Weapons bay thermal environment

Design and construction
  • Author
  • Message
Offline

barrelnut

Enthusiast

Enthusiast

  • Posts: 53
  • Joined: 06 Mar 2015, 00:05

Unread post07 Mar 2017, 13:04

steve2267 wrote:If they are venting the cooling air in a concentric [i]sheath[i] around the engine nozzle, that could potentially greatly reduce the IR signature of the engine.


I'm sure they are also using that air for cooling the nozzle by providing a layer of cool air between nozzle walls and the jet exhaust as described in this Lockheed-Martin patent.

Exhaust induced ejector nozzle system and method:
https://www.google.com/patents/US6295805

Image
Offline

juretrn

Senior member

Senior member

  • Posts: 420
  • Joined: 31 Jul 2016, 01:09
  • Location: Slovenia

Unread post07 Mar 2017, 13:39

With the purpose of reducing the IR signature?
Russia stronk
Offline
User avatar

sferrin

Elite 5K

Elite 5K

  • Posts: 5444
  • Joined: 22 Jul 2005, 03:23

Unread post07 Mar 2017, 14:37

juretrn wrote:With the purpose of reducing the IR signature?


For real?
"There I was. . ."
Offline
User avatar

steve2267

Elite 2K

Elite 2K

  • Posts: 2214
  • Joined: 12 Jun 2016, 17:36

Unread post07 Mar 2017, 16:23

barrelnut wrote:
steve2267 wrote:If they are venting the cooling air in a concentric [i]sheath[i] around the engine nozzle, that could potentially greatly reduce the IR signature of the engine.


I'm sure they are also using that air for cooling the nozzle by providing a layer of cool air between nozzle walls and the jet exhaust as described in this Lockheed-Martin patent.

Exhaust induced ejector nozzle system and method:
https://www.google.com/patents/US6295805

Image


I hadn't thought about something like that. In addition to reducing IR signature you will lower the temperature of the nozzle materials. You can use that temp margin for increased durability / reliability, OR by saving weight (by making the part lighter). That is pretty cool.
Take an F-16, stir in A-7, dollop of F-117, gob of F-22, dash of F/A-18, sprinkle with AV-8B, stir well + bake. Whaddya get? F-35.
Offline

juretrn

Senior member

Senior member

  • Posts: 420
  • Joined: 31 Jul 2016, 01:09
  • Location: Slovenia

Unread post08 Mar 2017, 03:00

sferrin wrote:
juretrn wrote:With the purpose of reducing the IR signature?


For real?

No need to be a d*ck about it.
Russia stronk
Offline

markithere

Enthusiast

Enthusiast

  • Posts: 65
  • Joined: 25 Mar 2009, 17:26

Unread post10 Mar 2017, 23:15

steve2267 wrote:
barrelnut wrote:
steve2267 wrote:If they are venting the cooling air in a concentric [i]sheath[i] around the engine nozzle, that could potentially greatly reduce the IR signature of the engine.


I'm sure they are also using that air for cooling the nozzle by providing a layer of cool air between nozzle walls and the jet exhaust as described in this Lockheed-Martin patent.

Exhaust induced ejector nozzle system and method:
https://www.google.com/patents/US6295805

Image


I hadn't thought about something like that. In addition to reducing IR signature you will lower the temperature of the nozzle materials. You can use that temp margin for increased durability / reliability, OR by saving weight (by making the part lighter). That is pretty cool.


Unless that air is denser than surrounding air and or much cooler it would do nothing to mask the IR signature of the exhaust. There is no difference than the air already found in the atmosphere with the entire volume of space between exhaust and IR sensor. The only advantage would be the temperature of the outside nozzle. Number 20.
Previous

Return to F-35 Design & Construction

Who is online

Users browsing this forum: No registered users and 2 guests