Search results
Results from the WOW.Com Content Network
Convection, especially Rayleigh–Bénard convection, where the convecting fluid is contained by two rigid horizontal plates, is a convenient example of a pattern-forming system. When heat is fed into the system from one direction (usually below), at small values it merely diffuses ( conducts ) from below upward, without causing fluid flow.
Convection is usually the dominant form of heat transfer in liquids and gases. Note that this definition of convection is only applicable in Heat transfer and thermodynamic contexts. It should not be confused with the dynamic fluid phenomenon of convection , which is typically referred to as Natural Convection in thermodynamic contexts in order ...
Atmospheric convection is the vertical transport of heat and moisture in the atmosphere.It occurs when warmer, less dense air rises, while cooler, denser air sinks. This process is driven by parcel-environment instability, meaning that a "parcel" of air is warmer and less dense than the surrounding environment at the same altitude.
Also actiniform. Describing a collection of low-lying, radially structured clouds with distinct shapes (resembling leaves or wheels in satellite imagery), and typically organized in extensive mesoscale fields over marine environments. They are closely related to and sometimes considered a variant of stratocumulus clouds. actinometer A scientific instrument used to measure the heating power of ...
Convection is caused by yeast releasing CO2. In 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 convection currents, which are the key characteristics of a convection cell. When a volume of fluid is heated, it ...
Convection occurs when the Earth's surface, especially within a conditionally unstable or moist atmosphere, becomes heated more than its surroundings and in turn leading to significant evapotranspiration. Convective rain and light precipitation are the result of large convective clouds, for example cumulonimbus or cumulus congestus clouds. In ...
The first case is when natural convection aids forced convection. This is seen when the buoyant motion is in the same direction as the forced motion, thus accelerating the boundary layer and enhancing the heat transfer. [5] Transition to turbulence, however, can be delayed. [6] An example of this would be a fan blowing upward on a hot plate.
When natural convection isn't a significant factor, mathematical analysis with forced convection theories typically yields accurate results. The parameter of importance in forced convection is the Péclet number, which is the ratio of advection (movement by currents) and diffusion (movement from high to low concentrations) of heat.