The shear stress in turbulent flow is:a)Linearly proportional to the v...
The shear stress in turbulent flow is proportional to the square of the velocity gradient. This can be explained as follows:
Velocity gradient in turbulent flow:
In turbulent flow, the velocity of fluid particles varies randomly in all three dimensions, leading to the formation of eddies and vortices. These eddies and vortices cause fluid particles to move in different directions and at different velocities. As a result, the velocity gradient in turbulent flow is much higher than that in laminar flow.
Shear stress in turbulent flow:
Shear stress is the force per unit area acting tangentially to the surface of the object. In turbulent flow, the shear stress is caused by the exchange of momentum between fluid particles moving at different velocities. This exchange of momentum is due to the formation of eddies and vortices, which cause fluid particles to move in different directions and at different velocities.
Proportional to the square of the velocity gradient:
The shear stress in turbulent flow is proportional to the square of the velocity gradient. This can be explained by considering the momentum exchange between fluid particles in a turbulent flow. The momentum exchange is proportional to the difference in velocity between fluid particles, which is proportional to the velocity gradient. However, the momentum exchange also depends on the frequency and intensity of the eddies and vortices, which are proportional to the square of the velocity gradient. Therefore, the shear stress in turbulent flow is proportional to the square of the velocity gradient.
Conclusion:
In summary, the shear stress in turbulent flow is proportional to the square of the velocity gradient. This is due to the formation of eddies and vortices, which cause fluid particles to move in different directions and at different velocities, resulting in momentum exchange between fluid particles.
The shear stress in turbulent flow is:a)Linearly proportional to the v...
For this shear stress is proportional to square of velocity not velocity gradient which is not in option that's why I go with option c
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