1. The problem statement, all variables and given/known data Hi, my first post here! I have a Thermodynamics resit over the summer and I'm trying to get my head around viscous flow, I'm stuck at a question and need help! Thanks :) Glycerine discharges to the atmosphere through a circular pipe 100mm in diameter. The gauge pressure 50m from the exit is 458 kPa. Data for glycerine: ρ=1260 kg/m^3, μ=0.9 kg/ms. Determine the volume flow rate Q for the following cases: (i) a horizontal pipe (verify the flow is laminar!) (Ans: 25 litres/s) (ii) a pipe inclined upwards by 20° (Ans: 13.5 litres/s) (iii) a pipe inclined downwards by 20° (Ans: 36.5 litres/s) 2. Relevant equations I thought this equation was the right one to use but my answer is totally wrong when I plug the numbers in, it's not a units thing either... Q = (∏d^4 / 128μ) * (ΔPloss / length) 3. The attempt at a solution I assumed the gauge pressure at the pipe exit is equal to atm pressure, so 100kPa - is this correct? The rest is just plugging numbers in. Am I missing something obvious here...?