Search results
Results from the WOW.Com Content Network
Buoyancy also applies to fluid mixtures, and is the most common driving force of convection currents. In these cases, the mathematical modelling is altered to apply to continua, but the principles remain the same. Examples of buoyancy driven flows include the spontaneous separation of air and water or oil and water.
An object immersed in a liquid displaces an amount of fluid equal to the object's volume. Thus, buoyancy is expressed through Archimedes' principle, which states that the weight of the object is reduced by its volume multiplied by the density of the fluid. If the weight of the object is less than this displaced quantity, the object floats; if ...
"Buoyancy is defined as being positive" when, in the absence of other forces or initial motion, the entering fluid would tend to rise. Situations where the density of the plume fluid is greater than its surroundings (i.e. in still conditions, its natural tendency would be to sink), but the flow has sufficient initial momentum to carry it some ...
The lifting power in air of hydrogen and helium can be calculated using the theory of buoyancy as follows: Thus helium is almost twice as dense as hydrogen. However, buoyancy depends upon the difference of the densities (ρ gas) − (ρ air) rather than upon their ratios. Thus the difference in buoyancies is about 8%, as seen from the buoyancy ...
Archimedes is credited with the discovery of Archimedes' Principle, which relates the buoyancy force on an object that is submerged in a fluid to the weight of fluid displaced by the object. The Roman engineer Vitruvius warned readers about lead pipes bursting under hydrostatic pressure.
Convection is single or multiphase fluid flow that occurs spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be
In physics, a fluid is a liquid, gas, or other material that may continuously move and deform (flow) under an applied shear stress, or external force. [1] They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear force applied to them.
Gases at high pressure can have a density exceeding that of some solids. Thus they can be used to levitate solid objects through buoyancy. [5] Noble gases are preferred for their non-reactivity. Xenon is the densest non-radioactive noble gas, at 5.894g/L. Xenon has been used to levitate polyethylene, at a pressure of 154atm.