Difference between revisions of "Friction"

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{{Stub}}
 
{{Stub}}
  
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The essence: <br>
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== Nanoscale friction ==
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The main compensating and massively overcompensating factors for rise in friction from [[higher bearing surface area of smaller machinery]] are: <br>
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* [[Convergent assembly]] not needing to fill up the whole volume in the slightest.
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== In gemstone metamaterial technology ==
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* [[Higher throughput of smaller machinery]]  
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* Plus there are some more (over)compensating factors.
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Despite [[higher bearing surface area of smaller machinery]] the [[friction in gem-gum technology]] stays manageable. <br>
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This is due to a number of effects.
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The main (over)compensating factors for rise in friction from [[higher bearing surface area of smaller machinery]] are: <br>
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* (1) [[Convergent assembly]] or equivalently ...
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* (2) [[Higher throughput of smaller machinery]] and ...
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* (X) [[Superlubricity]]
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A bit more detailed but still brief eplanations to these effects <br>
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can be found on the page [[How friction diminishes at the nanoscale]].
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== In existing nanotechnologies ==
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=== Stiff ===
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* Pretty much the only case where the above can already be experimentally tested (as of 2021) is in nested nanotubes and sliding graphene sheets.
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* At the microscale with [[MEMS]] there is the issue with [[stiction]]. Which may paint a misleading picture of how friction and wear scales when going down even further the sizescales.
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=== Soft ===
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It's hard to talk about friction is systems that are akin to biological cells. <br>
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It's obviously not that there are no energy dissipation losses.
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There necessarily are other energy devaluating mechanisms that are not "friction".
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While in thermally driven diffusion transport there is no "friction" the energy needs to be "expended" at the "pitstops" instead.
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This is necessary in order to prevent reactions and diffusion transports to run backwards.
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Stiff artificial nanosystems could be superior to nanosoft (natural and artificial) <br>
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because they may allow for more complete [[energy recuperation]] <br>
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using [[dissipation sharing]]. That is the "energetic change money" is not lost.
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== Macroscale friction ==
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=== Classical friction ===
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There is classical friction with the friction coefficient µ. <br>
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Present e.g. in dry sliding sleeve bearings.
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* This type of friction is in first approximation independent of sliding (or rolling) speed
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* This type of friction is in first approximation independent of contact area
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* This type of friction is in dependent on normal force (load)
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=== Dynamic drag ===
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There is dynamic drag in liquids and gasses. <br>
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Present e.g. in hydrostatic and hydrodynamic bearings.
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* This type of friction is dependent on speed
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* This type of friction is dependent on contact area
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* there is dependence on normal force (load) but it requires an extended model.
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=== Macroscale bearings made form gemstone based nanomachinery ===
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This is about the [[gemstone based metamaterial]] that is [[infinitesimal bearing]]s. <br>
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Distributing the speed difference over many layers can give low friction per bearing area even for higher speeds. <br>
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The rising total bearing interface are is overcompensated by the drop in friction from dropping speed. <br>
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Overall '''doubling the thickness of the stack of bearing layers halves the friction'''. <br>
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A inverse proportional linear relationship.
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Practical bearings can have quite thin stacks of bearing layers. <br>
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Thin from the human scale perspective.
  
 
== Related ==
 
== Related ==
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* Evidence of misconception: See section: "Fundamental Concepts" [https://en.wikipedia.org/w/index.php?title=Nanoelectronics&diff=775073056&oldid=770052236 Wikipedia: Nanoelectronics (2017-04-12)] (common false negatives).
 
* Evidence of misconception: See section: "Fundamental Concepts" [https://en.wikipedia.org/w/index.php?title=Nanoelectronics&diff=775073056&oldid=770052236 Wikipedia: Nanoelectronics (2017-04-12)] (common false negatives).
 
* [https://web.archive.org/web/20160322114752/http://metamodern.com/2009/02/10/nanomachines-how-the-videos-lie-to-scientists/ Nanomachines: How the Videos Lie to Scientists] ([[metamodern blog archive|Eric Drexlers metamodern blog]] (archive) 2009-02-10)
 
* [https://web.archive.org/web/20160322114752/http://metamodern.com/2009/02/10/nanomachines-how-the-videos-lie-to-scientists/ Nanomachines: How the Videos Lie to Scientists] ([[metamodern blog archive|Eric Drexlers metamodern blog]] (archive) 2009-02-10)
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__TOC__

Revision as of 11:20, 17 September 2021

This article is a stub. It needs to be expanded.

Nanoscale friction

In gemstone metamaterial technology

Despite higher bearing surface area of smaller machinery the friction in gem-gum technology stays manageable.
This is due to a number of effects.

The main (over)compensating factors for rise in friction from higher bearing surface area of smaller machinery are:

A bit more detailed but still brief eplanations to these effects
can be found on the page How friction diminishes at the nanoscale.

In existing nanotechnologies

Stiff

  • Pretty much the only case where the above can already be experimentally tested (as of 2021) is in nested nanotubes and sliding graphene sheets.
  • At the microscale with MEMS there is the issue with stiction. Which may paint a misleading picture of how friction and wear scales when going down even further the sizescales.

Soft

It's hard to talk about friction is systems that are akin to biological cells.
It's obviously not that there are no energy dissipation losses. There necessarily are other energy devaluating mechanisms that are not "friction". While in thermally driven diffusion transport there is no "friction" the energy needs to be "expended" at the "pitstops" instead. This is necessary in order to prevent reactions and diffusion transports to run backwards.

Stiff artificial nanosystems could be superior to nanosoft (natural and artificial)
because they may allow for more complete energy recuperation
using dissipation sharing. That is the "energetic change money" is not lost.

Macroscale friction

Classical friction

There is classical friction with the friction coefficient µ.
Present e.g. in dry sliding sleeve bearings.

  • This type of friction is in first approximation independent of sliding (or rolling) speed
  • This type of friction is in first approximation independent of contact area
  • This type of friction is in dependent on normal force (load)

Dynamic drag

There is dynamic drag in liquids and gasses.
Present e.g. in hydrostatic and hydrodynamic bearings.

  • This type of friction is dependent on speed
  • This type of friction is dependent on contact area
  • there is dependence on normal force (load) but it requires an extended model.

Macroscale bearings made form gemstone based nanomachinery

This is about the gemstone based metamaterial that is infinitesimal bearings.
Distributing the speed difference over many layers can give low friction per bearing area even for higher speeds.
The rising total bearing interface are is overcompensated by the drop in friction from dropping speed.
Overall doubling the thickness of the stack of bearing layers halves the friction.
A inverse proportional linear relationship.

Practical bearings can have quite thin stacks of bearing layers.
Thin from the human scale perspective.

Related

External links

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