High Bypass turbofan CFM

[NPloysa]

Anyone know what a typical high bypass turbofan engine has for a CFM rating? I know I read somewhere that the GE90 or PW4400 on the B777 could suck all the air out of a 3-story house in one second, but what does that equal in CFM?



I am wondering because we (Long Tech. mechanic and I) were working on Air Handler #1 in the building today and it had a stamped flow rating of 100,000 CFM with a 200 HP 3-phase motor.



Edit: The AH at work is measured in CFM, jet engines are measured in lbs or kgs per second. The AH is at 1/2 PSI or 14 inwc, and the jet would be at pressures I am not sure of!



What do you guys think a large high bypass would flow? Like I said, I have had some of this info but lost it. I know it is HIGH!!



Thanks, Nick

 

[rbattelle]

I can give an example. A Rolls Royce Trent 892 engine (this series will power the Airbus A380 and is of the same class as a GE90-115) has an inlet air flow rate at sea-level of about 2700 lb/s at takeoff power. In CFM, that works out to 2118216 CFM at sea level. Yes, that's over 2 million CFM.



You understand, then, why gas turbines are normally spec'd in terms of mass flow rate rather than volume flow rate.

 

[NPloysa]

YEP! Thanks, I knew it was around that number. All the jet engine books I have talk about flow but I was looking for specific numbers. Appreciate it!





SO, taking my air handler specs into the equation, the air handler flows in 20 seconds what the Trent does in ONE second (20 times the flow rate).



The Trent flows 35,306 cubic feet of air per second. I wonder what the cubic footage of the museum I work at would be, estimated? Hmm... .



Nick

 

[rbattelle]

I must correct myself here... . the Trent 900 will power the A380. Trent 800 series power the A340. For those who are counting.