Abstract
In Japan Atomic Energy Agency (JAEA), a study of the thermodynamic feasibility of straight tube steam generator for Fast Breeder Reactor has been conducted. A coupled simulation system is being constructed which coupled the three dimensional simulation in sodium side with the multi-channel simulation in water side. The CFD code FLUENT was used to simulate the three dimensional flow in sodium side of SG by porous body model. The information exchange model between the sodium side and water side simulation codes was developed for the coupled simulation. A test simulation on the straight-tube steam generator system was carried out, and the accuracy of the coupled simulation model was confirmed.