Discharge orifice diameter

The two most similar equations in Table 24.3 are 24.3.ii and 24.3.iii, derived by Inamura and Nagai [31] and Elkotb et al. [32], respectively. However 24.3.ii contains film thickness as a variable, while 24.3.iii contains the discharge orifice diameter. Since the two variables are different, the equations cannot be compared. However, the effects of each variable individually are considered in Fig. 24.20. The constants were set as follows We = 10,000, Re = 10,000 and GLR = 10. By inspection it is obvious that this formula is not dimensionally correct. Reynolds number is said to have a larger impact on SMD than the Weber number. This implies that liquid viscosity is more crucial than surface tension. 

The rate of discharge of solids through the outlet orifice is substantially independent of the depth of solids in the hopper, provided this exceeds about four times the diameter of the hopper, and is proportional to the effective diameter of the orifice, raised to the power 2.5. The effective diameter is the actual orifice diameter less a correction which is equal to between 1 and 1.5 times the particle diameter. 

The value of the coefficient of discharge Cd for orifice meters depends on the properties of the flow system, the ratio of the orifice diameter to the upstream diameter, and the location of the pressure-measuring taps. Values of Cd for sharp-edged orifice meters are presented in Fig. 14-55. These values apply strictly for pipe orifices with throat taps, in which the downstream pressure tap is located one-third of one pipe diameter from the downstream side of the orifice plate and the upstream tap is located one pipe diameter from the upstream side. However, within an error of about 5 percent, the values of Cd indicated in Fig. 14-55 may be used for manometer taps located anywhere between the orifice plate and the hypothetical throat taps. 

Va = velocity of atomizing air at atomizer, ft/h Ds = diameter of pressure-nozzle discharge orifice, ft pj = density of dryer gas at exit conditions, Ib/ft ... 

Stokes-Cunningham correction factor for terminal settling velocity Elooding coefficient Discharge coefficient Diameter Bubble diameter Hole diameter Orifice diameter Cut size of a particle collected in a device, 50% mass efficiency Mass median size particle in the pollutant gas... 

Cp = coefficient of discharge d = orifice diameter for full scale AP, inch D = internal pipe diameter, inch... 

Coefficient of discharge C for a given orifice type is a function of the Reynolds number (based on orifice diameter and velocity) and... 

Where Q = total liquid flow rate, gpm n = number of orifices d = orifice diameter, inches h = liquid head loss across orifices, inches K = orifice discharge coefficient... 

The coefficient of discharge is a composite of several components that affect the flow. Two of these components are the coefficients of contraction and velocity. In this work no attempt was made to evaluate the components separately. According to Prandtl [ ] the coefficient of velocity differs considerably from unity for small orifices and low velocities w hen the ratio of the orifice diameter to the pipe diameter is small. For large openings and high velocities it is usually close to unity. 

Orifice discharge coefficients presented in this paper are for a very limited range of orifice diameters. Larger orifices could have been tested but due to the limited volume inside the dewar, the solid accumulation would always be a problem. Of more interest perhaps would be smaller sized orifices. There will be smaller sized holes produced by meteoroid... 

Equation 24.1. iii by Nukiyama and Tanasawa [15] is one of the most commonly used correlations for plain jet nozzles. However, it neglects the effect of the diameter of the discharge orifice. In their experiment though, Nukiyama and Tanasawa did investigate the effects of the exit orifice diameter, but concluded... 

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