4 ms·
Is putting a big pile of concrete around the reactor not a suitable solution? Concrete is often used as neutron radiation shielding because it's full of hydrog
by darkpuma 7y ago
Is putting a big pile of concrete around the reactor not a suitable solution? Concrete is often used as neutron radiation shielding because it's full of hydrogen (in the water chemically bound up in it) and because of its desirable structural properties.
- snops 7y agoThey already do this with ITER[1] for the "bioshield" to protect humans from radiation, the facility is semi underground as well. However by the sounds of it, a reasonable fraction of the output power is in the form of neutrons. If you had no lithium blanket and just concrete, the energy of the neutrons would go into heating the concrete, where it would either be wasted, or require the concrete to be actively cooled which would be difficult as concrete is not a great conductor. [1] https://f4e.europa.eu/mediacorner/newsview.aspx?content=941 https://f4e.europa.eu/mediacorner/newsview.aspx?content=941
- bbatha 7y agoThe main concern with the neutrons is damage to the reactor itself — you don’t want to have to replace the main chamber walls with any frequency. Fusion reactors generally do not release enough neutrons to hurt people. So shielding on the outside doesn’t do much except provide additional fail safes.
- pfdietz 7y agoThe neutron flux inside a fusion reactor is many orders of magnitude higher than the maximum allowable for human exposure. The flux is low on the outside precisely because of the many absorption lengths of shielding between the reactor and people.