Jet engines - why thrust decreases with speed
Hi all,
Can anyone explain this:
" The thrust will decrease with an increase in speed"
1. any increase in forward airspeed will compress the air at the intake, which will lead to a larger MASS flow per unit volume. So mass flow increases with speed increase.
2. Due to intake momentum lag, air looses momentum, which decreases the overall thrust of the engine. But if air is slowed down, does the static pressure not increase and does static pressure increase not mean denser air ( this is where I might get this wrong)
Anyway, then my notes just state that increase in speed means reduction in thrust which seems to negate no. 1 above.
Can anyone shed some light on this for me, I would be very grateful.
Cheers
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