Cooling

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Cooling is both relevant in both

  • mundane and important practical systems and
  • especially in systems that aim to go to the absolute limits of what is possible

The latter by nature goes in quite speculative territory as
it is not compatible with conservative estimation and exploratory engineering.

The latter relates to a common misconception about the limits of power density:
Taking stated numbers too literally See page: Limits of power density imposed by limits of cooling

Practical cooling in gem-gum factories

Heat that needs to be removed originates from:

  • dissipation from (more or less intentional) snapping instabilities
  • more subtle inefficiencies in piezomechanosynthesis
  • frictive dissipation – Only partly recuperable by heat engine due to conversion of free energy into bound energy.
  • squeeze-out of entropy – heat from moving disorder in positional space to disorder in impulse space (aka heat) (fully recuperable)

Temperatures to cool to:
For reliability of piezomechanosynthesis lower is better.
Below some point there are diminishing returns though.
Optimal might likely be somewhere around liquid nitrogen. Maybe a bit lower.
Room-temperature works bit is a bit too high for good reliability.
Liquid helium temperatures are likely overkill.

Anticooling (i.e. energy recuperative warming/heating):
To get the energy back that was invested to cool below room temperature and
to not freeze clean room air in further up assembly levels
the so far assembled parts-fragments need to be warmed up again before proceeding to higher assembly levels that
no longer involve (unguided) aligning of atomic bonds.
Basically one needs to recuperate the cooling energy by heat engine.

Given layer geometry of assembly level (assembly layers) as a possible self suggesting geometry
cooling and anticooling forms a "cooling sandwich".
From an surface to volume ratio this thin layer sandwich geometry is far from optional.
Maybe hinting on that an other more batch processing
and serializing in-between geometry might be worth considering.
Increasing fast track transport distances increases frictive losses though so its a tradeoff optimization.
Also depending on how efficient piezomechanosynthesis can be made as it likely dominates over frictive losses.

(TODO: Investigate possible assembly level geometries taking this into account too.)

Taking cooling to its limit

See main page: The limits of cooling

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