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Once the friction factors of the pipes are obtained (or calculated from pipe friction laws such as the Darcy-Weisbach equation), we can consider how to calculate the flow rates and head losses on the network. Generally the head losses (potential differences) at each node are neglected, and a solution is sought for the steady-state flows on the ...
The most common equation used to calculate major head losses is the Darcy–Weisbach equation. Older, more empirical approaches are the Hazen–Williams equation and the Prony equation. For relatively short pipe systems, with a relatively large number of bends and fittings, minor losses can easily exceed major losses.
When the pipe surface's roughness height ε is significant (typically at high Reynolds number), the friction factor departs from the smooth pipe curve, ultimately approaching an asymptotic value ("rough pipe" regime). In this regime, the resistance to flow varies according to the square of the mean flow velocity and is insensitive to Reynolds ...
In fact the specific weight of water is 9.8 kN/m 3 and the specific weight of mercury is 133 kN/m 3. So, for any particular measurement of pressure head, the height of a column of water will be about [133/9.8 = 13.6] 13.6 times taller than a column of mercury would be.
Use the following equation to calculate the free point from the rig floor: L sp = 735,294(X 2 − X 1)W dp ÷ F where L sp = depth of stuck point (ft), (X 2-X 1)= The stretch of the pipe from the reference point (in.), W dp = weight of drill pipe (lbs/ft), and F = the additional pull required (lbs.) It is important to note that the stretch test ...
The area required to calculate the mass flow rate is real or imaginary, flat or curved, either as a cross-sectional area or a surface, e.g. for substances passing through a filter or a membrane, the real surface is the (generally curved) surface area of the filter, macroscopically - ignoring the area spanned by the holes in the filter/membrane ...
S foot of water per foot of pipe; P d = pressure drop over the length of pipe in psig (pounds per square inch gauge pressure) L = length of pipe in feet; Q = flow, gpm (gallons per minute) C = pipe roughness coefficient; d = inside pipe diameter, in (inches) Note: Caution with U S Customary Units is advised. The equation for head loss in pipes ...
The above equations calculate the steady state mass flow rate for the pressure and temperature existing in the upstream pressure source. If the gas is being released from a closed high-pressure vessel, the above steady state equations may be used to approximate the initial mass flow rate. Subsequently, the mass flow rate decreases during the ...