Uncertainty evaluation of calculated and measured kinetics parameters of Tehran Research Reactor

✍ Scribed by Seyed Abolfazl Hosseini; Naser Vosoughi

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 490 KB
• Volume: 240
• Category: Article
• ISSN: 0029-5493
• DOI: 10.1016/j.nucengdes.2010.05.007

✦ Synopsis

Effective delayed neutron fraction ˇeff and neutron generation time are important factors in reactor physics calculation and transient analysis. In the first stage of this research, these kinetics parameters have been calculated for two states of Tehran Research Reactor (TRR), i.e. cold (fuel, clad and coolant temperature 20 • C) and hot (fuel, clad and coolant temperature 65, 49 and 44 • C, respectively) states using MTR PC computer code. The ratio of (ˇe ff ) i /(ˇe ff ) core plays an important role in reactivity accident analysis codes. This parameter and its contribution to effective delayed neutron fraction from each nucleus have been calculated in cold and hot reactor states. Uncertainty of effective delayed neutron fraction is evaluated in terms of following four quantities; basic delayed neutron constants, delayed neutron spectra, energy dependence of delayed neutron yield ( d ) and fission cross-section of 235 U and 238 U. In the second stage, these parameters have been measured with an experimental method based on Inhour equation. The calculated and measured values are in good agreement. Relative Percent Errors (RPEs) are 2.8% for ˇeff and 5.7% for in the cold state.