Author Topic: Role of NTR/BNTR/NEP in future architectures  (Read 168952 times)

Offline simonbp

RE: Role of NTR/BNTR/NEP in future architectures
« Reply #20 on: 12/31/2005 08:09 PM »
As the son of test facility engineer, They'll Find A Way....

MSFC right now has a test facility consisting of a NTP engine with large heaing coils instead of fuel rods; thus allowing thermal testing without the pesky hard radiation. The new ESAS document released contains a reference to building a closed-loop testing stand in Nevada, which shouldn't be to hard considering the best thing to make it closed-loop (a vacuum chamber) is the same enviroment in which the rocket will be operating...

Also, as far as exhaust radiation, I recall an interview with a Glenn researcher who said that current NTP designs would release just about 2-4 rads over their 360-minute burn times (a dental x-ray is about 0.5 rad)....

Simon ;)

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #21 on: 12/31/2005 08:54 PM »
Quote
simonbp - 31/12/2005  3:09 PM

As the son of test facility engineer, They'll Find A Way....

MSFC right now has a test facility consisting of a NTP engine with large heaing coils instead of fuel rods; thus allowing thermal testing without the pesky hard radiation. The new ESAS document released contains a reference to building a closed-loop testing stand in Nevada, which shouldn't be to hard considering the best thing to make it closed-loop (a vacuum chamber) is the same enviroment in which the rocket will be operating...

Simon ;)

I'm sorry, Simon, but the MSFC facility to which you refer is not a nuclear thermal test facility.  It is a small (100 kW thermal) electrically heated, heat-pipe cooled simulated reactor core.  The NTR engine in those documents is 335,000 kW thermal, and has a core power density of 5 MW/liter.  Even assuming you could match the core power density requirements, that is a factor of 3350:1 in the total power requirement.  To simply simulate the thermal power alone of the core would probably require dimming most of the lights in Huntsville, where you live.  Also, the key thing to test for in a nuclear reactor is its kinetics---how does it respond to transients, etc.  Even if you could do the testing with electrical heating, it would only be a static simulation, since electrical power systems can't change their power outputs by orders of magnitude in a fraction of a second, like a nuclear reactor can.  The closed-loop chamber referred to in the ESAS report also is NOT a vacuum chamber, but rather requires the engine to exhaust to a significant backpressure (~30 psi) in order to drive the effulent through the filters.  As I noted in the previous post, this will severely compromise the heat transfer, turbopump power, chamber pressure, and nuclear response of the system.  Even if we were allowed to exhaust into a vacuum chamber, such chambers don't stay vacuum very long when you're blowing 15,000 lbs of thrust of hydrogen into them.

Testing is a real problem, and I have read nothing in the ESAS document that allays my concerns.  MSFC has never tested a nuclear thermal engine, and it is not going to be like any engine they have ever tested before.

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #22 on: 01/01/2006 03:21 PM »
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Davros - 30/12/2005  5:07 PM

I'd be in favor of this drive but the risk of enviormentalists trying to bring down the program makes me concerned about potential project cancellation. Is there a solution to this, such as a different holding and launch site for the nuclear element of the propulsion?

There is definitely going to need to be a significant effort in educating the public further about nuclear power, and it would probably be best to begin by not lumping all things nuclear together, and followed by a healthy amount of apologies for the last sixty years of nuclear mistakes.  Open air testing of nuclear weapons, the drive of the AEC to produce weapons-grade plutonium and highly-enriched uranium at the exclusion of all else during the 50s and 60s, which has led to contamination problems in Washington and Colorado that persist to this day--these are examples of mistakes that need to be admitted.  The list could then continue with apologies for never developing a true management plan for high-level nuclear waste and the consequences of our wasteful approach to nuclear fuels, where less than 1% of the potential nuclear energy is extracted...you get the idea.

But I am firmly convinced that there are forms of nuclear energy that are very safe and efficient, even if we aren't currently exploring those forms.  That is why I am excited about the possibilities of space nuclear power, because if we are intelligent, we can do it RIGHT this time, and then apply what we learn to the nuclear problems on Earth.  One of the great things about a space system is that you put a premium on low mass, efficiency, self-reliance, and simplicity.  These requirements, if adhered to, will point towards very safe nuclear systems that do their job with a minimum of involvement.

