Handbook on Thermal Hydraulic Calculations in Nuclear Power Engineering" , Vol. 2. Ch. 23, Chapter 23 "Thermal Hydraulic Codes, their Potentialities and Uncertainties"

The nuclear reactor safety technology is based on Deterministic Safety Analysis (DSA) and Probabilistic Safety Analysis (PSA). In order to perform DSA, properly qualified computational tools are needed. Among the computation tools, the pivot role is kept by the System Thermal-Hydraulic (SYS TH) code. The SYS TH code has the key attention in the present chapter, even noting that other types of computational tools (noticeably, the Computational Fluid-Dynamic codes, CFD domain) are essential within the framework of DSA. The SYS TH code consists of the following three key modules: • Thermal-hydraulic (or fluid) balance equations solved into the fluid domain. • Fourier equations for conduction heat transfer in solid domain. • Neutron kinetics diffusion equations.