Molten salt Flibe blanket

Page 1 : Molten salt Flibe blanket

Page 2 : Molten salt loop
Page 3 : Heat transfer enhancement of high Prandtl-number fluid
Page 4 : Numerical analysis for electromagnetic fluid
Page 5 : Neutron transport calculation
Page 6 : Published papers

Molten salt Flibe blanket

Molten Flibe (Mix salt of LiF and BeF₂�@LiF : BeF₂ = 66 : 34) is one of the candidates material of fusion blanket. Flibe has not only breeder material Li but also neutron multiplier material Be. In addition Flibe can be coolant as well as liquid Li. The Flibe blanket is being investigated to applying helical type DEMO reactor FFHR designed by National Institute for Fusion Science (NIFS), Japan. We are conduct joint research on the Flibe blanket with NIFS.

Flibe has some advantages and disadvantages for blanket material as follows.

1. Advantages
   
   • Low reactivity with air and water
     
   • Low tritium inventory
     
   • Low electric conductivity (Low MHD effect)
     
2. Disadvantages
   
   • High melting point (732K)
     
   • High Prandtl-number due to its large viscosity
     
   • Corrosive effect with F₂ generated by electrolysis at high velocity
     

In order to solve the above problems, we are investigating heat transfer enhancement technique for high Prandtl-number fluid at low velocity.

Advanced nuclear power and fuel cycle system

We propose "Advanced nuclear power and fuel cycle system" where LWR, FBR, ADS and fusion reactor are jointed to nuclear fuel cycle system. We have to use neutrons of several energy range for nuclear transmutation reactions. Fusion reactors can provide neutrons of 14 MeV, especially we can use the neutron for nuclear transmutation reaction of ⁹⁰Sr. Furthermore, nuclear transmutation reaction of ⁹⁰Sr is neutron multiplication reaction. Therefore, we can use Flibe blanket to the Advanced nuclear power and fuel cycle system; ⁹⁰Sr is mixed to Flibe as a neutron multiplier.

Subjects of research for Flibe blanket

Subjects of this research field are as follows.

1. Study on heat transfer enhancement of high Prandtl-number fluid
2. Development of numerical analysis codes to evaluate heat transfer performance of electromagnetic fluid
3. Neutron transport calculation for nuclear transmutation reaction of ⁹⁰Sr