The choice between a nuclear-electric system and a nuclear thermal system is significant.  One of the biggest distinguishing factors is the sheer power level involved.  A nuclear thermal system ranges in power level from 100s of megawatts to gigawatts of thermal power.  Indeed, the single largest nuclear reactor (in power rating) of ANY type was one of the NERVA cores tested in the 1960s, which had a core power rating of 5 gigawatts, thermal.  A reactor intended for nuclear-electric use, on the other hand, tends to be MUCH smaller.  The cores considered for robotic missions had core power ratings of hundreds of kilowatts, whereas a manned mission such as the one shown in the picture would have a core power of about 20 megawatts, thermal.  Not only are such reactors so much smaller, but they are contained reactors with no expectation for exhaust, unlike the nuclear thermal rocket.  They run in the same mode throughout the profile and do not attempt to switch modes between an open-cycle, hydrogen-cooled system to a closed-cycle, gas-cooled system.  Even after examining these documents, I'm still very unclear how they plan to do this.

I hope it is fairly well-known that a reactor that has not been operated has essentially no radioactivity at launch.  The uranium fuel of the reactor has a tremendously long half-life, in the billions of years, which means its activity (radiation emission) is incredibly small.  You can literally hold uranium fuel in your hands--you might want to wear gloves, but the dead skin in your hands will stop the small amount of (alpha-particle) radiation emission.  After the reactor reaches space and has been operated for a period of time, fission products (the result of fission) will build up.  They have very short half-lives and high activity.  Almost all the radiation emitted from a reactor comes from the decay of these fission products.  So fear of radiation during launch is not a big concern for a reactor.  Fear of the reactor falling in the water and going critical is.  Note that even in this scenario, a poorly designed reactor that fell in the water and went critical would not explode like a bomb....not even close.  It would boil some water and a small steam explosion would disassemble it.  The process would happen so fast that there would be very little time for any fission products to form and any significant radioactivity to be released.  The problem would be finding the pieces of the reactor on the bottom of the ocean.  Note that that was for a poorly-designed reactor--we must design reactors that do not go critical in a submersion launch accident.

So these are the types of information we need to tell the public about space nuclear power, in order to help them understand the risks and opportunities, and help them to understand how and why we should be doing this.

Offline Rocket Nut

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #23 on: 01/01/2006 08:45 PM »
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vanilla - 1/1/2006  11:21 AM


There is definitely going to need to be a significant effort in educating the public further about nuclear power, and it would probably be best to begin by not lumping all things nuclear together, and followed by a healthy amount of apologies for the last sixty years of nuclear mistakes.  Open air testing of nuclear weapons, the drive of the AEC to produce weapons-grade plutonium and highly-enriched uranium at the exclusion of all else during the 50s and 60s, which has led to contamination problems in Washington and Colorado that persist to this day--these are examples of mistakes that need to be admitted.  The list could then continue with apologies for never developing a true management plan for high-level nuclear waste and the consequences of our wasteful approach to nuclear fuels, where less than 1% of the potential nuclear energy is extracted...you get the idea.

I guess I don't understand your need for mea culpa and apology.  We know a lot more than we did then.  Heck, I flew through nuclear clouds within minutes of detonation to bring back samples for analysis...we thought the radiation doses we got then were "safe".  We certainly know better now, but nobody owes me an apology or any compensation.  

Can't we just use the knowledge we have developed since the 50s and move on from here?

I certainly agree with your comments about educating the public.  We have made a lot of progress since the 50s and 60s and should use the knowledge we have gained from years of research and move forward.

Regards,

Larry

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #24 on: 01/01/2006 09:30 PM »
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Rocket Nut - 1/1/2006  3:45 PM
I guess I don't understand your need for mea culpa and apology.  We know a lot more than we did then.  Heck, I flew through nuclear clouds within minutes of detonation to bring back samples for analysis...we thought the radiation doses we got then were "safe".  We certainly know better now, but nobody owes me an apology or any compensation.  

On the contrary, you are precisely the type of person I believe deserves an apology.  I do not know if you have suffered from cancer in your lifetime, but if you have or do, will you not wonder if your exposures had something to do with it?

