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ⓘ Convection is the movement of heat because of the movement of warm matter. For example, atmospheric circulation moves warm air to cool places, causing wind. Win ..




Convection
                                     

ⓘ Convection

Convection is the movement of heat because of the movement of warm matter.

For example, atmospheric circulation moves warm air to cool places, causing wind. Wind, in turn, can enter and cool a room if the window is open. The movement of the clouds, the ocean currents and many types of heaters are examples of convection.

                                     

1. Forced convection and natural convection

Convection can happen naturally natural convection or because of a moving device forced convection ".

The fan is a device that produces the movement of the air artificially. The air in this case is moving because of the rotation of the fan. This is an example of "forced convection".

Natural convection happens because a fluid is lighter if is hot and it is heavier if is cold, so if a fluid has a hot part and a cold part, the hot part will naturally move upward and the cold part naturally moves downward. For example, if the water in a pot is hotter near the bottom because of the fire, it moves from the bottom to the surface. At the same time the water near the surface is colder so it moves to the bottom.

                                     

2. Convection currents

Convection currents occur when there are significant differences in temperature between two parts of a fluid. When this happens, hot fluids rise and cold fluids sink. This causes movements or currents in the fluid. Atmospheric circulation, for example, is made by convection currents.

                                     
  • Atmospheric convection like other convection is caused by temperature differences. This may be because the atmosphere is unstable. When parts of the
  • the Sun heats the Earth s surface, the ground heats the air above it. Convection makes the air rise and cool. When it cools to the dew point, clouds form
  • low atmospheric pressure, usually in association with weather fronts. Convective cells may form in the surrounding area of troughs and give birth to a
  • created convection when it was passing underneath a cold - core upper - level low. As the system rapidly continued westward, a lot of the convection stayed
  • association with the wave, and convection slowly increased as a result of the low. Early on September 28, a rapid increase in convection and a well - organized outflow
  • apartments of a building Convector heater, a heater which operates by air convection currents circulating through the body of the appliance Dielectric heating
  • very slowly in different directions. Their movement is driven by the convection currents in the magma. A plate can contain both oceanic and continental
  • the outer core are believed to influence the Earth s magnetic field. Convection in the outer core, combined with the Coriolis effect, gives rise to Earth s
  • suggestion that convection currents in the mantle play an important role in continental drift. Holmes showed us that thermal convection currents were strong
  • stellar atmosphere is the outer region of a star. It is found above the convection zone. The stellar atmosphere is divided into several layers: The photosphere
  • tropical wave moved off the coast of Africa late on August 20, and almost convective banding and a broad circulation. A large area of low pressure formed within
  • a gaseous state. There are three modes of heat transfer: conduction, convection and radiation. Tariq Muneer Jorge Kubie Thomas Grassie, Heat Transfer: