ENGINEERING DESIGN AND ANALYSES OF THE ALT-II PARTICLE COLLECTION SCOOPS AND DEFLECTOR PLATES

The magnetic field line tracing and heat transfer analyses required for the design of the particle collection scoops and deflector plates for the Advanced Limiter Test-II (ALT-II) are described, and special fabrication techniques are discussed. For the magnetic field line analysis, expressions for the poloidal and toroidal magnetic fields based on Shafranov stability criteria were used to define areas located at the back of the blade which are shadowed by adjacent deflector plates. The outline of the shadowed areas was then used to contour the sides of the particle collection scoops. Finite element thermal analyses were used to determine the response of the deflector plates, and to adjust the design for the anticipated incident peak heat fluxes of 3000 W/cm2. Based on the thermal analyses, a 2 mm overhang of the armor tiles over the edge of the blade was selected, and pyrolytic graphite was chosen as the deflector plate material. The computer aided design and fabrication methods used to complete assemblies, including a transfer of computer-aided-design data to numerical control machining tapes, are discussed, and some of the experience gained is summarized.