Question about con trials

[Brett Buck]

Hi Brett, I had always kicked around a theory of how a nuclear powered aircraft would work. I used my theory to generate some discussion among my aviation students. Using Boyle's Law, a small core reactor would heat O2 contained in a vessel, expand and regulate its expulsion to turn a free turbine attached to a gearbox driving a propeller. Some of my students suggested using liquid instead of O2. We all concluded that a conventional propeller was most practical. We also all concluded there was one major hurdle...How to replenish the O2 or liquid? It was a very stimulating conversation to say the least...and kept a few of them awake.  
Norm

   It worked with a conventional jet engine with the burners replaced with the reactor, taking air out of the compressor section, and put back into the turbine section. Sucks in air with the compressor, heats it, allows it to expand and go out the turbine. They had two versions, one that ran the air directly over the reactor core, and one that used a closed-cycle reactor cooling system and a heat exchanger.

   Same with Pluto/Tory II, - they just rammed the air in, heated it, and shot it back out.

   You *could* create a turboprop for low-speed applications using the same principle, or even a piston engine using standard steam technology. But as they found before and during WWII, with a turbo-supercharged engine, the pistons and crankshaft were just slowing it all down, and all you really needed was the supercharger/compressor and the turbocharger/turbine, and some heat source in between.

      Brett

[Howard Rush]

95% is produced from natural gas via a process called steam methane reforming.

Thanks, Dave.  We should have known that.

[Steve Thomas]

My understanding is the military flight pattern is considerably higher than the commercial flight pattern. 

If you mean cruise altitudes, most airliners start off in the low-to-mid 30s if they're heavy, winding up in the high 30s to low 40s once they're light.  Some of the military stuff is a bit lower, some a bit higher, but generally mostly about the same.

You can imagine what a PITA the whole chemtrail thing was for us in military combat jets. There we were in something where you're trying to fit in all that fuel, avionics and weaponry, while still trying to maintain a decent thrust/weight ratio and aerodynamic performance - but on top of that, we had to carry these great quantities of mind-altering chemicals, because of some enormous secret international conspiracy or something. Still, those fellas in WW2 managed it in their Spitfires and 109s and Fortresses, so if it was good enough for them, it's good enough for us. 

[Chris McMillin]

What about the reptilians!
Chris...

[Robert Dible]

Conspiracy theories abound, and the net has supercharged the effect.  JFK, moon landings, crop circles, falling towerers of 9/11, Monsanto, HARP weather modification, and yes contrails have been popular the past 50 years.  But If you think about it, people have been gaslighting others for as long as camp fires have existed.

[Brett Buck]

What about the reptilians!

  What indeed!  I hate those bastards.

     Brett

[Bill Johnson]

   For space applications," conventional" engines (like NERVA)  would be very good, and the technology is well in hand since the 60's. IT was planned for use in the mid-70's as the upper stages of the Saturn V for Mars missions and other high-performance requirements. And it's not like you are going to contaminate space, what with the billions of unshielded fusion reactors we already have. The big problem will be the nuclear chicken littles that will prevent you from launching it. They are still terrified of launching even RTGs, and this is an order of magnitude more risky. You only have to use a small shield between the spacecraft and the engine.

    The other, potentially far more capable, technology is something like ORION, which amounts to dropping mini-bombs out the back of the spacecraft and detonating them, once a second or so, and letting them push on a huge "pusher plate" with a shock absorber to isolate the crew compartment(s). The interesting thing is that idea is that the larger it is, the better it works. Some of the studies have spacecraft the size of a city block with hundreds of crew. That is far from being a practical, implementable, technology and poses legitimate concerns for where you launch such a thing. It quickly became clear that you couldn't launch it from the ground, for obvious reasons, so you are then looking at many conventional launches to assemble the thing in lunar orbit, or something like that.

     Brett

I think in the future we, or more probably our children, will see the technology put to practical use. Interplanetary missions and beyond will have to launch from space. In the mean time, I think engine efficiency / new technology to allow Single Stage To Orbit capability is our best hope for human expansion beyond the third rock from the sun.

That technology might leave some new contrails that, hopefully, won't upset some people........

[Norm Faith Jr.]

Isn't this close to being "perpetual energy / propusion?"
Norm

   It worked with a conventional jet engine with the burners replaced with the reactor, taking air out of the compressor section, and put back into the turbine section. Sucks in air with the compressor, heats it, allows it to expand and go out the turbine. They had two versions, one that ran the air directly over the reactor core, and one that used a closed-cycle reactor cooling system and a heat exchanger.

   Same with Pluto/Tory II, - they just rammed the air in, heated it, and shot it back out.

   You *could* create a turboprop for low-speed applications using the same principle, or even a piston engine using standard steam technology. But as they found before and during WWII, with a turbo-supercharged engine, the pistons and crankshaft were just slowing it all down, and all you really needed was the supercharger/compressor and the turbocharger/turbine, and some heat source in between.

      Brett

[Phil Krankowski]

Isn't this close to being "perpetual energy / propusion?"
Norm

Nope.  Any sufficiently advanced technology is indistinguishable from magic...(or a big gun) 

The energy source is radioactive decay.  Engines operate via heat.  In a simplistic sense it doesn't matter where the heat comes from as long as it is suitable in quality. 

Look at model sterling engines, "sealed" from the environment,  or any other heat cycle engine. 

Fuel provides heat more than anything else.   There is much more air mass than fuel.  Simply heating the air is enough. 

I honestly don't like the idea of a large radioactive source air born.  In space seems a little safer actually.

Phil

[Brett Buck]

Isn't this close to being "perpetual energy / propusion?"

   No. The energy was stored when the elements were formed, so no magic involved. In this case, it would eventually run down as the nuclear materials are consumed, boiled away, or are altered to non-reactive or even anti-reactive forms. The latter is the likely case, where in the course of running, the elements are transformed into material that absorbs neutrons, and effectively reduces the reactivity until it doesn't have enough power to keep going. This is called "poisoning" the reaction. This is an issue in other reactors as well.   Of course, many other failures might come into play in a mission that could last weeks or months. It wouldn't take much of a problem in the control system to cause a crash when you are blasting around at Mach 2.5 at treetop level.

     Brett

   

[Norm Faith Jr.]

I guess I took the endurance factor of the Pluto project, "weeks or months," as almost being "perpetual," in as much that it's amazing that something could run that long without being replenished. So in essence, "when it runs out of gas," what you have left is is "nuclear waste?"
Norm

   No. The energy was stored when the elements were formed, so no magic involved. In this case, it would eventually run down as the nuclear materials are consumed, boiled away, or are altered to non-reactive or even anti-reactive forms. The latter is the likely case, where in the course of running, the elements are transformed into material that absorbs neutrons, and effectively reduces the reactivity until it doesn't have enough power to keep going. This is called "poisoning" the reaction. This is an issue in other reactors as well.   Of course, many other failures might come into play in a mission that could last weeks or months. It wouldn't take much of a problem in the control system to cause a crash when you are blasting around at Mach 2.5 at treetop level.

     Brett

   

[Brett Buck]

I guess I took the endurance factor of the Pluto project, "weeks or months," as almost being "perpetual," in as much that it's amazing that something could run that long without being replenished. So in essence, "when it runs out of gas," what you have left is is "nuclear waste?"

   Pretty much, the issue of storage having been solved very neatly by flying it to the USSR, where dumping it not only allowed, but a good idea.

    Brett

[Norm Faith Jr.]

 

   Pretty much, the issue of storage having been solved very neatly by flying it to the USSR, where dumping it not only allowed, but a good idea.

    Brett