Two-Fluid Effects on Reactor Thermal-Hydraulics

Abstract

The two-fluid effects on the reactor thermal-hydraulics are presented. Emphasis is placed on the fundamental physics of the two-fluid model. The relationship and compatibility between one-fluid and two-fluid models in their physical behaviour are discussed. The noticeable two-fluid effects (phase slip, liquid superheat and condensation) are illustrated in the simulations of experimental tests (level swelling, pipe blowdown and water hammer). In spite of some uncertainties still remaining in the two-fluid constitutive relations, the two-fluid model is probably the most accurate model for simulating the two-phase flows in reactors.