Title: Prediction of helium vapor quality in steady state Two-phase operation for SST-1 Toroidal field magnets,
Abstract: Steady State Superconducting Tokamak (SST-1) at the Institute for Plasma
Research (IPR) is an operational device and is the first superconducting
Tokamak in India. Superconducting Magnets System (SCMS) in SST-1 comprises of
sixteen Toroidal field (TF) magnets and nine Poloidal Field (PF) magnets
manufactured using NbTi/Cu based cable-in-conduit-conductor (CICC) concept.
SST-1, superconducting TF magnets are operated in a Cryo-stable manner being
cooled with two-phase (TP) flow helium. The typical operating pressure of the
TP helium is 1.6 bar (a) at corresponding saturation temperature. The SCMS has
a typical cool-down time of about 14 days from 300 K down to 4.5 K using Helium
plant of equivalent cooling capacity of 1350 W at 4.5 K. Using the onset of
experimental data from the HRL, we estimated the vapor quality for the input
heat load on to the TF magnets system. In this paper, we report the
characteristics of two-phase flow for given thermo-hydraulic conditions during
long steady state operation of the SST-1 TF magnets. Finally, the
experimentally obtained results have been compared with the well-known
correlations of two-phase flow.