Offline Flightstar

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #25 on: 01/01/2006 11:38 PM »
It is very important to note that nuclear options make for immediate diversity for power requirements, not only for propulsion and MTV power (I refer to Langley's comment about dualability), but for potential sustained energy at the target outpost. I gained an impression from the ESAS report that this dual target approach, alongside that of exploitation of Lunar, for example, resourses on more convential means, is what is being evaluated as the favored option for Mars transit.

Nuclear is still taboo for reasons rightly noted by vanilla, but given options presented, supporting this evalution stage and system intergration evaluation stage, appears to make sense to me.

Proceedures are much tighter than they have been previously, also.

Offline Rocket Nut

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #26 on: 01/02/2006 12:01 AM »
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vanilla - 1/1/2006  5:30 PM

Quote
Rocket Nut - 1/1/2006  3:45 PM
I guess I don't understand your need for mea culpa and apology.  We know a lot more than we did then.  Heck, I flew through nuclear clouds within minutes of detonation to bring back samples for analysis...we thought the radiation doses we got then were "safe".  We certainly know better now, but nobody owes me an apology or any compensation.  

On the contrary, you are precisely the type of person I believe deserves an apology.  I do not know if you have suffered from cancer in your lifetime, but if you have or do, will you not wonder if your exposures had something to do with it?

No, that is my point.  I was one who was directly harmed by those unrecognized dangers.  We were briefed on the known dangers at the time.  They didn't lie to us, they really thought we were being exposed to acceptable minimal doses of radiation.  We knew there was a risk.  We volunteered for the missions based on the perceived risk as it was known at the time.  In my opinion, nobody owes me anything because they and we acted upon the knowledge base that existed at the time.

We have learned so much since then that, in my opinion, we can and should move forward and not waste time apologizing for not understanding all the dangers that existed in decades past.   Learn from past mistakes, but don't dwell on those mistakes.  I worked with many scientists at Los Alamos and Lawrence Livermore Labs who were studying the effects of radiation exposure at that time.  I spent many hours in their scintillation chambers while they studied the effects of radiation on me and others who were flying the same missions.  Those scintillation chambers are a whole 'nother story, far more scary than flying through nuclear clouds.  We knew there were risks, just not how bad they were.

Just for the record, we were fairly well protected from Alpha and Beta radiation...maybe I'll scan some pictures taken in the 60s.  We were enclosed in heavy clothing from head to toe with tape covering the space between sleeves and gloves, etc.  We also passed through high volume showers on the way from the plane to the debriefing room.  (hah, the TSA has nothing on us...after the showers there were a lot of naked men standing with arms outstretched while they waved geiger-counters over us...kind of like airports here)...ah, the good old days...  Of course, the full pressure suit was also a great barrier to Alpha and Beta.

I guess I'm just being pragmatic about this.  Whenever the Government "apologizes" for anything, it costs millions or billions to support all the lawyers who swoop down on the "victims".  And yes, I would probably be one of those "victims".  I would rather that money be available for the space program.

I'm not trying to be argumentative...this is just my opinion...worth maybe 2 cents...

Regards,

Larry

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #27 on: 01/02/2006 01:44 AM »
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Rocket Nut - 1/1/2006  7:01 PM
I guess I'm just being pragmatic about this.  Whenever the Government "apologizes" for anything, it costs millions or billions to support all the lawyers who swoop down on the "victims".  And yes, I would probably be one of those "victims".  I would rather that money be available for the space program.

Very well, and I want you to know I have tremendous respect for the sacrifices you have personally made (and may yet make) for our country.  The point I was trying to make, and in retrospect realize that I did not make very well, is that for nuclear energy to be accepted in the future, I am personally of the opinion that there must be some degree of apology and admittance of past errors.  I think this step is essential in re/gaining the public's trust.  For decades we have said something that is basically not true--that nuclear power is as safe as it can be.  As a nuclear engineer, I can personally state that this is not a fact.  There are better--much better and safer ways to do nuclear power, that ironically are SAFER, SIMPLER, MORE EFFICIENT, and MORE ECONOMICAL than how we do it today.  The fact that we are not pursuing these options has little to do with safety or economics and had more to do with politics and bureaucratic inertia.  I feel passionate about the possibilities of space nuclear power because I believe this a mechanism to break out of our current nuclear stagnation.  I do not believe that reactor manufacturers will do it.  I do not believe that the Department of Energy or Naval Reactors will do it.  I hope that NASA might do it, but the Prometheus experience is not promising.

