Benchmarking verification of the control rod effects on the MTR core parameters using the MTR-PC and MCNP codes throughout 3D core modeling and rod-drop experiment

• Introducing and developing a high reliable core calculations and modeling.
• Introducing the standard safety issues and concepts.
• Triple benchmarking process via deterministic, stochastic and experiments.

Verification of nuclear data and codes is highly recommended for reactor safety analyses. In this research, MTR-PC package and MCNP 4C are used as deterministic and Monte Carlo simulation code, respectively. They are taken into account safety parameters as a function of control rods. Control absorbers classified in two different types. The first called Shim Safety Rods (SSR) made of an Ag–In–Cd composition, and the second one is the Fine Regulating Rod (FRR) made of Stainless Steel. One startup test of a 5 MW Material Testing Reactor (MTR) is simulated throughout the 3-D core modeling. It checks the overall simulating performance. Reactivity worth effects of control rods are calculated and benchmarked against rod-drop experimental results. Both types of codes are taken into account the integral and differential behavior of reactivity worth effects. The startup state has been simulated very carefully, and also total reactivity worth effect of control rods differs from the measured value less than 1.1% (in pcm). Results are in good agreement and highly reliable to calculate the total reactivity worth effect of control rods, and to simulate the startup state of MTRs as Best Estimate (BE) tools.