6. TYPICAL RUNNING TIME
ONETRAN is approximately twice as slow as DTF-IV per inner iteration for the same space-angle mesh. However, ONETRAN has twice as many unknowns per spatial mesh cell and a coarser spatial mesh than DTF-IV will normally give equivalent accuracy. Furthermore, ONETRAN will usually converge to DTF-IV equivalent accuracy in fewer total iterations.
A 6-group, 106-interval mesh, S2 K-eff calculation with four outer iterations of an EBR-II core reqires 7.5 s on the CDC 7600. A 20- group, 134-interval mesh, S4 K-eff cell calculation with 12 outer iterations requires 5.5 min on the CDC 7600.
The 13 test cases included in the package have been executed by NEA- DB on IBM 3033 in 741 CPU seconds.