At this tenuous time, the answer (again in my opinion) is not to passively accept the 40-year old answer (NTR) that once again has been blessed as the path forward, but to push for the right solutions that have terrestrial benefit.  Do you know how many times they have decided to do nuclear thermal propulsion only to quit when they got into the real costs and diminished benefits of the technology?  Oh this would be time number 3 or 4.   Why do we think this will be any different?  If Griffin and his crew haven't solved any of the basic problems of NTR--and rather are pushing BNTR, which is substantially worse--then why do we think the result will change?

The nation, now more than ever, needs safe and economical sources of power.  The space nuclear program can be a catalyst to developing those forms of power, but the current push towards NTR will be little more than several more billion dollars wasted on testing and fuel forms that have no terrestrial benefit.  At the end of the process, they will say "nuclear" is too difficult, we give up.   Rather, let us assert a different vision for space nuclear development that can be built, can be tested, is reasonable, and has terrestrial benefit.  Our time is running out.

Offline realtime

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #28 on: 01/02/2006 05:42 AM »
Well, that was painful, yet strangely depressing.  Thank you for this thread.


Offline FransonUK

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #29 on: 01/02/2006 10:02 AM »
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Rocket Nut - 1/1/2006  3:45 PM

I guess I don't understand your need for mea culpa and apology.  We know a lot more than we did then.  Heck, I flew through nuclear clouds within minutes of detonation to bring back samples for analysis...we thought the radiation doses we got then were "safe".  We certainly know better now, but nobody owes me an apology or any compensation.  

Regards,

Larry

I think that makes you a great person.

Too many people play it safe, live like a hermit and never do anything with their lives then fall down the stairs one day and break their necks.

There's risks everywhere. I was on the tube and took the train which was 10 minutes before the one Al Queda blew up. Makes you realise there's no point playing it safe, cause you never know.

I think you've more than done something great and exciting with your life and we shouldn't be moaning about what risks were taken, cause you'll outlive a lot of those people who eat nothing but fruit and veg, give loads of money to Greenpeace, eat Dophin friendly tuna, and never fly on a plane "cause they sometimes crash you know" ;)
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Offline SimonShuttle

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #30 on: 01/02/2006 10:11 AM »
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vanilla - 1/1/2006  8:44 PM

The nation, now more than ever, needs safe and economical sources of power.  The space nuclear program can be a catalyst to developing those forms of power, but the current push towards NTR will be little more than several more billion dollars wasted on testing and fuel forms that have no terrestrial benefit.  At the end of the process, they will say "nuclear" is too difficult, we give up.   Rather, let us assert a different vision for space nuclear development that can be built, can be tested, is reasonable, and has terrestrial benefit.  Our time is running out.

But isn't the space nuclear program designed for space travel, not terrestrial benefit? Why does there have to be a clause for this to be for terrestrial benefit? That I don't understand.

More over, can you give ideals on alternatives that are on the table that the general public might not be aware of.

Interesting thread!

Offline SimonShuttle

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #31 on: 01/02/2006 10:12 AM »
Quote
vanilla - 1/1/2006  8:44 PM

Quote
Rocket Nut - 1/1/2006  7:01 PM
I guess I'm just being pragmatic about this.  Whenever the Government "apologizes" for anything, it costs millions or billions to support all the lawyers who swoop down on the "victims".  And yes, I would probably be one of those "victims".  I would rather that money be available for the space program.

Top man.

Offline FransonUK

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #32 on: 01/02/2006 10:19 AM »
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SimonShuttle - 2/1/2006  5:12 AM

Quote
Rocket Nut - 1/1/2006  7:01 PM
I guess I'm just being pragmatic about this.  Whenever the Government "apologizes" for anything, it costs millions or billions to support all the lawyers who swoop down on the "victims".  And yes, I would probably be one of those "victims".  I would rather that money be available for the space program.

Top man.

This is the trap society is falling into.

I'm a lawyer (or soliciter as we're called in the UK) and there's a huge influx of law degrees graduates now finding jobs at accident insurance claim firms, where the whole world of rightful compansation is being turned on to its head.

Companies and governments simply aren't going to be taking an risks anymore, with violent schoolkids who attack their teachers getting huge compansation when the teacher clips them over the ear. Where window cleaners get huge compansation for falling off the third run of their ladder when it's wet.

