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Old 18th Feb 2008, 19:35
  #37 (permalink)  
bsieker
 
Join Date: Jul 2007
Location: Germany
Posts: 533
Originally Posted by Pinkman
How can you tell if cavitation has occurred post event? Does it actually physically damage the HP rotor/vanes? I thought that once the pressure had been equalised the cavitation stopped and flow resumed?
(To correct a possible misunderstanding first: this is about the high-pressure fuel pump, not the HP rotor of the engine proper.)

Cavitation is the formation and subsequent collapse of small cavities (fuel vapor, dissolved air, ...) in a liquid due to low pressure, e. g. on the suction side of a pump. The collaps can be so violent that it damages the material. It is one of the limiting factors in the design of ship propellers.

does the engine management software also limit the differential thrust between the engines.
The aircraft is designed to handle TOGA power on one engine and zero thrust (shut down/windmilling) on the other. The rudder will compensate. Also, the engine management of each engine is independent of the other.

Would be quite interesting during an engine failure at takeoff or go-around, when the computer would limit the other engine, too, depriving the aircraft of full power when it most needs it.

You can see what I am getting at - the seven second difference - could it be that the right engine was starved and the left engine reduced to match, under some limiting algorithm, independant of commands from the autothrottle.
No. On the contrary, the autothrottle, trying to maintain speed, would increase thrust on the other engine to compensate for the failed one.


Bernd
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