pressure pulsations in ships fuel system

[DYV1973]

LS,

What kind of pressure pulsations can be expected in a ships heavy fuel oil supply system (amplitude and frequency). And are there any regulations from classification agencies concerning these pulsations. (I have searched in GL rules, but haven't found them so far).

Thanks.

DYV

 

[jmw]

I assume you refer here to the high pressure circuit.
You may do well to ask the individual manufacturers.
I did have this information once, but I've now lost it and in any case the changes to engine design over recent years probably means it is out of date (common rail etc.) and whether it may vary significantly from engine to engine I don't know.

The closest you may come to regulations is probably the classification society testing. e.g. Lloyds ENV1,2,3 & 4, one of which is for engine mounted equipment and necessarily includes the vibration levels in terms of G forces and frequencies; equipment in the fuel lines have to contend with hydraulic pulsations (high pressure pump and injectors) and mechanical vibration.

JMW

http://www.ViscoAnalyser.com

 

[DYV1973]

Thanks for your reply, and I indeed meant the high pressure (circulation) part of the fuel system. Do you mean engine or booster module manufacturers? I have contacted both parts, but in the moment neither of them seems to have an answer (or does not want to give an answer).

Class (GL/LR) testing is only describing tests for mechanical vibrations, but my concern in the moment is for hydraulic pulsations.

So actually I am looking for some field experience about frequencies and amplitudes of hydraulic pressure pulses, most likely caused by the engine fuel injection.

 

[jmw]

No, I meant the engine manufacturers.
The booster module suppliers do not tend to have/need this information.
They usually rely on using only equipment certified (by the certification agencies) and approved (by the engine manufacturers).

However, you would expect the engine manufacturers to have this data and it's where I first acquired it some 10-12 years ago (and since lost it).
Of course, you could try any of the manufacturers of equipment for the fuel circuit, no point in passing the testing only to have the sensor fail due to hydraulic pulsations.
Or maybe the manufacturers of the injectors.

Pressure pulsations used to be a problem with mass meters (and may still be at these levels for some manufacturers) but generally sensors or equipment not containing pressure in the measuring/critical elements are mostly not directly affected. The effect of the vibrations produced ought to be covered by the class testing.

Getting engine manufacturer approvals involved 8000hrs continuous operation testing for the sensor I worked on. Any problems should show up in those tests (and tended to do so) and get identified and fixed. (And did not necessarily mean a restart of the trial).

JMW

http://www.ViscoAnalyser.com