Thank you for additional information. I was not100 percent certain if that was the case especially when you have to use frequency spectrum to determine engine vibration sources. Theory and practice are sometime not exact...
This is typical two shaft turbofan engine. The only 3 shaft engine i know are the RB211, and Trent engines. This one is a two spool engine. I have worked on some minor design on the the ITrent though.
The broadband frequency was not accurately described once the frequency spectrum was...
Thanks,
Hard to say at this point...the sampling rate is sufficient for the required frequency range but requested to have those check out.
This is on OEM accelerometers on top of the casing at the front bearing position of the turbofan engine. The machine speed is accurate on these FAA...
I was trying to determine if a set or frequencies and amplitude peaks corresponds to rotor out of balance. However, there is a 13% error on one of frequency peak.
Can anyone with more experience in using accellerometers elaborate on frequency measurement error of accellerometers...I would would...
Thank you so far for the reply...I understand the blade passing frequencies...more interested in vibration source that can cause significant level of vibrations that is out of the ordinary or something typical to large fans...for example would tip clearance (a local inferfection due to asymetric...
A question arised about broadband frequency noise and vibration induced by a gas turbine engine Fan. I have some experience doing some analysis on vibration caused by interaction between static and rotating components but no experience at all on the sort of vibration that may arise from unsteady...
Probably location of the center of gravity of the whole thing relative to a location - pedestal.
You might also need to correct for tooling error by taking several reading before correcting for unbalance at two planes.
Usually, you index the part 180 degrees for the second reading to...
Interesting forum. I would have thought the results would be meaningless unless you related it to an actual experimental data.
When we do blade vibration test we can scale the normalize modal stress result to actual results to determine the maximum stress on the structure for a particular mode...
