Kronach-Lorin Ramjet

[KJ_Lesnick]

I'm curious about a couple of things: I've done some searching online and I've found a little bit about the engine, and this is what I know

• Engine was test-run in 1944
  
• It had a wire-mesh basket which rotated, feeding fine grain coal into the airflow path
  
• It had a primary and auxiliary inlet duct
  
• It used gas-bottles, which would use igniters to produce a stream of burning gas, which would be fired into the coal basket
  
• The auxiliary inlet fed clean air, which would mix under high pressure with the primary exhaust
  
• It became effective at 200 mph
  
• It had an endurance of 45 minutes
  

This may seem like a pretty comprehensive description, except for two major details

The first has to do with the 200 mph speed at which it became effective, what I'm unsure of is the exact specifics

• I assume that the design would be able to produce stable combustion, that's pretty obvious
  
• I wouldn't be surprised if it would produce positive thrust (more than the drag of the ramjet assembly)
  
• I'm unsure if this would produce more drag than the inlet and aircraft together: It wouldn't surprise me if it did admittedly, as it does seem to be implied.
  
• What I'm really curious about is whether the design will produce sufficient acceleration to go from 200 mph all the way through Mach 1 (without rocket assistance), and then right on up to Mach 2.6 (design speed), and in a reasonable amount of time.
  

This, in and of itself, is highly impressive: Most ramjets designed for supersonic speed seem to be highly inefficient at subsonic speeds in terms of overall power and fuel burn: This design looked like it had the ability to operate across a wide range of speeds and appeared to possess a decent endurance.

The second has to do with the subject of fuel: Though the design was configured to use coal, I'm curious if a similar concept could have been adapted to use regular fuels, with the fuel being sprayed in to the combustion chamber, pressurized gas-bottles used to produce massive flames which would serve to produce both an ignition source and possibly a propulsive source.

[wuzak]

I guess it used coal because that's the fuel the Germans had in abundnace at that stage of the war.

You might get better performance with regular petrol or Diesel, but what point is that if you haven't enough to put in the plane.

http://tanks45.tripod.com/Jets45/Histories/Do17/Do17.htm

FWIW, the GErmans were developing a couple of aviation steam turbines for use with the Me 264. One was to have 4,000hp and the other 6,000hp. The latter was planned to use 70% pulverised coal/30% liquid fuel at least until liquid fuel supplies improved.

[KJ_Lesnick]

I guess it used coal because that's the fuel the Germans had in abundnace at that stage of the war.

No, I get that -- I'm just curious if the basic mechanism would work if gas was used