Search results
Results from the WOW.Com Content Network
In many engineering applications the local flow velocity vector field is not known in every point and the only accessible velocity is the bulk velocity or average flow velocity ¯ (with the usual dimension of length per time), defined as the quotient between the volume flow rate ˙ (with dimension of cubed length per time) and the cross sectional area (with dimension of square length):
In physics and engineering, in particular fluid dynamics, the volumetric flow rate (also known as volume flow rate, or volume velocity) is the volume of fluid which passes per unit time; usually it is represented by the symbol Q (sometimes ˙). It contrasts with mass flow rate, which is the other main type of fluid flow rate.
A pitot tube is used to measure fluid flow velocity. The tube is pointed into the flow and the difference between the stagnation pressure at the tip of the probe and the static pressure at its side is measured, yielding the dynamic pressure from which the fluid velocity is calculated using Bernoulli's equation. A volumetric rate of flow may be ...
A velocity-type meter measures the velocity of flow through a meter of known internal capacity. The speed of the flow can then be converted into a volume of flow to determine the usage. There are several types of meters that measure water flow velocity, including jet meters (single-jet and multi-jet), turbine meters, propeller meters and mag ...
The choked velocity is a function of the upstream pressure but not the downstream. Although the velocity is constant, the mass flow rate is dependent on the density of the upstream gas, which is a function of the upstream pressure. Flow velocity reaches the speed of sound in the orifice, and it may be termed a sonic orifice.
law of the wall, horizontal velocity near the wall with mixing length model. In fluid dynamics, the law of the wall (also known as the logarithmic law of the wall) states that the average velocity of a turbulent flow at a certain point is proportional to the logarithm of the distance from that point to the "wall", or the boundary of the fluid region.
The velocity at all points at a given distance from the source is the same. Fig 2 - Streamlines and potential lines for source flow. The velocity of fluid flow can be given as - ¯ = ^. We can derive the relation between flow rate and velocity of the flow. Consider a cylinder of unit height, coaxial with the source.
Considering flow through porous media, a special quantity, superficial mass flow rate, can be introduced. It is related with superficial velocity , v s , with the following relationship: [ 5 ] m ˙ s = v s ⋅ ρ = m ˙ / A {\displaystyle {\dot {m}}_{s}=v_{s}\cdot \rho ={\dot {m}}/A} The quantity can be used in particle Reynolds number or mass ...