- #1
dom_quixote
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Are these hydrodynamic effects the same?
B Hydrodynamics Effects: Are They the Same?
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The discussion clarifies that the Coanda effect and ram pressure are distinct hydrodynamic phenomena. The Coanda effect involves fluid flow parallel to a surface, remaining attached due to viscosity and boundary layer velocity variations. In contrast, ram pressure arises from perpendicular flow creating pressure due to unbalanced kinetic energy. Observations of a hose nozzle being "sucked in" during an experiment relate to the Bernoulli effect, where fluid velocity beneath the nozzle exceeds that above it. Understanding these principles is crucial for accurately explaining observed fluid dynamics.
- #2
Baluncore
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No, they are different effects.
Coanda effect; https://en.wikipedia.org/wiki/Coandă_effect
Ram pressure; https://en.wikipedia.org/wiki/Ram_pressure
In one, the flow is parallel to the surface and remains attached due to fluid viscosity and the velocity variation in the boundary layer.
In the other, the flow is perpendicular and provides a pressure due to unbalanced kinetic energy; KE = ½·m·v² .
Maybe you are seeing some other phenomenon. You need to explain the process you are referring to, or observing, in each case.
Coanda effect; https://en.wikipedia.org/wiki/Coandă_effect
Ram pressure; https://en.wikipedia.org/wiki/Ram_pressure
In one, the flow is parallel to the surface and remains attached due to fluid viscosity and the velocity variation in the boundary layer.
In the other, the flow is perpendicular and provides a pressure due to unbalanced kinetic energy; KE = ½·m·v² .
Maybe you are seeing some other phenomenon. You need to explain the process you are referring to, or observing, in each case.
- #3
dom_quixote
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Thanks Baluncore!
I did a variation of the second experiment with a bucket. I did not film the experiment due to the difficulty of observing the phenomenon. However, the hose nozzle is also "sucked in" even when the water level rises. Would it be the same effect "RAM Pressure"?
I did a variation of the second experiment with a bucket. I did not film the experiment due to the difficulty of observing the phenomenon. However, the hose nozzle is also "sucked in" even when the water level rises. Would it be the same effect "RAM Pressure"?
- #4
Lnewqban
Homework Helper
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Then, for the second part of the video you were referring to the sucking effect between hose end and flat lid.dom_quixote said:
This happens because the Bernoulli effect, as the fluid velocity under the hose nozzle is greater than the one above.
Please, see:
https://en.wikipedia.org/wiki/Bernoulli's_principle
Power = Force v Speed
Power of my horse = 104kgx9.81m/s^2 x 0.732m/s = 1HP =746W
Force/tension in rope stay the same if horse run at 0.73m/s or at 15m/s, so why then horse need to be more powerfull to pull at higher speed even if backward force at him(rope tension) stay the same?
I understand that if I increase weight, it is hrader for horse to pull at higher speed because now is backward force increased, but don't understand why is harder to pull at higher speed if weight(backward force)...
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