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This dmy may be too technical for most readers to understand.(August 2009) |
This article doesn't work at all for me, anymore. I keep getting errors, i.e.: "
A simple equation to describe Newtonian fluid behaviour is
Failed to parse (Can't write to or create math output directory): \tau=\mu\frac{dv}{dx}
where
Failed to parse (Can't write to or create math output directory): \tau
" Sim 03:15, 1 September 2006 (UTC)
The article is well and good for those who have done uni-level maths, but makes little sense at all to those who don't... compare non-Newtonian_fluid, which is very clear as to what's going on. -- User:Firien § 11:55, 3 February 2006 (UTC)
What's with the removal of the delta factor? Here - while I can't parse it completely, I think the component is the shear perpendicular to a given face (i=j) by grad velocity, which looks like a flow factor, which the shear should depend on; flagging it also because it's the only edit by that IP, and I'd like to get it verified before letting it go! -- User:Firien § 18:46, 8 February 2006 (UTC)
The article currently starts with: "A Newtonian fluid (named for Isaac Newton) is a fluid that flows like water". I find this confusing because: 1. it's not clear in what way it's supposed to flow like water, and: 2. water is not a newtonian fluid - for large stress it reacts like a solid (i.e. when an asteroid hits water, it shatters as the hydrogen bonds have no time to realign), and for small stresses there are miniscus forces (so a jesus lizard can walk on water) so the stress/rate of strain curve is not linear and doesn't go through the origin.
Also, it's not clear to me if the 'rate of strain', and the velocity gradiant that appears in the equation are the same thing.
I hope someone who considers himself qualified will rewrite the definition. 88.153.104.131 20:27, 22 July 2007 (UTC)
For a Newtonian fluid, the viscosity, by definition, depends only on temperature and pressure (and also the chemical composition of the fluid if the fluid is not a pure substance), not on the forces acting upon it.
Suggested rewrite:
By definition the viscosity of a Newtonian fluid does not depend on the forces acting upon it. For a given pure chemical substances the viscosity depends only on pressure and temperature. For a mixture the viscosity also depends on the chemical composition. —Preceding unsigned comment added by 130.86.76.10 ( talk) 21:46, 26 May 2009 (UTC)
I have added the {{ technical}} template here on the talk page because I find the introductory section too short to relay any comprehensible meaning to a lay person. __ meco ( talk) 09:29, 15 August 2009 (UTC)
When a liquid feels no more hard nor runny when it is compressed, e.g. by stirring, then it is Newtonian. Ketchup becomes more liquid as you stir it then thickens again when you stop stirring; a corn flour and water mix seems to become a solid when you try to stir it then it relaxes back to a liquid when you stop stirring; these two are non-Newtonian liquids.
When I was in elementary school my science teacher mentioned "Newtonian fluids" to the class, claiming that they had both solid and liquid characteristics and holding up Silly Putty as an example. Now that I'm all grown up I realized that she was actually referring to non-Newtonian fluids. Stonemason89 ( talk) 16:58, 17 June 2010 (UTC)
Viscous stress tensor has largely the same material as in this article and in Navier–Stokes equations#Stresses. And originally the material now in Viscous stress tensor was in viscosity. How to deal with this? To me, inclusion/merger here seems the most logical place, since the modelling of the viscous stress tensor is essential the modelling of a Newtonian fluid. -- Crowsnest ( talk) 14:09, 3 October 2012 (UTC)
The statement "Water and air are examples of (practically) Newtonian fluids, which include , and exhibit the Weissenberg effect" is contradictory because the Weissenberg effect is exhibited by non-Newtonian fluids. It should be removed. Skater00 ( talk) 21:35, 6 March 2013 (UTC)
My professors and books always explained me that the strain of a newtonian fluid is defined as follows:
Shouldn't we add a minus to this formula? — Preceding unsigned comment added by 145.94.226.124 ( talk) 10:06, 14 December 2016 (UTC)
This
