Comparative Analysis of the Dalat Nuclear Research Reactor with HEU Fuel Using SRAC and MCNP5

Giang Phan,Hoang Anh Tuan Kiet,Hoai-Nam Tran,Viet-Phu Tran,Van-Khanh Hoang,Pham Nhu Viet Ha,Kien-Cuong Nguyen

doi:10.1155/2017/2615409

Abstract

Neutronics analysis has been performed for the 500 kW Dalat Nuclear Research Reactor loaded with highly enriched uranium fuel using the SRAC code system. The effective multiplication factors, keff, were analyzed for the core at criticality conditions and in two cases corresponding to the complete withdrawal and the full insertion of control rods. MCNP5 calculations were also conducted and compared to that obtained with the SRAC code. The results show that the difference of the keff values between the codes is within 55 pcm. Compared to the criticality conditions established in the experiments, the maximum differences of the keff values obtained from the SRAC and MCNP5 calculations are 119 pcm and 64 pcm, respectively. The radial and axial power peaking factors are 1.334 and 1.710, respectively, in the case of no control rod insertion. At the criticality condition these values become 1.445 and 1.832 when the control rods are partially inserted. Compared to MCNP5 calculations, the deviation of the relative power densities is less than 4% at the fuel bundles in the middle of the core, while the maximum deviation is about 7% appearing at some peripheral bundles. This agreement indicates the verification of the analysis models.

Highlights

The TRIGA reactor, designed and manufactured by General Atomics (California, USA), is the most common research reactor with 66 facilities in 24 countries [1]
The effective multiplication factors, keff, were analyzed for two cases corresponding to the complete withdrawal and the full insertion of control rods
Thermal neutron flux and power distributions of the Dalat Nuclear Research Reactor (DNRR) core have been analyzed in detail for two cases corresponding to the complete withdrawal and the partial insertion (ShR = 45.7 cm and automatic regulating rod (AR) = 40 cm) of control rods in comparison with

Summary

Introduction

The TRIGA reactor, designed and manufactured by General Atomics (California, USA), is the most common research reactor with 66 facilities in 24 countries [1]. Similar to the TRIGA Mark II reactor, the DNRR consists of many components such as a neutron trap, water gaps, irradiation channels, horizontal beam ports, beryllium blocks, control rods, rotary specimen rack, and graphite reflector. These components make the core geometry complicated. During the startup period of the DNRR core configuration of 88 HEU fuel bundles, several criticality conditions were established with the control rod positions determined experimentally and reported in the startup report of the DNRR [7].

Description of DNRR

Calculation Models

Numerical Calculations and Comparison with MCNP5

Cell 9-6

Findings

Conclusions