Hi All,

Sorry to cast the net out so wide, this maybe this is a simple problem, but it has me stumped.  BTW, not a lot of experience for me on dynamic problems in general.

I am running a Fan Blade Out (FBO) imbalance loading on a rotating shaft.  So at one end of the 3D model of the shaft I have dynamic torque, and vertical shear and over turning moment loads.  I run inertia relief, get those counter balancing accelerations, apply them, and the model runs fine.

I do the same for the static loads on the model: speed, pressure, temperature, cut boundary loads etc.  It runs fine and results match some 2D models I have.

When I try to combine them both - I can't get the job the solve.  I suspect it is that the FBO loads deflect the 5 foot long shaft about 4 inches off the engine centerline and that doesn't play well with the RPM I have applied about the centerline.  So I've added another imbalance load (which might be accounted for in the vert and moments I've been given from the System Dynamics folks here.)

I have a workaround, but just wondering if I'm missing something fundamental trying to run the two sets of loads together.

Thanks,

Dan Bohlen
Senior Engineer, Stress Analysis
STAR review chairman, military structures
NGP2 engine focal
GE Aerospace
1 Neumann Way
Evendale, OH  45215  USA

Build B90 Column  L 3.75
M/D H358  Cell  513-917-3402

Building 200  Desk Phone 3-8816

GE FOCUS:  Safety, Quality, Delivery, Cost

"In God we trust, all others bring data." W Edwards Deming

Dear Mr. Bohlen,
you mentioned cut boundary loads. Is any submodeling involved?

Best regards
Riccardo Testi

Development and Strategies
2 Wheeler Engines Technical Centre
Piaggio & C. S.p.A
Viale Rinaldo Piaggio, 25
56025 Pontedera (Pisa) - ITALY
Phone:  +39 0587 272850
Fax:        +39 0587 272010
Mobile: +39 339 7241918
E-mail:    riccardo.testi@piaggio.com

-----Original Message-----
From: Bohlen, Dan (GE Aerospace, US) dan.bohlen@ge.com
Sent: martedì 12 dicembre 2023 19:53
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: [Xansys] FW: Crowdsource: Rotor Dynamic Problem

CAUTION:This email originated from outside the Piaggio Group. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Hi All,

Sorry to cast the net out so wide, this maybe this is a simple problem, but it has me stumped.  BTW, not a lot of experience for me on dynamic problems in general.

I am running a Fan Blade Out (FBO) imbalance loading on a rotating shaft.  So at one end of the 3D model of the shaft I have dynamic torque, and vertical shear and over turning moment loads.  I run inertia relief, get those counter balancing accelerations, apply them, and the model runs fine.

I do the same for the static loads on the model: speed, pressure, temperature, cut boundary loads etc.  It runs fine and results match some 2D models I have.

When I try to combine them both - I can't get the job the solve.  I suspect it is that the FBO loads deflect the 5 foot long shaft about 4 inches off the engine centerline and that doesn't play well with the RPM I have applied about the centerline.  So I've added another imbalance load (which might be accounted for in the vert and moments I've been given from the System Dynamics folks here.)

I have a workaround, but just wondering if I'm missing something fundamental trying to run the two sets of loads together.

Thanks,

Dan Bohlen
Senior Engineer, Stress Analysis
STAR review chairman, military structures
NGP2 engine focal
GE Aerospace
1 Neumann Way
Evendale, OH  45215  USA

Build B90 Column  L 3.75
M/D H358  Cell  513-917-3402

Building 200  Desk Phone 3-8816

GE FOCUS:  Safety, Quality, Delivery, Cost

"In God we trust, all others bring data." W Edwards Deming

Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day.

Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list

Well you can think of my model as a submodel - I am applying cut forces for the static loads from a 2D system model.

-----Original Message-----
From: Testi Riccardo riccardo.testi@piaggio.com
Sent: Wednesday, December 13, 2023 2:59 AM
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: EXT: [Xansys] Re: Crowdsource: Rotor Dynamic Problem

WARNING: This email originated from outside of GE. Please validate the sender's email address before clicking on links or attachments as they may not be safe.

Dear Mr. Bohlen,
you mentioned cut boundary loads. Is any submodeling involved?

Best regards
Riccardo Testi

Development and Strategies
2 Wheeler Engines Technical Centre
Piaggio & C. S.p.A
Viale Rinaldo Piaggio, 25
56025 Pontedera (Pisa) - ITALY
Phone:  +39 0587 272850
Fax:        +39 0587 272010
Mobile: +39 339 7241918
E-mail:    riccardo.testi@piaggio.com

-----Original Message-----
From: Bohlen, Dan (GE Aerospace, US) dan.bohlen@ge.com
Sent: martedì 12 dicembre 2023 19:53
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: [Xansys] FW: Crowdsource: Rotor Dynamic Problem

CAUTION:This email originated from outside the Piaggio Group. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Hi All,

Sorry to cast the net out so wide, this maybe this is a simple problem, but it has me stumped.  BTW, not a lot of experience for me on dynamic problems in general.

