Doubling Time

Sometimes it is useful to discuss the rate of change of reactor power in terms similar to those used in radioactive decay calculations. Doubling or halving time are terms that relate to the amount of time it takes reactor power to double or be reduced to one-half the initial power level. If the stable reactor period is known, doubling time can be determined as follows.

Doubling time (DT) = τ(ln 2)
where:
τ= stable reactor period
ln 2 = natural logarithm of 2

When the doubling time is known, the power level change from P_o is given by the following equation.

where:

t = time interval of transient
DT = doubling time