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Nuclear Engineering
At the Institute of Nuclear Engineering we operate a
two-phase flow experimental laboratory with three
facilities: a scaled hot leg of a PWR reactor with injection
of emergency coolant (COLLIDER), a low pressure loop
with a vertical test section to study bubble condensation
(SCUBA), and a scaled version of a safety coolant tank,
in which steam condensation can be studied. The three
facilities are instrumented with high speed cameras, and
continuous and pulsed lasers with particle velocimetry
techniques. In 2017 a special section in COLLIDER has
been designed and installed that contains a hoop in
the safety injection, similar to advanced PWR designs.
Experiments will be carried out in order to determine the
effect of such a device in the hold-up of coolant in the
leg during LOCA mitigation operations. Such a facility is
unique in the world.
Experiments in the three facilities have provided very
valuable data for the assessment of system codes and
CFD calculations, and have resulted in the development
of new correlations for condensation and counter-current
flow limitation models with entrainment. Collaboration with
the Universidad Politecnica de Madrid has continued and
a new program for the simulation of bubble condensation
in turbulent flows has started with the University Jaume I
in Spain
Counter current flow study in the COLLIDER experimental facility
(by Dr. S. Al Issa)
Experimental Two-Phase Flow Thermal-hydraulics
Projects
■■
SCUBA: Experimental investigation of the condensation
phenomena in large steam bubbles at atmospheric
pressure (E.On Kernkraft)
■■
COLLIDER: Experimental investigation of counter
current flow in a scaled model of the hot leg of a
Konvoi-PWR (E.On Kernkraft)
■■
Experimental studies of condensation in the suppres-
sion pool of BWR reactors (with U. Politécnica de
Madrid (E)
■■
Development of experimental and analytical techniques
for bubble condensation (with Universidad Jaume I,
Castellon (E)
The dual fluid reactor (DFR) is a new concept of nuclear
reactor conceived at the Institute of Solid Matter and
Nuclear Physics (IFK) in Berlin. It consists of a molten salt
core and second molten metal as coolant.
Such a configuration provides the DFR
with many advantages compared to other
current and advanced reactor concepts.
The DFR can destroy the long-lived
radioactive isotopes in spent nuclear fuel,
thus removing the need to supervise nuclear
waste for very long periods of time. The
reactor is also extremely efficient in the
use of the available nuclear fuel resources,
because it can breed new fuel as it operates
and it can use thorium and uranium as fuel.
In 2017 we have continued our research
together with the IFK in order to analyze
the neutronic characteristics of the design
and to determine its safety under a series of
operating strategies. The ultimate goal is to
converge in an optimized and safe design
that can be eventually built. The work has
Development and Design Optimization of the Dual Fluid Reactor (DFR) Concept
made use of coupled analysis computer programs and
models based on the codes ATHLET, TRACE-PARCS and
SERPENT, ANSYS/CFX and COMSOL. These models
have proven their usefulness in design
optimization and safety studies and will be
the basis for further design efforts planned
for 2018 in collaboration with the Center
for Nuclear Research (NCBJ) in Poland and
the TU Dresden.
In collaboration with the IFK, a project
has been carried out aimed at studying
the chemical processing needed for the
on-line elimination of the fission products
from the DFR.
Projects
■■
Development of a coupled neutronic and
thermal-hydraulic models for the dual fluid
reactor concept (molten salt coolant) (E.On
Kernkraft)
■■
NuDest Project: Development of chemical
techniques for the pyroprocessing of fission
products and minor actinides (BMWi)
Radial and axial energy deposition
in the DFR molten salt reactor
(MCNP Calculation).
(Dr. X. Wang, Ph.D. work)