1. Code Integration for Efficient Divertor Design H. McGuinness D. Steiner ARIES project meeting UCSD, Nov 4-5 2004 Nuclear Engineering Rensselaer Polytechnic Institute

2. Code System VMEC Plasma Equil. Field lines GOURDON MFBE Mag. Field GOURDON Guid. Centers In/out LCMS ? GEOM Geometry Orbit3D Alpha loss. Data Footprints / Heat Loads GEOM Geometry Input Coil Currents GRID Vac. Field GOURDON Field lines DESCUR Fouri. app. LCMS VMEC Plasma Equil. MFBE Mag. Field GOURDON Field lines Mass Profile Input Field lines GOURDON Input Particle dist. Data Footprints / Heat Loads? Orbit3D Alpha loss.

3. Future Capabilities ORBIT3D GEOM GOURDON Parallized version  Many more lines Capable of tracing guiding centers  ?? T3E version  X1 at ORNL, Convert? Inclusion of gyro radius  more accurate description of α loss Utilize GEOM also? Utilize GEOM  Faster run times, simple intersection data Input PFC, FW, LCMS geometry  Tagged map of geometry

4. The GEOM Code GEOM = GEOmetric Mapping IN OUT Geometry of PFCs, FW, LCMS “Tagged” 3D array of geometry Each “area” has unique numerical tag Like MFBE, divides ROI into grid (N Ф, N R, N Z ) Areas = divertor region, between LCMS and FW, surfaces Each cell recieves numerical tage via process of complex integration on point (like MFBE) Compute IM of contour around surfaces Parallelized in the Toroidal direction

5. GEOM Conintued

6. Can be used to find intersection data for arbitrarily shaped surface. GEOM/GOURDON Interface GOURDON reads in GEOM tagged mapping Every integration step, it queries the tag cell If appropriate tag, GOURDON does expensive location calculation Saves time, easy to track intersection with PFC/FW (even LCMS) GEOM introduces no error

7. GOURDON Output Current GOURDON traces fieldlines Use Lc to find approx. for heat flux Heat Loads, Peaking factors, etc

8. Long Lc? Guiding centers… What if Lc is too long for analytic model? Trace guiding centers instead… Directly find energy deposited by particles

9. Conclusion New codes will be introduced to help in divertor design GEOM: Simple geometry input, speeds up GOURDON GOURDON: Parallelized, guiding centers ORBIT3D: gyro-radius, GEOM? Need more advanced codes for final design?