747400sp From United States of America, joined Aug 2003, 4061 posts, RR: 2 Posted (9 years 11 months 1 week 9 hours ago) and read 5976 times:
I just fond out that the CFM 56 was build from the tech of this engine. Now I know the only plane that use the F101 is the B-1 bomber. I know the cfm 56 fan diameter ranges from cfm 56-2 68 inches,-3 60 inches,-5a,b 68 inches and -7 61 inches. But want the pure GE F101 diameter.
PS By the way how can a loud engine like the F101 be the bases for a quiet engines like the cfm 56.
Quoting 747400sp (Thread starter): PS By the way how can a loud engine like the F101 be the bases for a quiet engines like the cfm 56.
An engine like the F101 has a high exhaust velocity which is a large contributor to noise. The shearing of the high-speed exhaust flow with the lower speed freestream causes that ripping sound known as jet noise. In higher bypass ratio engines like the CFM56, a larger portion of the energy in the high-speed exhaust is captured by the low pressure turbines thus lowering its velocity a greater degree. The jet noise is much less pronounced. In these engines other kinds of noise are noticible like buzzsaw noise caused by the fan blades and shock cell noise caused by shockwaves in the exahaust flow.