Do fluid oscillation characteristics depend on the viscosity of a fluid?

In summary, viscosity has a significant impact on the oscillation of fluid inside a drinking straw.Higher viscosities cause more resistance to the flow of the fluid, while lower viscosities cause less resistance. Additionally, a spring mass damper system assumes that the damping force is proportional to the velocity. This information was helpful in understanding the relationship between viscosity and the oscillation of fluid in a drinking straw.
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tahskanaij
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Are there any equations relating the viscosity of fluids to any kinematic variables (velocity, acceleration, kinetic energy)?
This is my first thread here, so let me know if I didn't adhere to a format i was to follow. I'm in the middle of a project depicting the change that an oscillation of fluid inside a drinking straw faces depending on the viscosity of the liquid.
For reference, this is exactly the same example I'm using: https://aapt.scitation.org/doi/abs/10.1119/1.5095945?journalCode=ajp

The papers included all did their tests at extremely low viscosities, ≈0.5 to 1 cp, so I couldn't seem to find any relation over there. Essentially, what I need to do is corellate the amplitude of my oscillation, as well as the damping factor to the viscosity of that liquid. I've done the testing and there is considerable difference between 2 and 20 cp. I can make a mathematical relationship easily, but in order to hypothesize first I need to depict the known relationships between viscosity and what it may impact.

Any help would be greatly appreciated.
 
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First, study the definition of viscosity (search term). Wikipedia is a good place to start. Note how the fluid shear stress is proportional to the fluid velocity gradient. Then, in a situation such as fluid flowing through a straw, the resistance to flow must be proportional to fluid velocity.

Then study a spring mass damper system (search term). Note the assumption of damping force being proportional to velocity. Compare to the definition of viscosity. Note that the fluid in the straw has a mass, and that there is a force proportional to fluid displacement from the equilibrium position. Compare to the definition of a spring in a spring mass damper system.

For higher viscosity fluids, look into underdamped, critically damped, and overdamped systems.

Enjoy.
 
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jrmichler said:
First, study the definition of viscosity (search term). Wikipedia is a good place to start. Note how the fluid shear stress is proportional to the fluid velocity gradient. Then, in a situation such as fluid flowing through a straw, the resistance to flow must be proportional to fluid velocity.

Then study a spring mass damper system (search term). Note the assumption of damping force being proportional to velocity. Compare to the definition of viscosity. Note that the fluid in the straw has a mass, and that there is a force proportional to fluid displacement from the equilibrium position. Compare to the definition of a spring in a spring mass damper system.

For higher viscosity fluids, look into underdamped, critically damped, and overdamped systems.

Enjoy.
Thank you so much! You directed me to the right place. I was surprised to find the solution to my problems on the Wikipedia page for viscosity itself. Next time onward, before starting a concept i'll read it's wiki first.
 
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1. What is fluid oscillation?

Fluid oscillation refers to the back-and-forth movement of a fluid due to an external force or disturbance.

2. How is viscosity related to fluid oscillation?

Viscosity is the measure of a fluid's resistance to flow. It affects the rate at which a fluid oscillates, as higher viscosity fluids will oscillate at a slower rate compared to lower viscosity fluids.

3. Can fluid oscillation occur in all types of fluids?

Yes, fluid oscillation can occur in all types of fluids, including liquids and gases. However, the characteristics and behavior of the oscillations may vary depending on the viscosity of the fluid.

4. How does the viscosity of a fluid affect the amplitude of fluid oscillation?

The viscosity of a fluid can affect the amplitude of fluid oscillation by influencing the energy dissipation within the fluid. Higher viscosity fluids will dissipate more energy, resulting in smaller amplitudes, while lower viscosity fluids will have larger amplitudes.

5. Is there a mathematical relationship between viscosity and fluid oscillation?

Yes, there is a mathematical relationship between viscosity and fluid oscillation. It is described by the Stokes' law, which states that the force required to maintain a constant velocity of a sphere moving through a fluid is directly proportional to the viscosity of the fluid and the sphere's radius.

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