level-5 vital article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||
|
This dmy may be too technical for most readers to understand.(August 2009) |
This article doesn't work at all for me, anymore. I keep getting errors, i.e.: "
A simple equation to describe Newtonian fluid behaviour is
Failed to parse (Can't write to or create math output directory): \tau=\mu\frac{dv}{dx}
where
Failed to parse (Can't write to or create math output directory): \tau
" Sim 03:15, 1 September 2006 (UTC)
The article is well and good for those who have done uni-level maths, but makes little sense at all to those who don't... compare non-Newtonian_fluid, which is very clear as to what's going on. -- User:Firien § 11:55, 3 February 2006 (UTC)
What's with the removal of the delta factor? Here - while I can't parse it completely, I think the component is the shear perpendicular to a given face (i=j) by grad velocity, which looks like a flow factor, which the shear should depend on; flagging it also because it's the only edit by that IP, and I'd like to get it verified before letting it go! -- User:Firien § 18:46, 8 February 2006 (UTC)
The article currently starts with: "A Newtonian fluid (named for Isaac Newton) is a fluid that flows like water". I find this confusing because: 1. it's not clear in what way it's supposed to flow like water, and: 2. water is not a newtonian fluid - for large stress it reacts like a solid (i.e. when an asteroid hits water, it shatters as the hydrogen bonds have no time to realign), and for small stresses there are miniscus forces (so a jesus lizard can walk on water) so the stress/rate of strain curve is not linear and doesn't go through the origin.
Also, it's not clear to me if the 'rate of strain', and the velocity gradiant that appears in the equation are the same thing.
I hope someone who considers himself qualified will rewrite the definition. 88.153.104.131 20:27, 22 July 2007 (UTC)
For a Newtonian fluid, the viscosity, by definition, depends only on temperature and pressure (and also the chemical composition of the fluid if the fluid is not a pure substance), not on the forces acting upon it.
Suggested rewrite:
By definition the viscosity of a Newtonian fluid does not depend on the forces acting upon it. For a given pure chemical substances the viscosity depends only on pressure and temperature. For a mixture the viscosity also depends on the chemical composition. —Preceding unsigned comment added by 130.86.76.10 ( talk) 21:46, 26 May 2009 (UTC)
I have added the {{ technical}} template here on the talk page because I find the introductory section too short to relay any comprehensible meaning to a lay person. __ meco ( talk) 09:29, 15 August 2009 (UTC)
When a liquid feels no more hard nor runny when it is compressed, e.g. by stirring, then it is Newtonian. Ketchup becomes more liquid as you stir it then thickens again when you stop stirring; a corn flour and water mix seems to become a solid when you try to stir it then it relaxes back to a liquid when you stop stirring; these two are non-Newtonian liquids.
When I was in elementary school my science teacher mentioned "Newtonian fluids" to the class, claiming that they had both solid and liquid characteristics and holding up Silly Putty as an example. Now that I'm all grown up I realized that she was actually referring to non-Newtonian fluids. Stonemason89 ( talk) 16:58, 17 June 2010 (UTC)
Viscous stress tensor has largely the same material as in this article and in Navier–Stokes equations#Stresses. And originally the material now in Viscous stress tensor was in viscosity. How to deal with this? To me, inclusion/merger here seems the most logical place, since the modelling of the viscous stress tensor is essential the modelling of a Newtonian fluid. -- Crowsnest ( talk) 14:09, 3 October 2012 (UTC)
The statement "Water and air are examples of (practically) Newtonian fluids, which include , and exhibit the Weissenberg effect" is contradictory because the Weissenberg effect is exhibited by non-Newtonian fluids. It should be removed. Skater00 ( talk) 21:35, 6 March 2013 (UTC)
My professors and books always explained me that the strain of a newtonian fluid is defined as follows:
Shouldn't we add a minus to this formula? — Preceding unsigned comment added by 145.94.226.124 ( talk) 10:06, 14 December 2016 (UTC)