Hydraulics Videos

Water Hammer Explained

Water Hammer Wave Reflection and Valve Closure Time

Waterfall Flow & Air Blockages in Pipes Explained

Youtube video- Hydraulic Modelling with Modelica & SimulationX

Youtube video- Hydraulic Modelling and design using SimulationX

YouTube video - Hydraulic modelling using wanda

Youtube video- Surge analysis of pump trip

Comments and Questions

  • Sean Bell

    Hi Mike – just watched your video on waterfall and airlocks within piped systems (loved it) and have a couple of queries I would greatly appreciate some more insight on. Firstly the H2 loss – does the gravitation gain (generated on the negative flow gradient) contribute to reducing the H2 loss? Or could this create higher velocities with the increased pressure aiding in H2 loss? If not – pending on the specifics of the systems (pipe dia, fluid viscosity, velocities, densities) would it be possible to design a potable water system that the gravitation gain on the negative flow gradients be greater than the calculated H2 loss? Secondly towards the end of the video you touched on large infrastructure mains where you typically see larger dia’s and pressures with lower velocities – would you suggest a higher velocity and pressure to mitigate a) vaporization within water systems pending temperature ranges and b) to help push the gas along the highest point? All the best and look forward to watching the other videos

  • Once you have a bubble that is stuck at a high point you always get head loss. Its exactly like the flow of water over a waterfall or weir. The potential head after the weir or waterfall is always reduced by the amount of drop.

    Using higher velocity to push the gas along is often counter productive because the friction loss is proportional to the velocity squared. So you may reduce the waterfall flow losses but increase the friction flow losses more. So there is no easy answer to this question, it depends on the system.