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The code has been used successfully to reproduce the sizing and costing of TFTR in order to calibrate the various models.This report must be preceded or accompanied by a Cost relationships have been developed for both plant and capital equipment and for annual utility and fuel expenses. The size modeling allows considerable freedom in specifying physics assumptions, operating scenarios, TF operating margin, and component geometric and performance parameters. Plasma heating is assumed to be by neutral beams, and impurity control is either passive or by a poloidal divertor system. The PF coil self and mutual inductances are calculated from the geometry, and the PF coil power supplies are modeled to account for time-dependent profiles for voltages and currents as governed by input data. The ohmic heating (OH) coils are located within the machine bore and have an air core, while the shaping field (SF) coils are located either within or outside the TF coils. For the poloidal field (PF) coil systems copper conductors are assumed.
The coil technologies are: (1) copper (both room temperature and liquid-nitrogen cooled), (2) superconducting NbTi, (3) superconducting Nb/sub 3/Sn, and (4) a Cu/NbTi/ hybrid. Currently, the code provides a tool for the systematic comparison of four toroidal field (TF) coil technologies allowing both D-shaped and circular coils. Considerable detailed design and analyses have provided the basis for the thermal, electrical, mechanical, nuclear, chemical, vacuum, and facility engineering of more » the various subsystems. A generalized description of TNS is incorporated in the code and includes refined modeling of over forty systems and subsystems. The ORNL/Westinghouse study of TNS (The Next Step) has involved the investigation of a number of device options, each over a wide range of plasma sizes. The code was written to conduct detailed analyses on the engineering features of the next tokamak fusion device following TFTR. « lessĪ FORTRAN code for the COsting And Sizing of Tokamaks (COAST) is described. A number of changes have been made in the design since the conceptual design review, and are described in this paper. The superconducting magnet system has gone through a conceptual design review, and is in preliminary design started by the LLNL/MIT/PPPL collaboration.
All of the coils are cooled by flowing supercritical helium, with inlet and outlet connections made on each double pancake. = Sn) or niobium titanium (NbTi) superconducting strands depending on the operating conditions for that coil.