I'm totally against this, despite the possibilities for lawyers to make fast money, as it's draining the talent of law into a level of call centers and robots pushing claim buttons on their PCs. That's not law.

If we had more people like Rocket Nut then maybe we'd take some risks and advance. The other way is to become a liberal society of people who wrap themselves up in cotton wool resulting in us never advancing.

For that very reason I hope the "Nuclear, doesn't sound very safe to me" thinkers never sway the current, best way, to get this job for Mars done.
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Offline Hotol

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #33 on: 01/02/2006 10:37 AM »
No harm in a bit of an armisist view on this. Push for the current best option while using that as a motivation to finding a better, safer, cheaper option.

Scientists shouldn't complain unless they have a viable alternative in the pipeline.

Offline Rob in KC

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #34 on: 01/02/2006 03:29 PM »
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Hotol - 2/1/2006  5:37 AM

No harm in a bit of an armisist view on this. Push for the current best option while using that as a motivation to finding a better, safer, cheaper option.

Scientists shouldn't complain unless they have a viable alternative in the pipeline.

No argument from me there.

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #35 on: 01/02/2006 04:19 PM »
Quote
SimonShuttle - 2/1/2006  5:11 AM
But isn't the space nuclear program designed for space travel, not terrestrial benefit? Why does there have to be a clause for this to be for terrestrial benefit? That I don't understand.

More over, can you give ideals on alternatives that are on the table that the general public might not be aware of.

NASA seems to be very fond of touting the "spinoffs" of space technology as a primary reason for space exploration...so why should there not be direct benefit from a space nuclear program?  Heaven knows we need the energy!

I read a book a few years ago that completely reshaped what I thought I knew about nuclear energy.  It was written in 1958 and was called "Fluid Fuel Reactors".  Before I read this book I hadn't even imagined that reactors could be built in any other way than using solid fuels.  And if they were, I thought, it must be some incredibly exotic system that operated at such high temperatures that no realistic material could contain it.  Much to my surprise, I found in reading this book that there were a number of uranium compounds that could be liquid at relatively reasonable temperatures.  Indeed, there were actually three totally different approaches to reactor design outlined in this book, all of them with the goal of building a thorium-fueled thermal breeder reactor.

One technique was to dissolve uranium sulfate into either normal (light) or preferably heavy water.  The reactor was called an aqueous homogenous reactor.  Imagine my surprise when I found out that two of these reactors were actually built!  They also had some incredible safety characteristics.  Because the water would expand when heated, which reduced neutron moderation, the reactor had a huge negative temperature coefficient.  Like a mass on a stiff spring, it was essentially impossible to get the reactor to have an "excursion" into a damaging region of operation.  Additionally, the decay heat (the heat generated by the decay of fission products, which remains even when the fission reaction has stopped) can be passively removed by draining the fuel into a different cooling configuration.  This is simply not possible with a solid-fueled reactor, which is why a failure in the pressure vessel is so seriously.  In addition, because the fuel was in a fluid, adding additional fuel as the reactor operated was easy, as was removing fission products during reactor operation.  Each of these steps is terribly difficult in a solid-fueled reactor--to "reprocess" solid fuel, you essentially have to chop it up, dissolve it in acid, and then separate everything chemically.  Basically you can only reprocess liquid fuel--if you have solid fuel you have to make it liquid--this reactor already had liquid fuel.

But despite all these advantages, the aqueous homogeneous reactor had a serious drawback.  By using water at the solvent/moderator, you were limited to rather low temperatures and high pressures by the characteristics of the water itself.  The next reactor in the book had all the advantages without this disadvantage--the molten fluoride reactor.

Most nuclear engineers are familiar with the role fluorides play in the "standard" nuclear cycle.  Mined uranium, which is in the form of uranium oxide, is converted to uranium tetrafluoride (UF4) by exposing it to fluorine gas.  The tetrafluoride, called "green salt" is then further exposed to more fluorine to form uranium hexafluoride (UF6), often called "hex" or "red salt".  UF6 is a gas at slightly higher than room temperature, and is used in gaseous diffusion or centrifuge plants to enrich uranium.  After enrichment, the enriched hex is converted back to uranium oxide and made into solid fuel for typical reactors.

