What is the transfer of heat by movement of heated liquids or gases?

Answer 1

There are three basic heat transfer mechanisms: Conduction, Convection and

Radiation. Heat transfer in opaque solids is just by Conduction. In gases and

liquids all three mechanism can contribute to heat transfer.

The Convection Mechanism of Heat Transfer is the transportation of heat by

the bulk motion of the fluid. If this motion is produced by buoyancy effects that

arise from the fluid having different temperatures (and so different densities) at different points, it is called Natural Convection. If the motion of the fluid is produced by a pressure gradient (like a fluid been forced to flow through a heated pipe),

the heat convection mechanism is called Forced Convection Heat Transfer.

Answer 2

Convection is the process of thermal energy (heat energy) transfer through movement of a fluid (liquid or gas).

In essence, a region of a material that is hot can be said to contain thermal energy and the physical transport of that material to a new place also transports the thermal energy.

Most often we discuss convection that occurs naturally as a result of density changes in a fluid as a result of temperature differences. It is like the old saying, "Hot air rises." What that means is hot air has a lower density than cold air and is more buoyant than the cold air around it and so is pushed upward. The same principle applies to most liquids and gasses. Convection currents, and the associated heat transfer, are the reason that insulation is put in the walls of a building. The insulation slows the movement of air and hence the rate of heat transfer. Normal insulation such as fiberglass does not do inhibit thermal conduction or radiative heat transfer which are the other two forms of heat transfer.

One also hears the term, "forced convection" which usually means moving air with the use of a fan or blower, though the term can be perfectly well applied to any forced movement of any fluid. This also transfers thermal energy from one location to another, of course, and is the way most modern homes are heated and cooled.

Answer 3

One form of heat movement in heated liquids is enjoyed in a domestic boiler cum radiators system. Here the boiler heats the water which is then pumped to the room radiators before being returned to the boiler. The so-called "radiators" are not principally radiators although some heat is radiated from them. More heat is transferred by convection when the hot radiator heats the air next to it.

The classical name for heat transfer in liquids is Convection due to currents within the liquid caused by hotter liquid being less dense than colder liquid.

In times past when houses had a "back boiler" tank connected to a hot water cylinder upstairs it was these convection currents which caused the heated water from the boiler to rise up to the cylinder, and the colder water to descend to the back boiler.

In the case of gases hardly any heat is transferred by conduction or radiation, being transferred almost entirely by convection due to hotter gases being less dense than colder ones.

Answer 4

Both. Heat contain in matter and if the matter is in motion then heat going with it. The flow of energy with matter is called convection heat transfer.

Answer 5

you add heat to each of it

Answer 6

convection

Answer 7

Convection