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General Discussion => Q&A Section => Topic started by: rakaydos on 02/10/2021 12:22 am

Title: Convection in Spin Gravity?
Post by: rakaydos on 02/10/2021 12:22 am
So a comment in another thread pointed out that in zero G you cannot rely on Convection to distribute heat from the sunny side of a spacecraft to the shaded side.

But what about in a rotational frame or reference? A classic BBQ roll is one example, but it also obviates the problem for obvous reasons... but what about a spin, axis on to the sun, like was proposed for the Von Br- I mean, Voyager station?

What would convection look like across a thermal gradient, inside a rotational frame of reference, axis aligned with the heat source?
Title: Re: Convection in Spin Gravity?
Post by: Jim on 02/12/2021 12:48 pm
So a comment in another thread pointed out that in zero G you cannot rely on Convection to distribute heat from the sunny side of a spacecraft to the shaded side.

But what about in a rotational frame or reference? A classic BBQ roll is one example, but it also obviates the problem for obvous reasons... but what about a spin, axis on to the sun, like was proposed for the Von Br- I mean, Voyager station?

What would convection look like across a thermal gradient, inside a rotational frame of reference, axis aligned with the heat source?

That is true within a pressurized volume.  Convection doesn't work in a vacuum because there no medium (air, water, etc) to transfer the heat.  Conduction still works on a rotation body.  Also, forced convention works (coolant lines, air ducts, etc).  Within a large rotating pressurized body, local convention works. Warmer, less dense air is going to be replaced by denser cooler air in a gravity field.