KJ_Lesnick
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The F-16 inlet is a mixed-compression (at least two-shocks in the duct) inlet right?
KJ_Lesnick
KJ_Lesnick
KJ_Lesnick said:Kind of odd that they managed to make a pitot-inlet work effectively at high-speed. From what I was told the F-16 had great acceleration at high-supersonic speeds,
KJ
flateric said:F-16 inlet (both 'old' "small mouth" Normal Shock Inlet (NSI) and 'new' "big mouth" Modular Common Inlet Duct (MCID)) are Normal Shock Inlets. http://www.habu2.net/vipers/viperblocks/
It's convergent divergent diffuser inlet actually.
I'm attaching some pics that can make situation more clear.
KJ_Lesnick said:The second picture appears to show multiple shock-waves, and the 4th picture shows clearly "Oblique Shock" which is a shockwave that slows flow from a supersonic to a lower, but still supersonic speed... not a normal shock which slows you down from a supersonic to a subsonic speed...
KJ_Lesnick said:-What's the ECS-inlet?
"...a thin, centerline, airfoil-shaped tension strut member
inside the cowl, which minimizes cowl deflections under load and allows a lighter
and less costly structural design. Flow quality is not affected by the strut."
KJ_Lesnick said:If the F-16's inlet was highly limited in speed, where did all that stuff I heard awhile back online about the F-16 accelerating particularly well at supersonic speed (something a typical pitot-type inlet wouldn't be able to do very well) come from? ???
Kendra Lesnick
KJ_Lesnick said:Getting good higher supersonic performance means you'll want a variable inlet ramp.
look like small mouth inlet ?F-2 inlet with a block 50 inlet. The F-2 nose drops and it had to be redesigned, supposedly optimized for the F110-IHI-129.
It’s a custom inlet, shape is similar to small but size wise it can take the extra air.look like small mouth inlet ?F-2 inlet with a block 50 inlet. The F-2 nose drops and it had to be redesigned, supposedly optimized for the F110-IHI-129.
I think F-16/79 has slightly longer splitter plate so maybe it is mixed compression inlet? but normal F-16 is internal compression?F-16 inlet (both 'old' "small mouth" Normal Shock Inlet (NSI) and 'new' "big mouth" Modular Common Inlet Duct (MCID)) are Normal Shock Inlets. http://www.habu2.net/vipers/viperblocks/
It's convergent divergent diffuser inlet actually.
I'm attaching some pics that can make situation more clear.
What is unstart?They're all going to be external compression only, to avoid unstarts (hard enough for the SR-71 in cruise, let alone a maneuvering fighter).
On a mixed compression inlet like the SR-71, there is one external oblique shock from the tip of the center cone, followed by several internal oblique shocks reflecting back an forth between the outer cowl and the inner cone before terminating in a normal shock at the narrowest portion of the air path. The multiple oblique shocks gently slow and compress the air, giving the best possible supersonic ram pressure recovery.What is unstart?They're all going to be external compression only, to avoid unstarts (hard enough for the SR-71 in cruise, let alone a maneuvering fighter).
So basically F-16, F-35, Rafale, Eurofighter , Gripen inlet are all external compression inlet to prevent the unstart phenemenon right?. How about F-100 or Mig-19 inlet? Are those two internal compression inlet?. Which one are mixed compression? F-15?As reported, the F-16 small mouth and large mouth intakes are both pitot normal shock designs.
As far as I know, the only mixed compression inlets have been the A-12/SR-71 family and the XB-70. The MiG-25/31 fly fast enough that a mixed compression inlet could be advantageous, but they appear to be variable multi-ramp external compression designs.So basically F-16, F-35, Rafale, Eurofighter , Gripen inlet are all external compression inlet to prevent the unstart phenemenon right?. How about F-100 or Mig-19 inlet? Are those two internal compression inlet?. Which one are mixed compression? F-15?As reported, the F-16 small mouth and large mouth intakes are both pitot normal shock designs.
That interesting, I have always thought that maybe the shock cone of F-16/rafale/gripen inlet are close enough to the internal that they are essentially mixed compression.As far as I know, the only mixed compression inlets have been the A-12/SR-71 family and the XB-70. The MiG-25/31 fly fast enough that a mixed compression inlet could be advantageous, but they appear to be variable multi-ramp external compression designs.So basically F-16, F-35, Rafale, Eurofighter , Gripen inlet are all external compression inlet to prevent the unstart phenemenon right?. How about F-100 or Mig-19 inlet? Are those two internal compression inlet?. Which one are mixed compression? F-15?As reported, the F-16 small mouth and large mouth intakes are both pitot normal shock designs.
I highly doubt that MiG-19 and F100 are mixed compression. They both are more likely to be pitot normal shock by appearance and their low supersonic envelope. It would be very hard to achieve mixed compression over a range of Mach numbers without some variable intake geometry. Maybe the XF8U-3 with its forward swept cowl and large inlet bypass doors, but I’m just guessing based on the projected flight Mach numbers.That interesting, I have always thought that maybe the shock cone of F-16/rafale/gripen inlet are close enough to the internal that they are essentially mixed compression.As far as I know, the only mixed compression inlets have been the A-12/SR-71 family and the XB-70. The MiG-25/31 fly fast enough that a mixed compression inlet could be advantageous, but they appear to be variable multi-ramp external compression designs.So basically F-16, F-35, Rafale, Eurofighter , Gripen inlet are all external compression inlet to prevent the unstart phenemenon right?. How about F-100 or Mig-19 inlet? Are those two internal compression inlet?. Which one are mixed compression? F-15?As reported, the F-16 small mouth and large mouth intakes are both pitot normal shock designs.
I can only think of Mig-19 and f-100 for internal compression though
I know Mig-19 and F-100 are not mixed compression, I meant, based on their look, I think only them has full internal compression ( no forward plate)I highly doubt that MiG-19 and F100 are mixed compression. They both are more likely to be pitot normal shock by appearance and their low supersonic envelope. It would be very hard to achieve mixed compression over a range of Mach numbers without some variable intake geometry. Maybe the XF8U-3 with its forward swept cowl and large inlet bypass doors, but I’m just guessing based on the projected flight Mach numbers.That interesting, I have always thought that maybe the shock cone of F-16/rafale/gripen inlet are close enough to the internal that they are essentially mixed compression.As far as I know, the only mixed compression inlets have been the A-12/SR-71 family and the XB-70. The MiG-25/31 fly fast enough that a mixed compression inlet could be advantageous, but they appear to be variable multi-ramp external compression designs.So basically F-16, F-35, Rafale, Eurofighter , Gripen inlet are all external compression inlet to prevent the unstart phenemenon right?. How about F-100 or Mig-19 inlet? Are those two internal compression inlet?. Which one are mixed compression? F-15?As reported, the F-16 small mouth and large mouth intakes are both pitot normal shock designs.
I can only think of Mig-19 and f-100 for internal compression though
I thought the splitter plate also create oblique shock to slow down the supersonic air stream?. That how f-16/rafale make their external compression right?The splitter plate is only to separate the boundary layer from the inlet when the inlet is aft of the nose. Not needed when the inlet is the front of the aircraft.
Of course, the DSI inlet on the F-35 and J-20 directs the boundary layer around the inlet opening, so no splitter plate there either.