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Total Stress Tensor

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Hi
I am trying to calculate Total Stress Tensor in a fluid.i know that:

Total Stress = -pI+Shear Stress(or viscous stress)

I want to know what this pressure is in this equation for moving fluids however this pressure is static or hydrostatic pressure for fluids at rest.


Best regards
Ram.

4 Replies Last Post 8 dic 2012, 03:35 GMT-5

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Posted: 1 decade ago 7 dic 2012, 17:06 GMT-5
Hi,
For the flowing fluid, the pressure is going to act normal to all the three directions; and for the stationary fluid, it will act only in z direction (due to gravity on earth). What happen in outer space?
Cheers
Mayur
Hi, For the flowing fluid, the pressure is going to act normal to all the three directions; and for the stationary fluid, it will act only in z direction (due to gravity on earth). What happen in outer space? Cheers Mayur

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Posted: 1 decade ago 7 dic 2012, 18:41 GMT-5
Thanks Mayur

Is it correct to say that:
Total stress (x,x)=Total stress (y,y)=Total stress (z,z)= (shear stress(x,x)+shear stress(y,y)+shear stress(z,z))/3 for moving fluids?

If so is it correct for both laminar and turbulant or newtonian and non-newtonian fluids?

Bests
Ram
Thanks Mayur Is it correct to say that: Total stress (x,x)=Total stress (y,y)=Total stress (z,z)= (shear stress(x,x)+shear stress(y,y)+shear stress(z,z))/3 for moving fluids? If so is it correct for both laminar and turbulant or newtonian and non-newtonian fluids? Bests Ram

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Posted: 1 decade ago 7 dic 2012, 22:14 GMT-5
Stresses are going to be different for laminar and turbulent flows as well as Newtonian or non-Newtonian fluids. These are the topics which can not be covered in two lines, you will find thousands of book on each of these topics.
Stresses are going to be different for laminar and turbulent flows as well as Newtonian or non-Newtonian fluids. These are the topics which can not be covered in two lines, you will find thousands of book on each of these topics.

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Posted: 1 decade ago 8 dic 2012, 03:35 GMT-5
Thanks very much Mayur
Thanks very much Mayur

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