Question

7. A heterogeneous uranium-water lattice consists of a square array of natural uranium rods 1.50 cm in
diameter with a pitch of 2.80 cm. Calculate the: (a) radius of the equivalent cell; (b) uranium-water volume ratio
VF/VM; (c) thermal utilization; (d) resonance escape probability; (e) fast fission factor (from Fig. 6.10); (f) k

Answer 1

Given that

a=d/2= 0.75 cm

a) radius of equivalent cell is given as

b) the uranium-water volume ratio is calculated as

c)

thermal utilization is

hence,

At 20 C,

we have

thus,

d)

e)  

f)