Discharge coefficient for orifices

Discharge coefficient for orifice and nozzles Diameter correction factor, vacuum flow. Figure 2-43 Diameter correction factor, v acuum flow. Figure 2-4.3... 

Measurements by Harris and MagnaU [Trans. Jn.st. Chem. Eng. (London), 50, 61-68 (1972)] with a venturi (p = 0.62) and orifices wiSi radius taps (P = 0.60-0.75) indicate that the discharge coefficient for nonnewtonian fluids, in the range Nr (generalized Reynolds number) 3500 to 100,000, is approximately the same as for newtonian fluids at the same Reynolds number. 

Cj = discharge coefficient for nozzles and orifices hL = differential static head or pres.sure loss across... 

Figure 2-18. Flow coefficient C for square edged orifices. By permission, Crane Co. [3], Technical Paper 410 Engineering Div. (1976) and Fluid Meters, Their Theory and Application Part 1, 6th Ed., 1971, American Society of Mechanical Engineers and, Tuve, G. L. and Sprenkle, R. E., Orifice Discharge Coefficients for Viscous Liquids, Instruments Nov. 1933, p. 201.

Flow coefficient for orifices and nozzles which equal the discharge coefficient corrected for velocity of approach = C / (1 - p" )V2... 

Cq = discharge coefficient for sharp-edged orifice = 0.61 for Reynolds Number > 30,000 and not sonic... 

According to Miller (1983), for NReo > 4000 the discharge coefficient for the venturi, as well as for the nozzle and orifice, can be described as a function of NReD and fi by the general equation... 

Figure 10-8 Orifice discharge coefficient for square-edged orifice and flange, corner, or radius type (From Miller, 1983.)...

C0 Orifice discharge-coefficient for gas passing through plate i... 

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. 

TABLE 10-4 Discharge Coefficients for Quadrant-Edge Orifices... 

The equation for the mass flow rate through a Venturi meter is the same as for the orifice meter. Equation 4.27. The discharge coefficient for a Venturi meter is larger and typically varies from 0.95 to 0.975 for the orifice meter the discharge coefficient typically varies from 0.6 to 0.7. For more information on the design and discharge coefficients of a Venturi meter see ASME MFC-3M-1989... 

Discharge coefficients for drilled-plate orifices. [From G. L. Tuve and R. E. Sprenkle, Orifice discharge coefficients for viscous liquids, Instruments 6 201 (1933). Reproduced by permission of the publisher.] I... 

Design of Pressure-relief Systems. Discharge rates are calculated by charts, tables, or equations supplied by manufacturers. In general, the method is to establish the discharge-pressure rates by code requirements and use fluid-flow calculation. for the pressure-relief devices, which behave as nozzles or orifice.s, and the associated piping. Discharge coefficients for pressure-relief devices can he approximated as follows ... 

Orifice discharge coefficients for liquid nitrogen are shown in Fig. 2 and for liquid hydrogen in Fig. 3. The triple-point pressures for both liquids are shown by the dashed vertical line on the respective curves. No discontinuity in the discharge coefficient appeared as the downstream pressure was raised or lowered through the triple-point pressure. 

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