Velocity terminal settling

Fig. 14. Drag coefficient for terminal settling velocity correlation (single particle) where A represents Stokes law B, intermediate law and C, Newton s...

This relationship is exponential with respect to time t and with increasing time quickly approaches equation 7, where is known as the terminal settling velocity under gravity. 

Gravity Settlers Gravity can act to remove larger droplets. Set-thng or disengaging space above aerated or boiling liquids in a tank or spray zone in a tower can be very useful. If gas velocity is kept low, all particles with terminal settling velocities (see Sec. 6) above the gas... 

Ut Terminal settling velocity of particle under action of gravity m/s ft/s ft/s... 

From the standpoint of collector design and performance, the most important size-related property of a dust particfe is its dynamic behavior. Particles larger than 100 [Lm are readily collectible by simple inertial or gravitational methods. For particles under 100 Im, the range of principal difficulty in dust collection, the resistance to motion in a gas is viscous (see Sec. 6, Thud and Particle Mechanics ), and for such particles, the most useful size specification is commonly the Stokes settling diameter, which is the diameter of the spherical particle of the same density that has the same terminal velocity in viscous flow as the particle in question. It is yet more convenient in many circumstances to use the aerodynamic diameter, which is the diameter of the particle of unit density (1 g/cm ) that has the same terminal settling velocity. Use of the aerodynamic diameter permits direct comparisons of the dynamic behavior of particles that are actually of different sizes, shapes, and densities [Raabe, J. Air Pollut. Control As.soc., 26, 856 (1976)]. 

Estimate the water terminal settling velocity using ... 

Ut = Terminal settling velocity, ft/sec Fs = CoiTection factor for hindered settling p, po = Density of water or oil, Ib/ff ... 

Free-falling diameter Also known as sedimentation or Stokes diameter, the diameter of a sphere with the same terminal settling velocity and density as a nonspherical or irregular particle. 

Terminal Falling Velocity See Terminal settling velocity. 

Terminal settling velocity (ly). The terminal settling velocity is that achieved under free-fall conditions (see Chapter 2). 

Absolute Gas Temperoture, F ab5.,or R = Terminal Settling Velocity of Particle Under Action of Grovify jff./sec,... 

Terminal Settling Velocity of Particle os Colculoted from Stokes Low, ft./sec. 

The terminal settling velocity for single spheres can he determined using the contrasts for the flovv regime. 

Figure 4-9 is convenient for quick checks of terminal settling velocities of solid particles in air and in water [23]. 

Figure 4-8. Terminal settling velocity of particles in water. By permission, Lapple, C. E., Fluid and Particle Mechanics, 1st Ed., University of Delaware, Newark, 1954.

The minimum residence time as determined by Stokes Law terminal settling velocity is ... 

Vgq = terminal settling velocity of hydrocarbon droplets in aqueous phase in bottom of vessel, in./min flaq viscosity of aqueous phase, cp... 

Vo = Average velocity of gas, feet/sec. u, = Terminal settling velocity of particle under action of gravity, feet/sec. gL = 32.2 feet/sec. ... 

U(5 = Terminal settling velocity as calculated from Stokes Law, ft/sec... 

Vj = Average velocity of gas, ft/sec tv = Terminal settling velocity of hydrocarbon... 

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