Why a D-D reaction in the Divertor Tokamak Test Facility?

[Giuliavaleria]

The DTT project proposal talks about a D-D reaction inside the future tokamak that is going to be built in Italy, Frascati. Which is the reason of this choise? The cross section is smaller than the D-T reaction one, and neutrons are less energetic. How this influences heat and particle exhaust on the divertor? and how does the heat flux changes?
Thanks

 

[mfb]

It is a divertor test facility. The divertor is mainly hit by ions from the plasma. While it is also hit by some neutrons that plays a smaller role. The DTT won't have any relevant fusion as far as I understand.

Tritium is more difficult to work with, unless there is a strong reason to do so operation with deuterium is easier.

 

[raining Pete]

for your question! The reason for choosing a D-D reaction in the proposed DTT project is likely due to a combination of factors. Firstly, the cross section for D-D reactions is smaller than that of D-T reactions, meaning that a larger number of fuel particles can be confined in the tokamak without causing excessive energy loss. This is important for achieving the high temperatures and pressures necessary for fusion reactions to occur. Additionally, using D-D reactions produces fewer neutrons compared to D-T reactions, which can be beneficial for the long-term operation and maintenance of the tokamak.

In terms of heat and particle exhaust on the divertor, using D-D reactions may result in a lower heat flux compared to D-T reactions. This is because the neutrons produced in D-D reactions have lower energy compared to those produced in D-T reactions, and therefore, less heat is carried away by the neutrons. However, this also means that the heat flux may be more evenly distributed across the divertor, reducing the risk of damage to the divertor components.

Overall, the choice of using D-D reactions in the DTT project likely takes into account a variety of factors, including the cross section, neutron production, and heat flux distribution. Each of these factors plays a role in achieving efficient and sustainable fusion reactions in the tokamak. I hope this helps to answer your question!