Attya A. Abou-Zaid
Reactors Department, Nuclear Research Center, Atomic Energy Authority, P. O. Box 13759 Cairo, Egypt
The measurements of geometrical distribution of thermal neutron flux in research reactors are often used
in the field of reactor operation and reactor physics. Usually such measurements are carried out by using
the gold wire activation method. This method has been used for measuring a thermal neutron flux at
the location of a Cobalt Irradiation Device (CID) of ETRR-2. A special device was used for locating
samples in an irradiation box and the measurements were performed for seventy-two positions. The Monte
Carlo MCNP-4B code has been used for the modeling and simulation of ETRR-2 core with structural materials
and surrounding beryllium reflectors. The device used in the flux measurement was also simulated in
the MCNP-4B model. The thermal flux has been calculated and compared with the experimental one. The results
show good agreement between the measured and calculated flux.