Effects of Propeller not central in Hub

[BrianBT]

We have a large azimuth tunnerl thruster which has the hub non central with the nozzle. This by some degree. The equipment supplier tells us this is not a problem

Its about 2M Dia rotation speed c 900RPM

I am concerned with hydrodynamic imbalance and fatigue. Can anyone offer advice or guidance

 

[chief]

Check the vibration characteristics of the surrounding hull and thruster foundation against another at various load settings. This will give you some parameters to discuss with the equipment supplier or builder/installer.

Offshore Engineering&Design

 

[BrianBT]

Thanks, its a good idea

The problem is that we are still in the new build process and have the ability to go back into drydock to remove the thruster. Once on trials the thruster supplier can walk away (as they generally do).
Class are making all the wrong noises, for reasons I am sure you are aware, so we cannot fall back on them

I am looking for research or knowledge of a failure due to a similar fault.

 

[chief]

If it is not installed correctly, do not sign off on it. Insist on correct installation as to specifications. Refer to the installatin drawings. Do not be bullied into agreeing to something that is not correct. That is why we are paid the big bucks to make the big decisions.

Offshore Engineering&Design