3 ms·

Is Nozzle design actually a method of determining Solid/Liquid? I know that the design depends on expected stage of flight use and things like exhaust velocity

Is Nozzle design actually a method of determining Solid/Liquid? I know that the design depends on expected stage of flight use and things like exhaust velocity, but i didn't think just seeing a nozzle would be enough to make a determination,

sandworm101 6y ago
(1) Relative size. Solid fuel is much more energy dense. In this case, if the nozzle was for liquid then its tank is so small that it would burn out very quickly. So it is likely an SRB. Note the other nozzles for the relatively wider center tank. (2) Shape. You can look to the shape of the nozzle to see which altitude it is optimized for. SRBs are generally optimized for lower altitude. (3) Throat diameter. By following the shape of the nozzle towards the tank above you can estimate the throat. SRBs have wider throats. (4) Gimble (not seen here) SRBs can be steerable but they don't 'gimble' the same as liquid engines. Their nozzles are moved rather than the whole engine (see shuttle). So any moving nozzle bits suggests an SRB. So ya, there is much to read from just the nozzle. In fact deep in the CIA there are probably some experts with magnifying glasses studying pictures of a North Korean rocket nozzle doing exactly that.
- NikolaeVarius 6y ago
  1) I think relative size is a bit of a crapshoot. The size of the strap-ons is effectively the same size as the center core, The second stage of the core makes it look like a full sized LOX/LH2 tank because its painted orange, but it isn't. 2-3) Sure, but that is a general principal, not a sure sign its an SRB. 4) I don't see a sign of a gimbal. It may actually not even be a nozzle, and just the skirt.
  - sandworm101 6y ago
    Relative size of nozzles to attached tank. The sides are much much larger in proportion to their tanks. SLBMs (ie SRBs) https://upload.wikimedia.org/wikipedia/commons/6/6a/SLBM_Comparison.jpg https://upload.wikimedia.org/wikipedia/commons/6/6a/SLBM_Com... Atlas missile (liquid fuel) https://en.wikipedia.org/wiki/File:Atlas_2E_Ballistic_Missile.jpg https://en.wikipedia.org/wiki/File:Atlas_2E_Ballistic_Missil...

sandworm101 6y ago

(1) Relative size. Solid fuel is much more energy dense. In this case, if the nozzle was for liquid then its tank is so small that it would burn out very quickly. So it is likely an SRB. Note the other nozzles for the relatively wider center tank. (2) Shape. You can look to the shape of the nozzle to see which altitude it is optimized for. SRBs are generally optimized for lower altitude. (3) Throat diameter. By following the shape of the nozzle towards the tank above you can estimate the throat. SRBs have wider throats. (4) Gimble (not seen here) SRBs can be steerable but they don't 'gimble' the same as liquid engines. Their nozzles are moved rather than the whole engine (see shuttle). So any moving nozzle bits suggests an SRB. So ya, there is much to read from just the nozzle. In fact deep in the CIA there are probably some experts with magnifying glasses studying pictures of a North Korean rocket nozzle doing exactly that.

NikolaeVarius 6y ago
1) I think relative size is a bit of a crapshoot. The size of the strap-ons is effectively the same size as the center core, The second stage of the core makes it look like a full sized LOX/LH2 tank because its painted orange, but it isn't. 2-3) Sure, but that is a general principal, not a sure sign its an SRB. 4) I don't see a sign of a gimbal. It may actually not even be a nozzle, and just the skirt.
- sandworm101 6y ago
  Relative size of nozzles to attached tank. The sides are much much larger in proportion to their tanks. SLBMs (ie SRBs) https://upload.wikimedia.org/wikipedia/commons/6/6a/SLBM_Comparison.jpg https://upload.wikimedia.org/wikipedia/commons/6/6a/SLBM_Com... Atlas missile (liquid fuel) https://en.wikipedia.org/wiki/File:Atlas_2E_Ballistic_Missile.jpg https://en.wikipedia.org/wiki/File:Atlas_2E_Ballistic_Missil...