N1 disc AI capability

[West Coast]

Recently had an icing encounter that had me wondering about engine blade icing. Rime icing on the N1 blades caused high VIB's on both engines and airframe buffeting. Cowl AI was on, but that's not not going to stop the blades from icing up. Do any engine manufacturers past or present have anti icing capability for the N1 disc? Seems to me heating them by some means would rob the engine of further by robbing more bleed and potentially raising the air temp.

Thoughts

[Monarch Man]

Hmmmm perhaps this?

"Fan Ice Removal
CAUTION: Avoid prolonged operation in moderate to severe icing conditions.
If moderate to severe icing conditions are encountered:
[RR Engines]
During flight in moderate to severe icing conditions for prolonged periods, if fan icing is suspected due to high engine vibration, the fan blades must be cleared of any ice. Perform the following procedure on both engines, one engine at a time: quickly reduce thrust to idle for 5 seconds then restore the required thrust. If vibration persists, advance thrust lever to 90% N1 momentarily.
[GE Engines]
During flight in moderate to severe icing conditions for prolonged periods with N1 settings at or below 70%, or when fan icing is suspected due to high engine vibration, the fan blades must be cleared of any ice. Perform the following procedure every 15 minutes on both engines, one engine at a time: reduce thrust toward idle then increase to a minimum of 70% N1 for 10 to 30 seconds.
Note: Operation in icing conditions may result in displayed vibration levels up to and exceeding the normal operating range. Extended operation at high vibration levels in icing conditions will not result in engine damage."

[lomapaseo]

Do any engine manufacturers past or present have anti icing capability for the N1 disc? Seems to me heating them by some means would rob the engine of further by robbing more bleed and potentially raising the air temp.



I think I understand what you asked in the first sentence, although I don't understand what you are saying in the second.

I've never heard of any means to plumb hot air to a fan blade. Not sure of why you mention a disc in your question.

The technical challenge is overwheming to prevent ice formation anywhere in the inlet fan flow environment simply due to the heat transfer/loads necessary to overcome. The current technology seeks to only limit the amount of ice build up to a point where safety of flight is not threatened. Thus, the plan is to have the ice shed itself after it builds up in small enough layers to be shed without causing problems. If the buildup is anywhere near the centerline of the engine one can always plan on some heat being driven forward up the drive shafts from the turbine area. Even a few degrees warmer can help limit the ice buildup on a fan spinner.

But for the fan blades we're just going to have to rely on mother nature and newtonian physics for the present.

[dixi188]

I believe some engines have used bleed air to anti-ice the spinner but not the blades.

IIRC the RR Spey used bleed air to anti-ice the stators in the intake.

On the ALF 502 and 507, (BAe 146 / RJ) engine oil for the reduction gearbox also provides anti-ice for the spinner.

[West Coast]

Lomaseo

Unfortunately mother nature and physics failed me and it made me curious if it had been addressed from a tech pov. Interchangeably using disc and blades, perhaps incorrectly but that was the intent.

Dixi188

Thanks, at least to some degree AI aft of the cowl and probes has been contemplated.