- #36
Freixas
- 307
- 41
Ok, I've had two smart people tell me this when I asked whether the pressure difference at entrance and exit meant total or static. My guess was total; the correct answer is static:
Here's my thought experiment:
boneh3ad said:Static. Static is always the relevant pressure when talking about the force on a fluid element.
Here's my thought experiment:
- I take a tube, sealed at both ends with air at 1 atmosphere. Clearly, there is no flow.
- I take it outside, where the static pressure is also 1 atmosphere, but where there is a steady breeze--remarkably steady, really.
- I line up the tube so it points into the wind.
- I remove the end caps.