DTU is presently developing the Collective
Thomson Scattering (CTS) diagnostic instrument for the ITER fusion reactor to
measure plasma densities and velocities. While the overall project involves
several departments at DTU, the emphasis in this bachelor project will be on
radiation physics and is carried out at DTU Nutech.
To install the CTS instrument at ITER one needs
to penetrate the blanket. Changes to the blanket may impact radiation levels
throughout the tokamak and its instrumentation. In particular, the mirrors of
the CTS instrument will be subject not only to the microwaves that the mirrors
are constructed to reflect, but also to high energy (MeV range) neutron and
gamma radiation. This radiation results in nuclear heating and it is at this
point an open question whether or not the mirrors need active cooling to
prevent structural damages due to stress inflicted by temperature gradients
across the mirror.
Obviously, the answer to this question may have
consequences impacting other aspects of the CTS design, so it is of utmost
importance that this topic be addressed sooner rather than later.
In the Bachelor project the student will be
given a simplified model to simulate the CTS port plug of the ITER geometry.
Among the first tasks will be to validate this model against the official model
supplied by ITER. By this, the level of accuracy is established and the student
can proceed to make changes to the geometry to implement mirrors according to
present and alternative designs. From the calculated heat-load across the
mirrors it should be determined whether active cooling is required to ensure
the functionality of the mirrors.
1) Based on a geometrical, structural and
plasma description of the ITER tokamak a simplified simulation setup is
provided. Use this as a baseline model, and implement the mirror (geometry and materials)
according to best present design.
2) Compare neutron and gamma flux calculations
to the official ITER MCNP model to validate the simplified model, using the
Source Surface Write capability of MCNP
3) Use Monte Carlo methods to calculate heat
load across the involved mirrors. This will serve as an important input to the
evaluation whether active cooling of the mirrors is needed.
4) If time permits, the first steps toward
calculation of shut-down dose rates in the vicinity of the CTS diagnostic will
Basic to intermediate programming skills