Convection

thumb|Simulation of thermal convection in the Earth's mantle. Hot areas are shown in red, cold areas are shown in blue. A hot, less-dense material at the bottom moves upwards, and likewise, cold material from the top moves downwards.

dimensionless quantity that is used to help predict similar flow patterns in different fluid flow situations

In the fields of physics, engineering, and earth sciences, advection is the transport of a substance or quantity by bulk motion of a fluid. The properties of that substance are carried with it. Generally the majority of the advected substance is also a fluid. The properties that are carried with the advected substance are conserved properties such as energy. An example of advection is the transport of pollutants or silt in a river by bulk water flow downstream. Another commonly advected quantity is energy or enthalpy. Here the fluid may be any material that contains thermal energy, such as wat

quotient of kinematic viscosity and thermal diffusivity for a fluid

(of a star) layer which is unstable to convection. Energy is primarily or partially transported by convection in such a region

characteristic number in fluid dynamics

measure of heat transfer on a surface

characteristic number for heat transfer into a body

characteristic number of heat transport in fluids

dimensionless ratio used in fluid dynamics

slow creeping motion of Earth's solid silicate mantle caused by convection currents carrying heat from the interior to the planet's surface.

physical phenomenon

oven that has fans to circulate air around food or objects

ventilation using solar energy

heating device

thumb|Thermosyphon circulation in a simple solar water heater (not a working model; there is no water supply to replenish the tank when the tap is used)

moving body of liquid or gas

phenomenon where granular material subjected to shaking will exhibit circulation patterns

natural convection, occurring in a plane horizontal layer of fluid heated from below, in which the fluid develops a regular pattern of convection cells known as Bénard cells

class of characteristic numbers named after Adrian Bejan

mechanism, or type of heat transport, in which the fluid motion is not generated by any external source, but only by density differences in the fluid occurring due to temperature gradients

laboratory equipment

effect

type of Fast moving cold weather front