Convection: Realising a Trivial Thing?

[vin300]

Realising that all is not well when we're just moving not thinking, I began to think about a trivial thing which has been around me for too long. What actually is convection? If it is governed by difference in density causing the masses to flow, is this not atleast distantly, similar to a pressure wave?

 

[BvU]

You may want to ask a more specific (detail) question after having looked at wikipedia (or this ) .

I see little reason to re-hash what it says there.

It's not similar to a pressure wave: there is no restoring force, hence no wave character involved.

 

[boneh3ad]

You may want to ask a more specific (detail) question after having looked at wikipedia (or this ) .

I see little reason to re-hash what it says there.

It's not similar to a pressure wave: there is no restoring force, hence no wave character involved.

There absolutely can be a wave character involved (e.g. Rayleigh-Bénard convection). However, it's not the same as a pressure wave.

 

[HallsofIvy]

Convection refers to some property (temperature, pressure, etc.) of a gas or liquid moving because the molecules of the gas or liquid themselves move.

 

[vin300]

In a pressure wave the average location of particles is the same, however, in some forms of convection too, the average location is the same, but motion is non linear. The temperature causes pressure that extends, whereas gravity effect differences cause forces that restore. I guess forced convection is farther from what could be seen an harmonic behaviour.

 

[vin300]

The clear distinction is that pressure travel is governed by a property purely possessed by the medium, while here it depends on properties of outside bodies that affect motion.