Stirling Nuclear Reactors?

[Carcano]

It strikes me that the primary safety vulnerability of current nuclear reactors is the pipes that can rupture, and the pumps that can fail.



Isnt it time to come up with a simpler design that doesnt need all these systems external to the core itself.

Why can we have a larger scale version of a Radioisotope Generator that uses a Beta Stirling engine to convert heat to rotary motion. This would also eliminate the turbine stage.

http://en.wikipedia.org/wiki/Advance...tope_Generator



Instead of using Plutonium-238 why not use conventional fuel rods housed inside an iridium-titanium core that is surrounded not by water but by HELIUM contained in an insulated piston cylinder?

[billvon]

Instead of using Plutonium-238 why not use conventional fuel rods housed inside an iridium-titanium core that is surrounded not by water but by the AIR contained in an insulated piston cylinder?

Because they don't give off much energy. Low enrichment fuel rods (the sort used by nuclear power plants) give off very little decay heat when new.

[Carcano]

Because they don't give off much energy. Low enrichment fuel rods (the sort used by nuclear power plants) give off very little decay heat when new.

The most efficient Stirling engines use HELIUM as the working gas, and operate at very high temperatures.

So, why not use graphite moderated cores that already use helium as the coolant...as we see in this British design.

[Aqueous Id]

In any case you have to be able to draw huge amounts of heat from the reactor, and, as we saw in Japan, that heat transfer has to continue long after the reaction is shut down, or the core will melt. With or without Stirling engines in the power plant, there has to be fluid to transport the heat. I can't see how changing the fluid changes the safety concerns over piping and pumps. If you are asking how to avoid meltdown, the obvious answer is that cooling has to be available 24/7. . . even during earthquakes and tsunamis.

[Carcano]

In any case you have to be able to draw huge amounts of heat from the reactor, and, as we saw in Japan, that heat transfer has to continue long after the reaction is shut down, or the core will melt. With or without Stirling engines in the power plant, there has to be fluid to transport the heat. I can't see how changing the fluid changes the safety concerns over piping and pumps. If you are asking how to avoid meltdown, the obvious answer is that cooling has to be available 24/7. . . even during earthquakes and tsunamis.

I started thinking about this because the 80 MW nuclear submarines are impervious to earthquakes and tsunamis...for obvious reasons.

I also suddenly realized why Japan would build a plant right on the coast in a tsunami zone. Its probably because any fallout from an accident would be swept towards the ocean by the wind...instead of settling over Japanese territory. Contamination of water would be ocean water...not fresh water used by the population.

The advantage of transferring heat with a stirling engine is that there is no steam turbine...no pipes or pumps that can be damaged, as we see in the design for the space probe power system pictured above.

[Carcano]

Apparently nuclear submarines are cooled simply by using the hull as a radiator slicing through the ocean...leaving a wake of warm water.

What a terrible waste to see those giant cooling towers at electric power plants.

A waste not only of heat but of pure distilled water as well.

I'm surprised no one has thought of a plan to channel all that volume into the city water supply. Residents can extract some of the waste heat with in-home exchangers.

[billvon]

The most efficient Stirling engines use HELIUM as the working gas, and operate at very high temperatures.

So, why not use graphite moderated cores that already use helium as the coolant...as we see in this British design.

You could. However:

1) The diagram shows a critical reactor, not an RTG (i.e. decay heat.)

2) Helium has a low volumetric heat capacity. Thus the reactor would have to be big physically (or have higher flow rates) compared to a PWR. This isn't the end of the world; HTGR's use helium with good results.

[Carcano]

Helium has a low volumetric heat capacity. Thus the reactor would have to be big physically (or have higher flow rates) compared to a PWR. This isn't the end of the world; HTGR's use helium with good results.

When the end of the world comes...its too late to plan for it.

A solar storm similar to the Carrington Event of 1859 could have very dire consequences for the electrical grid.

http://en.wikipedia.org/wiki/Solar_storm_of_1859

Theres also the issue of initial costs. If a reactor design could eliminate the steam turbine phase, and have every component aligned horizontally, this would greatly diminish the capital investment required.

This is the massive turbine, gear set and generator assembly housed in a separate building at Diablo Canyon.

[roselina366]

As i remember i had read about on nuclear reactor in 7th standard.But at that time i can't understand its uses and its process.But after reading your post now i understand the whole thing properly so thanks to give me huge information about this.

[billvon]

Theres also the issue of initial costs. If a reactor design could eliminate the steam turbine phase, and have every component aligned horizontally, this would greatly diminish the capital investment required.

A Stirling engine is going to have much higher initial costs than a turbine. A good turbine/generator set has one big moving part and all it does is spin. A Stirling engine has a reciprocating piston that drives a crankshaft; that takes a lot more engineering, wears a lot faster, is a lot more expensive to build etc.