In the context of heat and mass transfer, the term " convection " is used to refer to the sum of advective and diffusive transfer.

Note that 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.

The term convection may have slightly different but related usages in different scientific or engineering contexts or applications.

The convection term is often written as

The term radiator in this context is misleading since most heat transfer from the heat exchanger is by convection, not radiation.

A third term, thermal transmittance, incorporates the thermal conductance of a structure along with heat transfer due to convection and radiation.

The air tends to rise in an updraft through the process of convection ( hence the term convective precipitation ).

Despite the name, radiators generally transfer the bulk of their heat via convection, not by thermal radiation, though the term " convector " is used more narrowly ; see radiation and convection, below.

One might expect the term " radiator " to apply to devices that transfer heat primarily by thermal radiation ( see: infrared heating ), while a device which relied primarily on natural or forced convection would be called a " convector ".

In practice, the term " radiator " refers to any of a number of devices in which a liquid circulates through exposed pipes ( often with fins or other means of increasing surface area ), notwithstanding that such devices tend to transfer heat mainly by convection and might logically be called convectors.

This can change due to the unsteadiness in the flow captured by ( the unsteady term ) or due to the motion of the fluid particle as it moves from one point to another, ( the convection term ).

Forced convection is a term used when the streams and currents in the fluid are induced by external means — such as fans, stirrers, and pumps — creating an artificially induced convection current.

It was in this work that he coined the term " convection " to describe a type of energy transfer.

Crossover is the term used to describe the tube that connects from the convection section outlet to the radiant section inlet.

In addition to the wide range of length and time scales and the associated computational cost, the governing equations of fluid dynamics contain a non-linear convection term and a non-linear and non-local pressure gradient term.

This is the convection or the advection term.

In plasma generators the superimposed forced convection may modify the picture somewhat.

The temperature gradient may also mean Vega has a convection zone around the equator, while the remainder of the atmosphere is likely to be in almost pure radiative equilibrium.

This may be caused by the disappearance of a helium convection zone near the surface.

Although an excellent conductor of heat, it has somewhat inferior volumetric heat capacity as cast iron or carbon steel, it loses heat to convection much faster than carbon steel, and it may be constructed much thinner than cast iron.

Strong convection upcurrents may allow the droplets to grow to nearly. 08 mm (. 003 in ) before precipitating as heavy rain from an active thundercloud.

Fluid movement during convection may be invisibly slow, or it may be obvious and rapid, as in a hurricane.

On astronomical scales, convection of gas and dust is thought to occur in the accretion disks of black holes, at speeds which may closely approach that of light.

Forced convection may happen by natural means, such as when the heat of a fire causes expansion of air and bulk air flow by this means.

However, flames may be maintained with any type of forced convection ( breeze ); or ( in high oxygen environments in " still " gas environments ) entirely from the minimal forced convection that occurs as heat-induced expansion ( not buoyancy ) of gases allows for ventilation of the flame, as waste gases move outward and cool, and fresh high-oxygen gas moves in to take up the low pressure zones created when flame-exhaust water condenses.

if forced convection may be neglected, whereas if natural convection may be neglected.

This heat may be transferred to the choke thermostat via simple convection, via engine coolant, or via air heated by the exhaust.

This may have prevented cratonisation and continent formation until the mantle cooled and convection slowed down.

Both heat transfer and layer analysis may be performed in large industrial applications, but in household situations ( appliances and building insulation ), air tightness is the key in reducing heat transfer due to air leakage ( forced or natural convection ).

On the other hand, if heat conduction is very low, a large temperature gradient may be formed and convection might be very strong.

This arrangement had the purpose to prevent heated gas to reach the thermocouple by natural convection.

Most the rainfall in the south-west is caused by Atlantic depressions or by convection.

In summer, a large proportion of the rainfall is caused by sun heating the ground leading to convection and to showers and thunderstorms.

They are driven only by convection and thus have a very low energy efficiency.

The cooling system was of the free convection type assisted by a fan driven from a pulley mounted at the front end of the crank shaft.

Growth occurs by a diffusion-reaction process, assisted by convection.

The mechanism is named after the effect of solar radiation passing through glass and warming a greenhouse, but the way it retains heat is fundamentally different as a greenhouse works by reducing airflow, isolating the warm air inside the structure so that heat is not lost by convection.

A greenhouse works primarily by preventing absorbed heat from leaving the structure through convection, i. e. sensible heat transport.

Gels suppress the thermal convection caused by application of the electric field, and can also act as a sieving medium, retarding the passage of molecules ; gels can also simply serve to maintain the finished separation, so that a post electrophoresis stain can be applied.

The geothermally heated water then rises back toward the surface by convection through porous and fractured rocks.

In humans, the skin hairs lie flat in hot conditions, as the arrector pili muscles relax, preventing heat from being trapped by a layer of still air between the hairs, and increasing heat loss by convection.

In fluid dynamics, laminar flow is a flow regime characterized by high momentum diffusion and low momentum convection.

The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.

When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.

They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature.

At the lower end of the power rating range, dry and liquid-immersed transformers are often self-cooled by natural convection and radiation heat dissipation.

The oil-filled tank often has radiators through which the oil circulates by natural convection.

Another effect of buildings is the blocking of wind, which also inhibits cooling by convection.

Ting Huan's device, driven by convection, hung over a lamp and was called chao hua chich kuan ( the pipe which makes fantasies appear ).