New design aspects of cooling scheme for SST-1 plasma facing components

•SST-1 Tokamak PFCs were fabricated using graphite tiles embedded on CuCrZr and CuZr back plates.•PFC cooling is designed considering maximum heat load up to 0.6MW/m2.•Cooling scheme is such that the nucleate boiling will not occur.•The required mass flow rate and velocity for cooling water in each sub-connection are found to be 0.43kg/s and 5.5m/s for efficient heat extraction.•The header distribution scheme is modeled using AFT fathom which is in agreement to the required parameters with maximum 5% of deviation. PFC of SST-1 comprising of baffles, divertors and passive stabilizers have been designed and fabricated for a maximum heat load up to 1.0MW/m2. In operational condition, SST-1 divertors and passive stabilizers are expected to operate with a heat load of 0.6 and 0.25MW/m2, respectively. During plasma operation, the heat loads on PFC are required to be removed promptly and efficiently. Thereby the design of an efficient cooling scheme becomes extremely important for an efficient operation of PFC. PFCs are also baked up to 350°C in order to remove absorbed moistures and other gases. 3D thermal analysis of PFC using ANSYS has been carried out to ensure its thermal stability. The cooling parameters have been calculated according to average incident flux on divertors and passive stabilizers. Engineering design demonstrated the required mass flow rate and velocity for cooling water in each sub-connection are optimized to be 0.43kg/s and 5.5m/s for efficient heat extraction under steady state heat load. Maximum temperature which PFC could be maintained is 355°C and is well within threshold limits of material property degradation. The header distribution, modeled using AFT fathom, resulted for required parameters within maximum 5% of deviation.