Update first wall variables for clarity

[chris-ashe]

Description

Update the First Wall (FW) variables to be more verbose and meet the new style guide. This should make the code easier to understand.

• New style guide unit for component lifetime with the life_ prefix.
• New style guide unit for fluid viscosity with the visc_ prefix.

Namespace changes

Functions

---

Variables

• afw -> radius_fw_channel
• fw_wall -> dr_fw_wall
• pitch -> dx_fw_module : Since this is the distance between adjacent FW cooling pipes or more simply the width of each seperate FW cooled segment the dx_ prefix has been used as the direction is not in a single dimension.
• fwith -> dr_fw_inboard : Now more clearly shows that it is the radial thickness
• fwoth -> dr_fw_outboard : Now more clearly shows that it is the radial thickness
• 🔥 denw: Removed from fwbs_variables and added as new variable den_tungsten into constants.py
• iblanket -> i_blanket_type: More explicitly shows that this is the type of blanket system chosen instead of possible being a switch for the presence of a blanket.
• fwinlet -> temp_fw_coolant_in: Makes this more explicit that this is the coolant temperature instead of the FW structure
• fwoutlet -> temp_fw_coolant_out: Makes this more explicit that this is the coolant temperature instead of the FW structure
• fwpressure -> pres_fw_coolant: Makes this more explicit that this is the coolant pressure
• fwareaib -> a_fw_inboard: Changed to meet new style guide
• fwareaob -> a_fw_outboard: Changed to meet new style guide
• fwarea -> a_fw_total: Changed to make it more explicit that it is the sum of the inboard and outboard FW areas.
• volfw -> vol_fw_total: Changed to make it more explicit that it is the sum of the inboard and outboard FW volumes.
• vffwo -> f_a_fw_coolant_outboard: Make it easier to show that this is the fraction of the FW cross-sectional area taken by the coolant pipes.
• vffwi -> f_a_fw_coolant_inboard: Make it easier to show that this is the fraction of the FW cross-sectional area taken by the coolant pipes.
• fwmass -> m_fw_total: Make it easier to show that this is the total mass of both first walls.
• fwcoolant -> i_fw_coolant_type : Add switch i_ prefix and make it easier to discern if this is choosing the presence of a FW coolant or its type (incase an inertially cooled FW is a future option).
• fwlife -> life_fw_fpy
• pnucfw -> p_fw_nuclear_heat_total_mw
• fw_channel_length -> len_fw_channel
• tpeak -> temp_fw_peak
• tfwmatmax -> temp_fw_max
• rhof_fw -> den_fw_coolant
• visc_fw -> visc_fw_coolant
• peaking_factor -> f_fw_peak

---

✨ New additions

• den_tungsten : Now added to constants.f90

---

🐛 Bugs

Checklist

I confirm that I have completed the following checks:

• My changes follow the PROCESS style guide
• I have justified any large differences in the regression tests caused by this pull request in the comments.
• I have added new tests where appropriate for the changes I have made.
• If I have had to change any existing unit or integration tests, I have justified this change in the pull request comments.
• If I have made documentation changes, I have checked they render correctly.
• I have added documentation for my change, if appropriate.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 50.46729% with 53 lines in your changes missing coverage. Please review.
✅ Project coverage is 31.55%. Comparing base (7db8627) to head (724c025).
⚠️ Report is 479 commits behind head on main.

Files with missing lines	Patch %	Lines
process/stellarator.py	11.76%	15 Missing ⚠️
process/blanket_library.py	37.50%	10 Missing ⚠️
process/power.py	0.00%	8 Missing ⚠️
process/build.py	0.00%	6 Missing ⚠️
process/io/sankey_funcs.py	0.00%	4 Missing ⚠️
process/caller.py	0.00%	3 Missing ⚠️
process/output.py	0.00%	3 Missing ⚠️
process/costs.py	66.66%	1 Missing ⚠️
process/fw.py	95.45%	1 Missing ⚠️
process/hcpb.py	88.88%	1 Missing ⚠️
... and 1 more

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3502   +/-   ##
=======================================
  Coverage   31.55%   31.55%           
=======================================
  Files          82       82           
  Lines       19565    19565           
=======================================
  Hits         6173     6173           
  Misses      13392    13392           

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[timothy-nunn]

Just one thing missing from the obsolete_variables I think

[timothy-nunn]

Happy with code and docs changes.

[OceanNuclear]

(Typo on iblanket? (iblnaket))

[chris-ashe]

(Typo on iblanket? (iblnaket))

Yes, small typo. Have corrected