Update Irradiation damage.rst

•	Neutron heating values from neutronics simulation (B) are imposed as volumetric heat source across the tungsten monoblock.

•	Temperature dependant heat flux is derived based on the 1D modelling approach which is like that one employed for ITER cooling system.

The thermal properties such as thermal expansion coeeficient, thermal conductivity and specific heat are obtained from literature. In particular, the thermal conductivity (f(dpa, temperature)) of tungsten armour are obtained from the effective thermal conductivity derived from the RVE thermal simulations (F) modelled with irradiation-induced defects. While, the thermal conductivity (f(dpa, temperature)) of copper interlayer and CuCrZr coolant pipe are obtained both from literature and based on some assumptions.

The thermal properties such as thermal expansion coefficient, thermal conductivity and specific heat are obtained from literature. In particular, the thermal conductivity (f(dpa, temperature)) of tungsten armour are obtained from the effective thermal conductivity derived from the RVE thermal simulations (F) modelled with irradiation-induced defects. While, the thermal conductivity (f(dpa, temperature)) of copper interlayer and CuCrZr coolant pipe are obtained both from literature and based on some assumptions.

The thermal boundary conditions imposed across the monoblock is depicted in :numref:`Fig. %s <Monoblock1>`.

    Thermal boundary conditions of Tungsten monoblock.

The FEA thermal simulation is performed by means of Code_Aster script:file:`Scripts/Experiments/Irradiation/Sim/thermal.comm` ::

The attributes of ``Sim`` used for FEA thermal simulation are::

 Sim = Namespace()

 dpa=[0]

 Sim.Name = ['irradiated_day1000']

 # HTC between coolant and pipe (need Coolant and Pipe properties)

 Sim.Pipe = [{'Type':'smooth tube', 'Diameter':0.012, 'Length':0.012}]

 Sim.AsterFile =['thermal']

 Sim.Mesh =['mono']

 Sim.dpa=dpa

 Sim.Coolant =[{'Temperature':150, 'Pressure':5, 'Velocity':10}]

FEA thermal simulation produces the following rmed files in :file:`Output/Irradiation/Tutorials/irradiated_day1000/Aster/`

- thermal.rmed (thermal distribution across monoblock)

- thermacond.rmed (thermal conductivity distribution as a function of dpa and temperature across monoblock)

- yieldstrength.rmed (yield strength distribution as a function of dpa and temperature across monoblock)

- yieldstrength_cucrzr.rmed (yield strength distribution across CuCrZr pipe as a function of dpa and temperature across monoblock for lifecycle assessment which will be discussed in the next sections)

FEA Mechanical simulation (G)

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FEA mechanical simulations (G) are performed for tungsten monoblock by imposing the following boundary conditions:

•	Thermal stress obtained from FEA thermal simulation (C).

•	Coolant pressure.

•	Temperature dependant heat flux is derived based on the 1D modelling approach which is like that one employed for ITER cooling system.

The thermal properties such as thermal expansion coefficient, thermal conductivity and specific heat are obtained from literature. In particular, the thermal conductivity (f(dpa, temperature)) of tungsten armour are obtained from the effective thermal conductivity derived from the RVE thermal simulations (F) modelled with irradiation-induced defects. While, the thermal conductivity (f(dpa, temperature)) of copper interlayer and CuCrZr coolant pipe are obtained both from literature and based on some assumptions.

The mechanical boundary conditions imposed across the monoblock is depicted in :numref:`Fig. %s <Monoblock2>`.

.. _Monoblock2: