Reactor physics calculations and their experimental validation for conversion and upgrading of a typical swimming pool type research reactor

Detailed neutronic analysis of a typical swimming pool type research reactor, Pakistan Research Reactor-1 (PARR-1), was carried out for conversion of its core from 93% highly enriched uranium to 20% low enriched uranium fuel with power upgrading from 5 to 10 MW. Standard computer codes WIMS-D/4 and CITATION were employed to calculate core excess reactivity, power defect, reactivity e€ect of xenon and samarium, reactivity worth of fuel ele- ment, worth of control rods, shutdown margin, reactivity feedback coecients, neutron ¯ux and power peaking factors. A series of low and high power tests were performed on the newly converted core to determine its performance. A comparison between the calculated and mea- sured results is presented in this article. The agreement is generally good.