"100 Hz to 600 Hz & low amplitude".
i) Less than 0.6 Bar Amplitude
ii) A wide range of frequencies varying with flow velocity.
iii) Most at beginning, at mid stroke high velocity, & end.
Flow making swirls as it goes across a valve seat into a pocket that does not have its eddy corners or "backwaters" designed out of it.
None - to pump or pipe.Forget unless someone has specified a level of residual fluctuation that is regardless of frequency, I.E. is applicable to all frequencies. Can be very disturbing to instruments though.
Use a "PulsView" analysis with PreFill pressure set at 9.0 times line pressure & volume of liquid in the "piping base" set at a 100 times volume b per stroke - if it goes away use an "Waveguard". At these frequencies the "negative amplitude response characteristics" will be >100:1
See 8 pags of hints and advice for"PulseView" Analysis.
Liquid Dynamics provides pipeline and pump user problem analysis, diagnostics, and prediction by software. For water hammer and shock solutions pulsation dampening and shock alleviating devices can be obtained from our associate websites PulseGuard and ShockGuard. |
For Hardware see our associate websites: |
www.PulseGuard.com and www.PulseGuard.co.uk for further information about pulsation dampeners and pumping systems. |
www.Shock-Guard.com and www.ShockGuard.co.uk to find large gas bag vessels, jumbo bladders, float separator and big bellows type pipeline shock attenuators and expansion / contraction volume compensators. |
www.Pulsation-Dampers.co.uk for more about pulse dampers in pumping systems and water hammer. |
| Water Hammer and www.Shock-Alleviators.co.uk for more on water hammer, pump start up surge, shut down back flow, & valve closure hammer. |
www.Accumulators-Hyd.com and www.Accumulators.co.uk for information about energy saving in pumping systems, standby emergency power, and safety shutdown systems. |
www.Pulsation-Shock.com for a quick view of how each different type of pulse dampener is matched to a pump installation. Pumps make flow, system resistance to flow is pressure, systems make pressure and pressure pulsation. |
www.Flow-Guard.com to find protection against excess flow. Guard against toxic spills when pipes burst, guard against gushers and fluid loss when hoses split, Flow-Guard guards against excess flow floods. |