Page 181 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

154 Applied Process Design for Chemical and Petrochemical Plants

Nomenclature F = Factor in Babcock's steam flow equation
F 0 = Friction pressure loss (total) at design basis, for a
A = Internal cross-section area for flow, sq ft; or area of system, psi, for process equipment and piping, but
orifice, nozzle, or pipe, sq ft. excluding the control valve
a = Internal cross-section area for flow in pipe, sq. in. Fe = Elevation factor for two-phase pipe line
a' = Fractional opening of control valve, generally FM= Friction pressure loss (total) at maximum flow basis,
assumed at 60% = 0.60 for a system, psi
a., = Orifice area, sq in. F 1 = Base friction factor, vacuum flow, Figure 2-43
aw = Velocity of propagation of elastic vibration in the F 2 = Base friction factor, vacuum flow, Figure 2-43
discharge pipe ft/sec = 4660/ (1 + Ki, B,.) l/2 f = Friction factor, Moody or "regular" Fanning, see
5
B = Base pressure drop for control valve from manufac- Note Figure 2-3
turer, psi fr = Turbulent friction factor, See Table 2-2
Br = Ratio of pipe diameter (ID) to wall thickness fg = Moody or "regular" Fanning Friction for gas flow
C = Condensate, lbs/hr (Equation 2-133); or for pipe, fTP = Two-phase friction for wave flow
Williams and Hazen constant for pipe roughness, 2
(see Cameron Table 2-22 and Figure 2-24); or flow (1/f) 1/ = Gas transmission factor, or sometimes termed effi-
coefficient for sharp edged orifices ciency factor, see Table 2-15, f = Fanning friction
factor
C' = Flow coefficient. for orifices and nozzles which equal
the discharge coefficient corrected for velocity of G = Mass flow rate of gas phase, pounds per hour per
approach= Cct/(1 - Wt)l/2 square foot of total pipe cross-section area
G' = Mass rate, lbs/ (sec) (sq ft cross section)
C' = C for Figures 2-17 and 2-18
C' = c' = Orifice flow coefficient GPM = Gallons per minute flow
Cct = Discharge coefficient for orifice and nozzles g = Acceleration of gravity, 32.2 ft/(sec) 2
C 01 = Diameter correction factor, vacuum flow, Figure 2-43 H = Total heat, Btu/lb
h = Average height of all vertical rises (or hills) in two-
C02 = Diameter correction factor, vacuum flow, Figure 2-43
phase pipe line, ft
C,. = Standard flow coefficient for valves; flow rate in
gpm for 60°F water with 1.0 psi � ressure drop across 01� h = Static head loss, ft of fluid flowing
the valve, = Q ! (p/62.4) (�P) ) 11 h, = Enthalpy of liquid at higher pressure, Btu/lb
C', = Valve coefficient of flow, full open, from manufac- h 2 = Enthalpy of liquid at lower or flash pressure, Btu/lb
turer's tables hr = hL = Loss of static pressure head due to friction of fluid
Cn = Temperature correction factor, vacuum flow, Figure flow, ft of liquid
2-43
hp = Enthalpy of liquid at supply steam pressure, Btu/lb
Cr2 = Temperature correction factor, vacuum flow, Figure hr = Enthalpy of liquid at return line pressure, Btu/lb
2-43
hL' = Head at orifice, ft of liquid
C1 = Discharge factor from chart in Figure 2-31
h' L = Differential static head or pressure loss across flange
C2 = Size factor from Table 2-11, use with equation on taps when C or C' values come from Figure 2-17 or
Figure 2-31 Figure 2-18, ft of fluid
cpl c, = Ratio of specific heat at constant pressure to that at hwh = Maximum pressure developed by hydraulic shock, ft
constant volume=k of water (water hammer)
D = Inside diameter of pipe, ft K = Resistance coefficient, or velocity head loss in equa-
2
D 1.1 = Hydraulic diameter, ft tion, hL = Kv /2g
d = Inside diameter of pipe, in. = di � = Orifice or nozzle discharge coefficient
d, = Equivalent or reference pipe diameter, in. Ki,, = Ratio of elastic modulus of water to that of the
metal pipe material (water hammer)
dH = Hydraulic diameter, or equivalent diameter, in.
k = Ratio of specific heat, cp/ c,
d., = Orifice diameter, or nozzle opening, in.
L = Pipe, length, ft
d 00 = Diameter of a single line with the same delivery
capacity as that of individual parallel lines d, and d2 Le = Equivalent length of line of one size referenced to
(lines of same length) another size, miles, ( or feet)
di = Inside diameter of pipe, in. Leq = Equivalent length of pipe plus equivalent length of
E = Gas transmission "efficiency" factor, varies with line fittings, valves, etc., ft.
size and surface internal condition of pipe L 01 = Length of pipe, miles