UF4 has a very high melting temperature (1035 C), but when it is combined with other fluoride salts, the melting temperature is reduced dramatically.  The optimum solvent salts appear to be lithium fluoride and beryllium fluoride.  A combination of these salts with UF4 results in a salt that melts at 450 C.  But most importantly, the resultant fuel mixture can operate over a large temperature range at essentially ambient pressure.  That means that the large pressure vessel typical of most water reactors isn't needed.  That's a huge safety improvement and a big weight reduction item for a space reactor.  The molten-fluoride reactor retains all the safety features of the aqueous homogenous reactor (large negative temperature coefficient, passive decay heat removal, online fuel addition and fission-product removal) and adds more attractive features important for a space reactor:  low pressure operation, passive launch safety, and high temperature capability.

I'm frustrated that this reactor wasn't considered for Prometheus because I really think this reactor would have solved many of the basic problems they were running into, like fuel qualification, system complexity, and high-temperature heat rejection.  I still can't find a good technical reason why it wasn't being investigated--but now NASA is talking about pursuing NTR and I feel like we're slipping even further away from anything practical.  The issues of testing and qualifying NTR fuel make the fuel issues on Prometheus look like a walk in the park.

Offline Chris Bergin

RE: Role of NTR/BNTR/NEP in future architectures
« Reply #36 on: 01/02/2006 05:12 PM »
Quote
vanilla - 2/1/2006  5:19 PM

Indeed, there were actually three totally different approaches to reactor design outlined in this book, all of them with the goal of building a thorium-fueled thermal breeder reactor.

One technique was to dissolve uranium sulfate into either normal (light) or preferably heavy water.  The reactor was called an aqueous homogenous reactor.  Imagine my surprise when I found out that two of these reactors were actually built!  They also had some incredible safety characteristics.  Because the water would expand when heated, which reduced neutron moderation, the reactor had a huge negative temperature coefficient.  Like a mass on a stiff spring, it was essentially impossible to get the reactor to have an "excursion" into a damaging region of operation.  Additionally, the decay heat (the heat generated by the decay of fission products, which remains even when the fission reaction has stopped) can be passively removed by draining the fuel into a different cooling configuration.  This is simply not possible with a solid-fueled reactor, which is why a failure in the pressure vessel is so seriously.  In addition, because the fuel was in a fluid, adding additional fuel as the reactor operated was easy, as was removing fission products during reactor operation.  Each of these steps is terribly difficult in a solid-fueled reactor--to "reprocess" solid fuel, you essentially have to chop it up, dissolve it in acid, and then separate everything chemically.  Basically you can only reprocess liquid fuel--if you have solid fuel you have to make it liquid--this reactor already had liquid fuel.

But despite all these advantages, the aqueous homogeneous reactor had a serious drawback.  By using water at the solvent/moderator, you were limited to rather low temperatures and high pressures by the characteristics of the water itself.  The next reactor in the book had all the advantages without this disadvantage--the molten fluoride reactor.


This is a superb thread - and also a heavy learning curve.

Thorium-fueled thermal breeder reactor, and more so the molten fluoride reactor - do we have any available web-based resources on these concepts for further learning? Also allow me to forward this thread to a couple of MSFC guys who are pretty savvy on such propulsion/energy concepts.

Thanks to Vanilla (and all) for some facinating insights.

Offline kfsorensen

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #37 on: 01/02/2006 05:36 PM »
Quote
Chris Bergin - 2/1/2006  12:12 PM
Thorium-fueled thermal breeder reactor, and more so the molten fluoride reactor - do we have any available web-based resources on these concepts for further learning? Also allow me to forward this thread to a couple of MSFC guys who are pretty savvy on such propulsion/energy concepts.

If you make some space available on your FTP area, I will upload a number of documents related to the topic.

Offline Chris Bergin

RE: Role of NTR/BNTR/NEP in future architectures
« Reply #38 on: 01/02/2006 05:46 PM »
Thanks. I've responded on potential routes on facilitating that by PM.

Offline Orbiter Obvious

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RE: Role of NTR/BNTR/NEP in future architectures
« Reply #39 on: 01/02/2006 06:24 PM »
Are those new forms available to be used in space transportation? Or are they like the Nuclear fission possibilities, which are meant to be about 20-30 years away?

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