vacuum_variables Module

switch for vacuum pumping model:

• ='old' for old detailed ETR model
• ='simple' for simple steady-state model with comparison to ITER cryopumps

number of high vacuum pumps (real number), each with the throughput of one ITER cryopump (50 Pa m3 s-1), all operating at the same time (vacuum_model='simple')

switch for vacuum pump type:

• =0 - for turbomolecular pump (magnetic bearing) with speed of 2.0 m3/s (1.95 for N2, 1.8 for He, 1.8 for DT)
• =1 - for compound cryopump with nominal speed of 10.0 m3/s (9.0 for N2, 5.0 for He and 25.0 for DT)

number of ducts (torus to pumps)

vacuum system duct length scaling

base pressure during dwell before gas pre-fill(Pa)

divertor chamber pressure during burn (Pa)

Pump throughput (molecules/s) (default is ITER value)

plasma chamber wall outgassing rate (Pa-m/s)

neutral gas temperature in chamber (K)

mass of vacuum duct shield (kg)

diameter of duct passage (m)

number of high vacuum pumps

switch for dwell pumping options:

• =0 pumping only during tdwell
• =1 pumping only during tramp
• =2 pumping during tdwell + tramp

area of one pumping port as a fraction of plasma surface area

maximum pumping speed per unit area for deuterium & tritium, molecular flow

effective pumping speed reduction factor due to duct impedance

initial neutral pressure at the beginning of the dwell phase (Pa)

outgassing decay index

outgassing prefactor kw: outgassing rate at 1 s per unit area (Pa m s-1)