Numerical simulation of draining and drying procedure for the ITER Generic Equatorial Port Plug cooling system

•The cooling system of the ITER Generic Equatorial Port Plug (GEPP) is of a complicated combination of horizontal and vertical channels.•The calculation model for the entire GEPP cooling circuit comprising 12 sub-circuits and built up of 2421 finite-volume elements has been developed.•Transient analysis of this model simulating the draining procedure by the KORSAR/B1 code has been performed.•Water in amount of 263g of initial 531kg in the GEPP remains in the dead-ends of the DSM and DFW channels in 150s of draining procedure.•Almost 3h are required to boil off 263g of water trapped in the dead-ends.