ASI (Axial Shape Index)

Question 1

Which one of the following will dampen divergent axial power oscillations?

A. Boration as ASI crosses ESI headed in the negative direction.
B. Rod insertions as ASI crosses ESI headed in the negative direction.
C. Rod insertion as ASI crosses ESI headed in the positive direction.
D. Rod withdrawal as ASI crosses ESI headed in the negative direction.

Answer 1

B. Rod insertion as ASI crosses ESI headed in the negative direction.

(Note: Positive is below the ESI and Negative is above ESI.)

Question 2

Which one of the following statements explains why divergent axial power oscillations must be controlled?

A. Higher and higher xenon concentration after each oscillation will eventually shut the reactor down.
B. The control element drive mechanism system is not designed to control large xenon oscillations.
C. High local power density peaking will eventually trip the reactor on either DNBR-low or Linear Power Density-high.

Answer 2

C. High local power density peaking will eventually trip the reactor on either DNBR-low or Linear Power Density-high.