Quick Points Fluids/Solids Velocity Speed

[ohitsthatguy]

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Ok so I've studied the fluids and solids concepts and I just want to confirm that my understanding is correct overall:
Fluids are generally faster:
-with a smaller area/narrower pipe (A1v1=A2v2 )
-middle of the pipe (effects of drag least)
-shorter the pipe (longer pipes create more resistance)
-less pressure (such as against a plane wing, velocity is faster on the side with less pressure)

Is this all correct? Please add any points that yall think I have missed!

 

[inasensegone]

Most of this seems relatively correct (in the correct situation) except for the last point. That one needs a better definition:

-less pressure (such as against a plane wing, velocity is faster on the side with less pressure)

Velocity of the fluid is faster with a greater pressure difference. If there is high pressure behind the fluid, and low pressure at the end of the pipe, the fluid flows to the end more quickly.

Also, with your airplane wing example, I think you are misinterpreting Bernoulli's Principle. It is the increased velocity of the fluid, that is the cause of the low pressure. As the velocity of the fluid increases, the pressure it exerts on the airplane wing decreases (or the walls of a pipe). This is why the air on the top of the wing has lower pressure, because the air travels faster over the top of the air wing. The lower pressure on top of the wing, causes the air on the bottom of the wing to "push up" on the wing from below. The lower velocity of blood at the level of our capillaries also allows for a greater force exerted on the walls of our capillaries (hence, filtration via the hydrostatic pressure)

Here is a quick video I found that very briefly covers Bernoulli's principle in regards to airplane wings. It also describes how Bernoulli's principle alone cannot explain the principle of airplane flight.

 

[ohitsthatguy]

Oh alrighty, glad I was on the right track. I had it the opposite way I guess. Instead of velocity just being faster on a side with less pressure, it is actually more of a direct relation where the increased velocity will cause less pressure against the sides. Thanks a lot though, much appreciated!