Great stuff. For long pipelines, this is great. But in systems within a building, the pressure drop in the length of the pipe is trivial compared to all the other 'minor losses' (elbows, valves, fittings...). Perhaps a video discussing these factors?

A really good video. Thanks for sharing and keep doing more videos

Excellent video, very clear explanation and very helpful! Thank you from a fellow South African :)

Great 👍🏻 thanks. Could you please prepare a similar video for air as a fluid and required blower head

Beautifully explained. Please do explain steam with a simple example. You are a great teacher. Thank you very much for your efforts and teaching.

To date I am yet to find a 125NB / 5.0" pipe. Thank you for an awesome reminder of why the rules of thumb guide you to proper design boundaries

Great video 👍🏻

Great video Pat, very informative. Can I ask if you have done a video on two pumps in parallel and the effect of pressure and flow rate..... Thanks in advance

The equation that you used on the video to calculate the friction factor is very different from the one in Churchill's article. Can you explain the transformation of the original equation into the one you used?

Hi Pat, I just discovered your channel so, you might have covered this topic, but here it is: So you mentioned compressible flow, and I have a problem involving that. I have high pressure steam source at 30 bar and a 30 m long DN250 pipeline. The other end of the line is 20 bar. If I want to determine the max flow rate through the line, I generally use similar equations as in this video, but for compressible flow and take into account the lower density and the 1,5 times big velocity. OK. But what happens, when I blow to the atmosphere? The pressure difference is greater so the mass flow has to be at least as great as in the fist place, right? But due to the 30 times more velocity, at the end of the pipe, the gas goes with something like 4000 m/s. Not possible. If it was a valve, then chocking would occur, and the flow rate could be calculated from Kv. The max velocity is the speed of sound. But it is a long pipe not a sudden contraction. So what happens here? There is a pressure drop of ~10 bar at the exit point? Or the last meter determines the flow with the max velocity - meaning the flow is smaller than in the 20 bar case? Or 4000 m/s is correct, since it is just a couple of mm-s at the end? How would you solve this?

Hi Pat! Looking again your video two fundamental questions came to my mind and I would like to see your reply. 1) A pump creates pressure or flow? 2) When the speed of a pump increases why the flowrate of the pump increases?

I would expect optimization curve may be 2 parellel 4 inch pipe will be cheaper

Hi Pat! As always I love your videos and I have a small comment. The expression of ΔPsystem that you have in excel includes three terms (friction+elevation+pressure at the lowest point). If I apply the Bernoulli equation and let's say point 1 is the start of downhill and point 2 the end of downhill (where the pressure is 1 bar). By applying bernoulli there P1+ρgh1+(1/2)ρ(u1)^2=P2+ρgh2+(1/2)ρ(u2)^2+htotal, where u1=u2, you can eliminate them and then you have: P1+ρgh1=P2+ρgh2+htotal where htotal=2fρu^2L/D h2=0 Why do you consider as ΔPsystem=P2-ρgh1+2fρu^2L/D? Instead I would say that P1=P2-ρgh1+2fρu^2L/D. What is your opinion about it?

I am having a doubt pumping from 15m to ground level let's say 0 m ,so elevation difference you have taken 0-15=-15m If I am pumping from 5m to 10 m elevation means =10-5= 5m right?

Hii..pat can u find the chocolate pipe size Flow - 2000 kg/hr Temperature - 40 °c Velocity - as u consider Please find ..

Please share the excel

I have doubt about friction equation used in excel sheet, where you used (1/-4log(XX))^2 where I think it should be (1/-2log(XX))^2 or -0.25/log(XX)^2 en.wikipedia.org/wiki/Darcy_friction_factor_formulae

If I use haaland equation my friction factor is a lot different about .026 and if I use Colebrook I get .026027. Am I doing something different or incorrect