I am running a Fan Blade Out (FBO) imbalance loading on a rotating shaft.  So at one end of the 3D model of the shaft I have dynamic torque, and vertical shear and over turning moment loads.  I run inertia relief, get those counter balancing accelerations, apply them, and the model runs fine.

I do the same for the static loads on the model: speed, pressure, temperature, cut boundary loads etc.  It runs fine and results match some 2D models I have.

When I try to combine them both - I can't get the job the solve.  I suspect it is that the FBO loads deflect the 5 foot long shaft about 4 inches off the engine centerline and that doesn't play well with the RPM I have applied about the centerline.  So I've added another imbalance load (which might be accounted for in the vert and moments I've been given from the System Dynamics folks here.)

I have a workaround, but just wondering if I'm missing something fundamental trying to run the two sets of loads together.

Thanks,

Dan Bohlen
Senior Engineer, Stress Analysis
STAR review chairman, military structures
NGP2 engine focal
GE Aerospace
1 Neumann Way
Evendale, OH  45215  USA

Build B90 Column  L 3.75
M/D H358  Cell  513-917-3402

Building 200  Desk Phone 3-8816

GE FOCUS:  Safety, Quality, Delivery, Cost

"In God we trust, all others bring data." W Edwards Deming

Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day.

Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list

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Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list

What does Ansys tell you when it refuses to carry out the job?
Are there any nonlinearities?

-----Original Message-----
From: Bohlen, Dan (GE, US) dan.bohlen@ge.com
Sent: mercoledì 13 dicembre 2023 14:09
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: [Xansys] Re: Crowdsource: Rotor Dynamic Problem

CAUTION:This email originated from outside the Piaggio Group. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Well you can think of my model as a submodel - I am applying cut forces for the static loads from a 2D system model.

-----Original Message-----
From: Testi Riccardo riccardo.testi@piaggio.com
Sent: Wednesday, December 13, 2023 2:59 AM
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: EXT: [Xansys] Re: Crowdsource: Rotor Dynamic Problem

WARNING: This email originated from outside of GE. Please validate the sender's email address before clicking on links or attachments as they may not be safe.

Dear Mr. Bohlen,
you mentioned cut boundary loads. Is any submodeling involved?

Best regards
Riccardo Testi

Development and Strategies
2 Wheeler Engines Technical Centre
Piaggio & C. S.p.A
Viale Rinaldo Piaggio, 25
56025 Pontedera (Pisa) - ITALY
Phone:  +39 0587 272850
Fax:        +39 0587 272010
Mobile: +39 339 7241918
E-mail:    riccardo.testi@piaggio.com

-----Original Message-----
From: Bohlen, Dan (GE Aerospace, US) dan.bohlen@ge.com
Sent: martedì 12 dicembre 2023 19:53
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Subject: [Xansys] FW: Crowdsource: Rotor Dynamic Problem

CAUTION:This email originated from outside the Piaggio Group. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Hi All,

Sorry to cast the net out so wide, this maybe this is a simple problem, but it has me stumped.  BTW, not a lot of experience for me on dynamic problems in general.

I am running a Fan Blade Out (FBO) imbalance loading on a rotating shaft.  So at one end of the 3D model of the shaft I have dynamic torque, and vertical shear and over turning moment loads.  I run inertia relief, get those counter balancing accelerations, apply them, and the model runs fine.

I do the same for the static loads on the model: speed, pressure, temperature, cut boundary loads etc.  It runs fine and results match some 2D models I have.

When I try to combine them both - I can't get the job the solve.  I suspect it is that the FBO loads deflect the 5 foot long shaft about 4 inches off the engine centerline and that doesn't play well with the RPM I have applied about the centerline.  So I've added another imbalance load (which might be accounted for in the vert and moments I've been given from the System Dynamics folks here.)

I have a workaround, but just wondering if I'm missing something fundamental trying to run the two sets of loads together.

Thanks,

Dan Bohlen
Senior Engineer, Stress Analysis
STAR review chairman, military structures
NGP2 engine focal
GE Aerospace
1 Neumann Way
Evendale, OH  45215  USA

Build B90 Column  L 3.75
M/D H358  Cell  513-917-3402

Building 200  Desk Phone 3-8816

GE FOCUS:  Safety, Quality, Delivery, Cost

"In God we trust, all others bring data." W Edwards Deming

Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day.

Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list

Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day.

Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list _______________________________________________
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day.

Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list