From: muratlanne@gmail.com   
      
   "Richard Smith"  wrote in message news:m1cy525s3b.fsf@void.com...   
      
   This is what I was hoping for.   
   I think I see it now.   
      
   May I run my "take" on it past you, testing it in every which way...?   
      
   From this ramjet engine with a nuclear power-plant in the middle heating   
   the air (no mass-rate, but is a heat-rate):   
      
   the exit/exhaust cone is bigger than the inlet cone - hence the sum of   
   forces is nett in the "progression" direction.   
      
   the reason the exit cone is bigger is that, keeping the same pressure   
   but now with thermal energy from the supplied heat (think gas laws,   
   models of bouncing/recoiling gas atoms/molecules, etc.)...  To keep   
   fairly much the same pressure profile as the inlet cone the exhaust cone   
   has to be bigger in expanding the gas to a bigger volume - to get it   
   "down to the same pressure" (as the corresponding place in the inlet   
   cone).   
      
   I will go try read the article.   
      
   Sorry I am on the tail-end of a "winter 'lurghi'" (we have a 'lurghi'   
   season here in Britain where by February people often feel like daubing   
   a red cross on their front door and giving-up) - sorry brain still   
   fuzzy.   
      
   ----------------------------------------------   
   Among the long German words I had to learn was spring fever's equivalent,   
   Fruhjahrsmudigkeit.   
      
   That explanation makes sense to me, but much in fluid dynamics doesn't such   
   as L/D and the low drag of rounded leading edges, as on torpedoes and the   
   Mach 25 Space Shuttle.  I especially don't trust extrapolating subsonic to   
   supersonic shock wave flow in the ram jet intake. I still struggle with   
   nozzle discharge coefficient and machine them by cut-and-try. It's only a   
   hobby interest to me, my paid work in aerospace was communications.   
      
   https://en.wikipedia.org/wiki/Richard_T._Whitcomb   
   "Using intuition rather than mathematics, he built a two-foot (0.6-meter)   
   chord wing section and tested it repeatedly in the Langley high-speed wind   
   tunnel, adding (with auto body putty) or removing (with a file and   
   sandpaper) material until the desired flows were achieved."   
      
   My ability to accurately visualize physics doesn't approach that level.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)