Liquid Dynamics
Pulsation Analysis, Diagnostics, Prediction by Software
Pipeline and Pump user Problem -

Pulsation Analysis, Diagnostics, Prediction by Software

LIQUID DYNAMICS Ltd. offer Pulsation / Vibraton and Shock - Analysis & Diagnostics + Software Models
Please call toll free USA 1-888-326-7377 WE HAVE PEOPLE - Not voice mail. --44-161-480-9625 UK
Fluid Flow Control animations by Liquid Dynamics.

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LDi Catalog Printable PDF23

"Witchcraft and Black-boxery";

1. Everything is seen in hard copy, 2. in real time, large black and white,
3. from certified pressure calibrated transducers.

We agree with the skepticism, "you can make computer data say anything". We have even been shown so called pressure traces form totally different systems, to those under examination.
When it goes directly into a computer, you have no validation proof.
Oscilloscopes are fine, however when you have to play back to make a comparison, the operator thinks he can get away with showing you anything. There is only one solution. Hard copy; not just hard copy but high paper rate copy. Copy where a full 110mm width can be allocated to one of multiple channels, where the paper streams out at not less than 200mm per second, 8 dots per mm, & 250 kHz real time.
In street language that means you can see evidence of events which occur in 0.65 of a millisecond, or you can clearly see 1000 + Hz activity.
The point is that now you have original detailed hard copy, playbacks are easily identifiable and valid at any scale, making truly substantial analysis possible.


When one dot = 5 "mil" 5/1000th of an inch - or - 0.125mm and is equal to 0.00065 seconds, it is essential to take a sample or reading more frequently. Unless the transducers have suitably responsive characteristics, all the best capture and printing, will be worthless.
A suitable transducer specification is :- A. Certified calibrated and with accuracy - including linearity, hysteresis and repeatability to 0.5% FSO B. Frequency response up to 10kHz C. 10 Volt DC out.
Then from the oscillograph to the computer an IEEE488.1 or similar, parallel interface with a transfer rate of not less than 1 Megabyte per second. All used with signal conditioners of 5 kHz response.

It is easy to hide events and claim success before and after, when one shows pressure BEFORE, then flow AFTER.

There are analysts who specialize in building electrical systems of resistances, applying an AC since wave, and calling it a simulation of a pipe system. There are step functions or discontinuities that are essential to understanding liquid mass transfer, that this methods neglects to simulate.
There are specialists who will instrument your system, stream the data on to a local computer, drag the data into their own computer periodically, via the Internet, and apply "triggering software" to alert them to abnormalities. They will call you days in advance to alert you to a valve going bad.
Then there are those, who believe that data capture of noise, is literally as good as experienced ears and a stethoscope.
Ldi are not in any of these categories. We believe in displaying and explaining enough for you so that you not need us in the future. Adding to the understanding of systems in our purpose.
Phone USA 910.270.2737
PO Box 506 Hampstead, NC 28443 USA
UK (for EC) --44(0)161-480-9625
PO Box 47, Stockport, UK SK3-OLH


Liquid Dynamics International provides pipeline and pump user problem analysis, diagnostics, prediction by software, pulsation analysis, piping system analysis, and piping system simulation. For water hammer and shock solutions pulsation dampening and shock alleviating devices can be obtained from our associate websites:

PulseGuard Inc., and Ltd. for further information about pulsation dampeners / pulsation dampers. - Pulsation Dampener - Pulsation Dampeners - Pulsation Dampers
PulseGuard für Deutschland - Pulsationsdämpfer and to find large gas bag vessels, jumbo bladders, float separator / big bellows type pipeline shock attenuators and expansion / contraction volume compensators, surge alleviators, and shock alleviators. - Surge Alleviators - Shock Alleviators and for information about energy saving in pumping systems, standby emergency power, safety shutdown systems, hydraulic accumulators, and hydropneumatic accumulators. - Hydraulic Accumulators - Hydropneumatic Accumulators 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 with flow fuses and breather bags
Flow-Guard - Flow Fuses and Breather Bags

Liquid Dynamics