Quote:
Originally Posted by JulianEdgar
I think I skimmed through that video a while ago.
In general it's not worth getting excited about laminar and turbulent flow. Very little airflow on a normal car is technically laminar, and so looking at things in terms of laminar and turbulent flows tends to lead people astray ie create confusion.
I think it's much better to concentrate on separated and attached flows.
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1) Most of the 'flow' on an automobile is 'laminar.'
2) Most of the aerodynamic drag of an automobile is pressure drag.
3) Pressure drag is a function of flow separation.
4) Separation creates 'turbulence' and it's associated low pressure which affects base pressure, which is directly associated with pressure drag.
5) The entire premise of automotive streamlining has to do with reducing or eliminating turbulence, via reducing, or eliminating separation.
6) 'Turbulence' is very much worth getting excited about. By default.
7) Confusion will come from not being able to distinguish the distinction between ' boundary layer' conditions, and outer, 'inviscid' flow conditions. Very different animals.
8) So while it IS important to concentrate on 'separated' and 'attached' flows, we do it because of the implications of laminar or turbulent flow.
9) Finally, it's also important to consider the implications of turbulence in connection to 'lift.' Worthy of it's own thread.