How Do Air Bubbles Affect Viscosity in High Viscosity Fluids?

AI Thread Summary
Air bubbles in high viscosity fluids can affect the overall density but typically do not change the viscosity unless the air content is significant enough to alter the fluid's characteristics. The discussion emphasizes the need to clarify which type of viscosity is being referenced, particularly dynamic viscosity. It is noted that the macroscopic viscosity of a fluid with air bubbles will generally be lower than that of the pure liquid. The presence of air can make the fluid lighter, which is why mixers are often used in tanks. Ultimately, the relationship between air bubbles and viscosity is complex and depends on the specific conditions of the fluid mixture.
ZdMh
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Is a high viscosity fluid(liquid), filled with air bubbles, more or less vicious than without air? Please provide the scientific principle behind that
 
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Air bubbles should affect density, but viscosity of the fluid itself should remain the same, unless the amount of mixed air is big and sufficient to modify the characteristics of the mix.
Let’s wait for other posts.
 
Viscosity is an ill-defined term and before this discussion slides off the rails, it is important to specify which of the various "types" of viscosity is being discussed. In my experience they are largely defined by the experiments used to measure them.
https://en.wikipedia.org/wiki/Viscosity#Definition
 
hutchphd said:
Viscosity is an ill-defined term and before this discussion slides off the rails, it is important to specify which of the various "types" of viscosity is being discussed. In my experience they are largely defined by the experiments used to measure them.
https://en.wikipedia.org/wiki/Viscosity#Definition
Of course I meant the Dynamics viscosity not the kinematic
 
Lnewqban said:
Air bubbles should affect density, but viscosity of the fluid itself should remain the same, unless the amount of mixed air is big and sufficient to modify the characteristics of the mix.
Let’s wait for other posts.
Yes maybe; because my friend said to me "if the fluid has too much air bubbles it will be lighter therefore we use a mixer in tanks"... but I'm not sure yet of this info
 
ZdMh said:
Is a high viscosity fluid(liquid), filled with air bubbles, more or less vicious than without air? Please provide the scientific principle behind that
The macroscopic viscosity of this mixture will, of course, be less than the pure liquid alone. Just consider the limit of 100% gas.
 
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