Question

A thermal heterogeneous reactor has a spherical bare core. It uses 3 per cent enriched uranium metals as fuel and Graphite as moderator. The fuel and lattice constants are as follows:

Fast fission factor ? =1.0002

Resonance escape Probability P =0.620

Thermal utilization factor f =0.780

Thermal-fission factor ?=1.845

Transport mean free Path ? ?? =0.66 cm

Calculate the minimum critical dimensions of the core. if any information absent pls just predict some data, since lack of idea to solve it

Answer 1

Answer :

Given :

Fast fission factor ? =1.0002

Resonance escape Probability P =0.620

Thermal utilization factor f =0.780

Thermal-fission factor ?=1.845

Transport mean free Path ? ?? =0.66 cm

For graphite moderator, sizes

M = 53.6 cm

L = 50 cm

Critical size of reactor (radius R) :

where

  

so,

  

putting all the values in above formula, we get :

on calculating, we get

Critical radius of the core R = 2.52083781 m

Thanks