Share good ideas and conversation.   Login, Join Us, or Take a Tour!
comment by ThatFanficGuy
ThatFanficGuy  ·  763 days ago  ·  link  ·    ·  parent  ·  post: Pubski: June 14, 2017

A wonder, then, why it hasn't been developed to a more endurant level. Humanity starts a "new level" of something whenever there's the abundance of resource and workforce for it, isn't that true? Maybe we're just waiting for graphene to become mass product... but then, we'll just suffer over it not working in zero-G or something. :)

Fluid bearing made no sense to me 'cause it's late and my brain is tired. If you could ELI5 it for me, that would be appreciated.




kleinbl00  ·  763 days ago  ·  link  ·  

Mechanical objects cannot follow Moore's Law. Newtonian physics has been a settled thing for 200 years now and while we can make improvements in materials science, the equations that govern mechanical design have no shortcuts.

A fluid bearing uses a fluid (in physics terms, this means either a liquid or a gas) to absorb the shock of impact and friction. The design of the bearing is dependent on the viscosity and other properties of the fluid. Basically, if you have two parts that should have friction between them, and put a layer of properly designed fluid in between, the friction between those parts becomes the friction between the fluid and the surface instead of the two surfaces.

The archetypal example is a connecting rod and a crankshaft journal:

In a fluidless scenario, the impact of the exploding gas on the piston is transferred down the connecting rod to the crankshaft and the inner diameter of the rod and the outer diameter of the crankshaft rub together, make lots of heat and wear. In a fluid bearing scenario, the impact from combustion is absorbed by the fluid, which has much lower friction than the two metal surfaces, and which is also under constant replacement by the oil pump. This allows the friction heat of the surfaces to be removed from the site.

That was more ELI10 but that's the idea.

ThatFanficGuy  ·  759 days ago  ·  link  ·  

It took me a while, but I got there.

Thanks for the explanation - as well as for reminding me why I'm not in engineering.

goobster  ·  763 days ago  ·  link  ·  

(I will not nitpick that Newtonian physics existed long before Newton. I will not nitpick that Newtonian physics existed long before Newton. I will not nitpick that Newtonian physics existed long before Newton. I will not nitpick that Newtonian physics existed long before Newton.)

kleinbl00  ·  763 days ago  ·  link  ·  

the equations didn't

goobster  ·  762 days ago  ·  link  ·  

Well, that's kinda what I was getting at, philosophically.

Technically, the equations just are a way of describing the phenomena or principle. So in a way, Newtonian Physics are only the equations describing the principles. So sure, those principles existed before he described them in mathematical calculations.

I dunno... I'm sitting in a long and boring conference call/training, and my mind is wandering off into the weeds... government contracting, my friends... my brains are leaking out my ears...

bfv  ·  762 days ago  ·  link  ·  

    I dunno... I'm sitting in a long and boring conference call/training, and my mind is wandering off into the weeds... government contracting, my friends... my brains are leaking out my ears...

I know your pain.

kleinbl00  ·  762 days ago  ·  link  ·  

That video is appropriate far too much of the time.

kleinbl00  ·  762 days ago  ·  link  ·  

Philosophically, sure. But if you want to act on it, you have to know it, and that knowledge isn't eternal.

My bicycle has 27 speeds and tires that run at 90psi. None of the physical laws that governed its construction came into being recently. But without the knowledge of metallurgy, chemistry, manufacturing science and materials technology that have been developed in the past 100 years it'd be a velocipede. I mean, carbon fiber spokes. Beat steel in many many ways, but utterly unheard of 40 years ago. Multiply by everything. However, hydrodynamic bearings? That's steam engine shit. Internal combustion has advanced much slower than semiconductors despite the fact that the laws of the universe have been knowable (but unknown) since its birth.

ThatFanficGuy  ·  763 days ago  ·  link  ·