Pressure Loss in Pipes connected in Series or Parallel
Calculate pressure loss in pipes connected in series or parallel.
Pipes in Series
For pipes connected in series the pressure loss is the sum of the individual losses:
dp = dp_{1} + dp_{2} + .. + dp_{n} (1)
where
dp = total pressure loss (Pa, psi)
dp_{1..n} = individual pressure loss in each pipe (Pa, psi)
The mass flow rate is the same in all pipes:
m = m_{1} = m_{2} = .... = m_{n} (1b)
where
m = mass flow (kg/s, lb/s)
Pipes in Parallel
For pipes connected in parallel the pressure loss is the same in all pipes:
dp = dp_{1} = dp_{2} = .... = dp_{n} (2)
The total mass flow is the sum of the flow in each pipe:
m = m_{1} + m_{2} + .. + m_{n} (2b)
The pressure loss in the equations above can be substituted with a generic expression for pressure loss like the D'ArcyWeisbach equation.
Related Topics

Fluid Mechanics
The study of fluids  liquids and gases. Involving velocity, pressure, density and temperature as functions of space and time.
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