Respuesta :
Answer:
negative reactivity is equal to 1.68 × 10⁻³Bq
Explanation:
given,
constant power level = 2.7 MW
power drop of 1 watt in 15 minutes.
power rises in the form of non linear form of reactivity
[tex]\dfrac{P}{P_0}=\dfrac{\beta (1 - \beta )}{\beta -\rho}\ e^{(\dfrac{\lambda \rho}{\beta - \rho})\ t}[/tex]
assuming Pj = 1
[tex]ln(\dfrac{P}{P_0P_j})= -\dfrac{t}{T_P}[/tex]
[tex]ln(\dfrac{1}{2.7 \time 10^6})= -\dfrac{900}{T_P}[/tex]
Tp = 60.77 s
the approximate Tp is calulated now to calculate reactivity
[tex]T_p = (\dfrac{\beta - \rho}{\lambda \rho})[/tex]
[tex]\rho = \dfrac{\beta}{1+\lambda\ T_p}[/tex]
[tex]\rho = \dfrac{0.0065}{1-0.08\times 60.77}[/tex]
ρ = - 1.68 × 10⁻³Bq
hence, negative reactivity is equal to 1.68 × 10⁻³Bq
