Velocity of fluid

Measurement Applications. Lasers have been used for measurement of many physical parameters. These include length and distance, velocity of fluid flow and of soHd surfaces, dimensions of manufactured goods, and the quaHty of surfaces, including flaw detection and determination of... 

A final example of laser measurement techniques is measurement of the velocity of fluid flow (79) (see Flow measurement). If a laser beam is directed into a transparent fluid, some of the light may be scattered with a frequency shift zy given by... 

Venturimeler - to measure the velocity of fluid (D Probe to sense the velocity of fluid... 

Flow meter or sensor - To convert the velocity of fluid to the rate of flow... 

Once the number of tubes is determined, the flow velocity of fluid inside the mbes should be checked, using the criteria set forth for flow in pipes in Chapter 8 of Volume 1. 

Reynolds Re Velocity of fluid Density of fluid Viscosity of fluid Dimension of surface... 

Elutriation differs from sedimentation in that fluid moves vertically upwards and thereby carries with it all particles whose settling velocity by gravity is less than the fluid velocity. In practice, complications are introduced by such factors as the non-uniformity of the fluid velocity across a section of an elutriating tube, the influence of the walls of the tube, and the effect of eddies in the flow. In consequence, any assumption that the separated particle size corresponds to the mean velocity of fluid flow is only approximately true it also requires an infinite time to effect complete separation. This method is predicated on the assumption that Stokes law relating the free-falling velocity of a spherical particle to its density and diameter, and to the density and viscosity of the medium is valid... 

Figure 1.53. Relationship between precipitated amount of barite and velocity of fluid at 200°C. v velocity (m/s), Csai initial concentration of Ba.

The resulting equation for the velocity of fluid exiting the leak is... 

The dependence of (-AP) on the superficial velocity of fluid, us, flowing upward through a bed of particles is shown schematically in Figure 23.4 (after Froment and Bischolf, 1990, p. 570). The plot is leg (-AP) versus leg us, for given fluid and particle properties. 

At sufficiently high velocity of fluid upward through a bed of particles, the particles become entrained and do not settle that is, the particles are carried up with the fluid. Elutriation is the selective removal of particles by entrainment, on the basis of size. 

The average velocity of fluid in the reactor tube = (total flow)/(cross-section of the tube), i.e. 

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