Nuclear Heat Transfer and Safety Enhancement for VVER-۱۰۰۰ Fuel Assembly

چکیده مقاله

Thermohydrodynamics is numerically analyzed for turbulent flows through a VVER-1000 nuclear reactor rod bundle. The steady state form of the Reynolds-averaged Navier-Stokes (RANS), mass, energy and turbulence equations was discretized and solved using CFX 13.0. For the purpose of numerical analysis, the geometric and boundary conditions were taken from the Bushehr Nuclear Power Plant (BNPP). Since BNPP does not have mixing vane on the grid spacer, two new mixing vanes called the Vane Element Ripped Opener (VERO) and the Vane Inserted Split Operator (VISO) are designed to boost turbulent flow and heat transfer in the subchannels. The computational domain including two grid spacers extend from 100×Dh upstream of the first grid spacer to 250×Dh downstream of the second grid spacer. The results show a considerable increase in the average heat transfer to ~20 Dh downstream of the grid spacer using the mixing vanes on the grid spacer of VVER type reactor. As expected, the pressure loss through the grid spacer also increased slightly with the mixing vanes.