Fluid Mechanics seventh edition by Frank M. White · Problem P6.13
Viscous Flow in Ducts — Frank M. White
Physics — Fluid Mechanics · laminar-pipe-flow
Problem
A soda straw is 20 cm long and 2 mm in diameter. It delivers cold cola, approximated as water at 10°C, at a rate of 3 cm3/s. (a) What is the head loss through the straw? What is the axial pressure gradient ∂p/∂x if the flow is (b) vertically up or (c) horizontal? Can the human lung deliver this much flow?