Include the cryostat in the vertical build table
Closed this issue · 1 comments
The Vertical Build table does not include the outer thermal shield or the cryostat. The supporting structure for the cryostat roof is rather large so it would be good to include this.
The vertical build is shown here:
Proposed solution
Add the vertical coordinates of the outer thermal shield and the cryostat to the vertical build table in OUT.DAT. Relevant variables:
real(dp) :: tftsgap
!! Minimum metal-to-metal gap between TF coil and thermal shield (m)
real(dp) :: thshield_ib
!! TF-VV thermal shield thickness, inboard (m)
real(dp) :: thshield_ob
!! TF-VV thermal shield thickness, outboard (m)
real(dp) :: thshield_vb
!! TF-VV thermal shield thickness, vertical build (m)
real(dp) :: vgap2
!! vertical gap between vacuum vessel and thermal shields (m)PROCESS/source/fortran/blanket_library.f90
Lines 496 to 497 in 2cb3ee9
Comments
Ideally it would be good to include the uppermost PF coil in the table, but theoretically this could overlap with the vertical coordinates of the TF coil, so that would be complicated. The parameter clh1, not shown in the diagram, gives the vertical clearance from TF coil to cryostat (m).
Note that there are several issues pointing out that the vertical build calculation is not consistent for the single null case. I won't attempt to fix this.
For the moment I will use the same space allowance on the bottom of the machine. This is probably not required for the cryostat base itself, which can be made rigid by bolting it to the floor, but the gravity support has been omitted so these two errors may cancel out.
From the engineering point of view it might be better to put the supporting truss on the outside of the cryostat rather than the inside. This makes no difference to the overall size of the structure.
The output now looks like this:
*********************************************** Vertical Build ***********************************************
Cryostat roof structure* 5.604 14.105 (clh1)
TF coil 0.916 8.500 (tfcth)
Gap 0.050 7.584 (tftsgap)
Thermal shield, vertical 0.050 7.534 (thshield_vb)
Gap 0.163 7.484 (vgap2)
Vacuum vessel (and shielding) 0.900 7.321 (d_vv_top+shldtth)
Gap 0.020 6.421 (vvblgap)
Top blanket 0.850 6.401 (blnktth)
Top first wall 0.018 5.551 (fwtth)
Top scrape-off 0.600 5.533 (vgaptop)
Plasma top 4.933 4.933 (rminor*kappa)
Midplane 0.000 0.000
Plasma bottom 4.933 -4.933 (rminor*kappa)
Lower scrape-off 2.002 -6.935 (vgap)
Divertor structure 0.620 -7.555 (divfix)
Vacuum vessel (and shielding) 1.000 -8.555 (d_vv_bot+shldlth)
Gap 0.163 -8.718 (vgap2)
Thermal shield, vertical 0.050 -8.768 (thshield_vb)
Gap 0.050 -8.818 (tftsgap)
TF coil 0.916 -9.734 (tfcth)
Cryostat floor structure** 5.604 -15.339 (clh1)
*Cryostat roof allowance includes uppermost PF coil and outer thermal shield.
**Cryostat floor allowance includes lowermost PF coil, outer thermal shield and gravity support.