Gooey Pebble bed reactor

[KerikBalm]

Hmm, you're right, you could bubble it through the inert metal... maybe it could work

[farmerben]

Perhaps there is a way to make the propellant much hotter than the fuel elements.  

The High Flux Isotope Reactor at Oak Ridge creates a higher neutron flux in the target area than in the fuel itself.  It is possible therefore to isolate the propellant and the reactor by vacuum that only neutrons cross.  

 

[sevenperforce]

7 minutes ago, farmerben said:

Perhaps there is a way to make the propellant much hotter than the fuel elements.  

The High Flux Isotope Reactor at Oak Ridge creates a higher neutron flux in the target area than in the fuel itself.  It is possible therefore to isolate the propellant and the reactor by vacuum that only neutrons cross.  

Gotta seed the hydrogen with tungsten dust or something else that absorbs neutrons, but yeah.

Using radiation for heating and separating the reactor from the propellant is the fundamental concept of the nuclear lightbulb.

[farmerben]

2 hours ago, sevenperforce said:

Gotta seed the hydrogen with tungsten dust or something else that absorbs neutrons, but yeah.

Using radiation for heating and separating the reactor from the propellant is the fundamental concept of the nuclear lightbulb.

Elastic scattering of neutrons off monatomic hydrogen is best.  Absorbtion will in most cases convert neutron kinetic energy into potential nuclear energy.  This can lead to interesting secondary decays.  The interactions of heavy elements like tungsten with neutrons are dominated by inelastic collisions, where the neutron keeps most of it's kinetic energy.  

[sevenperforce]

1 hour ago, farmerben said:

Elastic scattering of neutrons off monatomic hydrogen is best.  Absorbtion will in most cases convert neutron kinetic energy into potential nuclear energy.  This can lead to interesting secondary decays.  The interactions of heavy elements like tungsten with neutrons are dominated by inelastic collisions, where the neutron keeps most of it's kinetic energy.  

That only works if the hydrogen is already monatomic. Diatomic hydrogen is transparent to basically everything.

[Terwin]

On 9/28/2019 at 10:49 AM, sevenperforce said:

I would have to look closely at the fission products of various uranium or plutonium reactor designs in order to get an idea of how lightweight the barrier metal would need to be.

It is a shame that there is no antonym of "dense" other than "lightweight" which is really an antonym of "heavy".

Such as 'Diffuse' or 'Low Density'?

Sparse could also work in some cases.

The problem is that 'Dense' has several similar yet distinct meanings depending on what it is being applied to, so a single antonym would need to cover quite a bit or ground.

Edited September 30, 2019 by Terwin

[sevenperforce]

1 hour ago, Terwin said:

Such as 'Diffuse' or 'Low Density'?

Diffuse is in the ballpark but not quite. Low density works, of course, but there is no monolexical antonym.

[kerbiloid]

2 hours ago, sevenperforce said:

Diffuse is in the ballpark but not quite. Low density works, of course, but there is no monolexical antonym.

"Denseless"?