - quite apart from the emission of longwave radiation - whereby energy is transferred from the Earth's surface to the atmosphere. The first is the transfer of 'thermal' energy (often referred to rather loosely as 'heat') by a combination of conduction and convection.
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Heat Conduction Heat Convection. Convection is heat transfer by mass motion of a fluid such as air or water when the heated fluid is caused to move away from the source of heat, carrying energy with it. Convection above a hot surface occurs because hot air expands, becomes less dense, and rises (see Ideal Gas Law).
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Convection cell See also: Convection. In the field of fluid dynamics, a convection cell is the phenomenon that occurs when density differences exist within a body of liquid or gas.These density differences result in rising and/or falling currents, which are the key characteristics of a convection cell.ee also: Convection. In the field of fluid dynamics, a convection cell is the phenomenon that occurs when density differences exist within a body of liquid or gas.
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Energy showdown: conventional vs. convection electric ovens In conventional ovens, the heat comes from a single source which is usually at the bottom of the oven. Convection ovens feature a circulation system that moves air throughout the oven chamber to heat it evenly.
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What is conduction, convection, and radiation? Thermal energy is transferred from hot places to cold places by convection. Convection occurs when warmer areas of a liquid or gas rise to cooler areas in the liquid or gas. Cooler liquid or gas then takes the place of the warmer areas which have risen higher. This results in a continous circulation pattern.
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What is conduction, convection, and radiation? Another good example of convection is in the atmosphere. The earth's surface is warmed by the sun, the warm air rises and cool air moves in. Radiation is a method of heat transfer that does not rely upon any contact between the heat source and the heated object as is the case with conduction and convection. Heat can be transmitted through empty space by thermal radiation often called infrared radiation.
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Mantle convection Mantle convection is the slow creeping motion of Earth's solid silicate mantle caused by convection currents carrying heat from the interior of the Earth to the surface.[3][4] The Earth's surface lithosphere, which rides atop the asthenosphere (the two components of the upper mantle), is divided into a number of plates that are continuously being ...
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What Is a Convection Oven, and How Does It Work? What is a convection oven, and what does it do? Is it really that helpful in the kitchen? It's very simple, really: It's all about the fan. A convection oven deals with the problems of hot spots and uneven cooking like MaryWynn asked about yesterday by using a fan to circulate air and keep the temperature more steady. So, basically, a convection oven, in popular terminology, is an oven with a fan inside. Now, certain more scientifically-oriented members of the family would like to point out that all ovens are technically convection ovens.
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Convection Oven | Baking 101 Learn how to use your convection oven for baking cakes, cupcakes, cookies, breads and a lot more! Basically, a convection oven is an oven with a fan inside that helps in circulating air and keeping the temperature more steady; thus cooking the food faster.
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Convection 101: A Guide to Cooking With Fans The difference, of course, is that induction users have no choice but to learn; convection oven owners can simply use conventional cooking modes. But like induction, convection is an almost indisputably superior cooking technology. After all, it can reduce cooking times and improve the overall quality of food.
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What is a Convection Oven? Convection ovens are often more expensive than standard, or radiant, ovens, but they cook food faster, at a lower temperature, and often with better results. Fans ensure that the same temperature reaches the top and bottom of foods, as well as foods at all rack levels.
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Convection In the context of heat and mass transfer, the term convection is used to refer to the sum of advective and diffusive transfer. In common use the term convection may refer loosely to heat transfer by convection, as opposed to mass transfer by convection, or the convection process in general.
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convection convection. Air heated by a space heater rises and is replaced by cool air, creating a convection current that circulates hot air throughout a room.
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Microwave oven A convection microwave oven is a combination of a standard microwave and a convection oven. It allows food to be cooked quickly, yet come out browned or crisped, as from a convection oven. Convection microwaves are more expensive than conventional microwave ovens.