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thetexan
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Are all fluids incompresible? If not, what is the attribute that allows any compressible fluid to do so while others, such as hydraulic fluid to not?
tex
tex
No. Air is compressible.thetexan said:Are all fluids incompresible?
The word fluid includes liquids and gases. All fluids have some level of compressibility. The term incompressibity is an ideal limit of small, but finite, compressibility, and is often an excellent approximation.thetexan said:Are all fluids incompresible? If not, what is the attribute that allows any compressible fluid to do so while others, such as hydraulic fluid to not?
tex
Surethetexan said:So I should have used the work liquids. So, all liquids have "some" compressibility? Even hydraulic oil?
tex
Look up tables showing the property called 'bulk modulus' for various liquids. It's the inverse of compressibility. While in mechanical applications higher bulk modulus means you're losing less power on compressing the liquid, it's not always worth the effort of going for exotic substances (I don't think anybody is using mercury in their hydraulics, despite its superior bulk modulus).thetexan said:So I should have used the work liquids. So, all liquids have "some" compressibility? Even hydraulic oil?
tex
Can you please give a specific reaction example where the fluid dynamics are affected in a liquid phase system?DrDu said:This is also a question of what you are interested in. When you are talking about calculating the aerodynamics of a boat, the assumption of water to be incompressible is certainly excellent. If you are doing chemical reactions in an autoclave at 100 kbar, it might turn out to be rather poor.
I think the OP was referring specifically to fluid dynamic considerations.DrDu said:Not the fluid dynamics but the chemical reaction.
I had this article in mind (sorry, German only):
http://onlinelibrary.wiley.com/doi/10.1002/ciuz.19890230205/full
May be, I just wanted to indicate that the notion of whether a substance is compressible or not may be different between a naval engineer and a guy simulating nuclear bombs.Chestermiller said:I think the OP was referring specifically to fluid dynamic considerations.
For a fluid to be considered incompressible, it means that its volume does not change significantly under the application of external forces or pressure. In other words, the fluid's density remains constant even when pressure is applied to it.
No, not all liquids are considered incompressible. Some liquids, such as water, have very low compressibility and can be considered incompressible for most practical purposes. However, other liquids, such as oils or gases, have higher compressibility and cannot be considered incompressible.
The main difference between an incompressible fluid and a compressible fluid is their response to external forces or pressure. Incompressible fluids have a constant density, while compressible fluids can change in density when pressure is applied.
Knowing whether a fluid is incompressible is important in many fields of science and engineering, such as fluid mechanics, aerodynamics, and hydraulics. Incompressible fluids behave differently than compressible fluids, and understanding this difference can help in the design and analysis of various systems and processes.
No, there is no such thing as a completely incompressible fluid. While some fluids, like water, may have very low compressibility, they will still undergo some change in density when pressure is applied. However, for practical purposes, these fluids can be considered incompressible due to their negligible change in density.