New Reactor Concepts
9.2
reflector tank. As presence of water in this region reduces the
MULTIPURPOSE RESEARCH REACTOR
thermal neutron flux levels in the reflector region, maximum
Considering the present and future requirements of research
water gap between filler and reflector tank will be restricted.
reactor based facilities design of a new “Multi Purpose Research
Reactor” (MPRR) has been undertaken. The MPRR with its high
The reactor block consists of two isolatable water filled bays,
neutron flux and irradiation volume will provide the platform for
reactor bay and fuel storage bay. The bays are lined with SS 304L
research in reactor fuels, reactor materials, condensed matter
plates. For the beam tube research a separate area is provided in
research for study of structure and dynamics of materials, stress
the reactor building. The researchers’ area and the reactor pool
analysis of engineering components especially the reactor
are sized such that adequate core submergence is always assured
materials, neutron radiography, time of flight refractrometry,
even in the event of a rupture of beam tube.
small sample investigations for the study of new and novel
materials. The MPRR will supplement the isotope production
capacity of Dhruva and Cirus research reactors to meet the
projected requirements of various isotopes beyond the year 2015.
Neutron Flux Distribution
The proposed reactor is a 20 MW (thermal) research reactor
with a maximum thermal neutron flux of 5.0 x 1014 n/cm2/sec.
It will be fuelled with Low Enriched Uranium (LEU) (19.75 wt %
U235) dispersion type fuel (U3Si2-Al) and will use de-mineralised
water as coolant and moderator. The reactor core will be
surrounded by an annular heavy water reflector tank to obtain a
large irradiation volume to maximize the number of irradiation
positions available for isotope production and material irradiation.
Core Layout
Most of the irradiation positions will be accommodated in the
heavy water reflector tank surrounding the core. The heat from
primary coolant system is ultimately dissipated to atmosphere
through a cooling tower system, which acts as a secondary coolant
system. The reactor block will be housed in a confinement building.
The reactor core is constituted by 37 lattice positions laid in 5 x
5 square array at a square pitch with three positions added on
each side. The nominal core consists of 28 standard fuel assemblies
and 6 control fuel assemblies. The central and two peripheral
positions will be used for high irradiations requiring high neutron
flux. Graphite/beryllium fillers occupy the space between the
peripheral core lattice assemblies and the inner surface of the
Reactor Technology & Engineering
Reactor Block
BARC HIGHLIGHTS
155
New Reactor Concepts
Experimental positions
Experimental facilities are provided both in the reactor core and
reflector tank. Three lattice positions are provided for in-core
irradiation of samples requiring high neutron flux. The positions
can be used for material irradiation or isotope production. Seven
tangential beam tubes are provided for beam tube research,
neutron radiography and detector testing & calibration. A total
of 15 vertical tubes of assorted sizes are provided in the reflector
tank. These positions can be used for the production of isotopes,
silicon doping, etc. Most of these irradiation positions are located
in the region of highest neutron flux.
K. Sasidharan and S.B. Chafale, <[email protected]>
156
BARC HIGHLIGHTS
Reactor Technology & Engineering
3-D flux distribution