Shear stress direction and the velocity gradient

Thread starter Rahulx084
Start date Feb 6, 2019
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Direction Fluid flow Fluid force Gradient Shear Shear force Shear stress Stress Velocity

In summary, the conversation discusses the direction of stress in a flowing fluid and how it affects different elements within the fluid. It mentions the Cauchy stress relationship and the stress tensor as tools to determine stress on a surface of arbitrary orientation. The conversation also touches on the concept of a stress vector and its components in different directions.

Feb 9, 2019

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Rahulx084 said:

can you just give me the result for stress tensor of cubical and parallelopiped one ? It would be so nice of you . Thanks

See Eqns. 43 of that same reference.

<h2>1. What is shear stress direction?</h2><p>Shear stress direction refers to the direction in which a force is applied to an object, causing it to deform or change shape. In the context of velocity gradient, it is the direction in which the fluid is moving relative to the surface of an object.</p><h2>2. How is shear stress direction related to velocity gradient?</h2><p>Shear stress direction and velocity gradient are closely related because the velocity gradient is the change in velocity over a given distance, and the direction of this change determines the direction of the shear stress. In other words, the velocity gradient determines the direction of the shear stress.</p><h2>3. What is the significance of shear stress direction in fluid mechanics?</h2><p>Shear stress direction is important in fluid mechanics because it affects the flow behavior of fluids. The direction of shear stress can determine the type of flow (e.g. laminar or turbulent) and can also impact the efficiency of fluid flow in pipes and channels.</p><h2>4. How is shear stress direction measured?</h2><p>Shear stress direction can be measured using various instruments such as a strain gauge, a viscometer, or a rheometer. These instruments measure the force or strain on a surface and can determine the direction of the shear stress.</p><h2>5. Can the shear stress direction be changed?</h2><p>Yes, the shear stress direction can be changed by altering the velocity gradient. For example, if the velocity gradient is increased in a certain direction, the shear stress will also increase in that direction. This can be achieved by changing the shape of the object or by changing the properties of the fluid, such as its viscosity.</p>

FAQ: Shear stress direction and the velocity gradient

1. What is shear stress direction?

Shear stress direction refers to the direction in which a force is applied to an object, causing it to deform or change shape. In the context of velocity gradient, it is the direction in which the fluid is moving relative to the surface of an object.

2. How is shear stress direction related to velocity gradient?

Shear stress direction and velocity gradient are closely related because the velocity gradient is the change in velocity over a given distance, and the direction of this change determines the direction of the shear stress. In other words, the velocity gradient determines the direction of the shear stress.

3. What is the significance of shear stress direction in fluid mechanics?

Shear stress direction is important in fluid mechanics because it affects the flow behavior of fluids. The direction of shear stress can determine the type of flow (e.g. laminar or turbulent) and can also impact the efficiency of fluid flow in pipes and channels.

4. How is shear stress direction measured?

Shear stress direction can be measured using various instruments such as a strain gauge, a viscometer, or a rheometer. These instruments measure the force or strain on a surface and can determine the direction of the shear stress.

5. Can the shear stress direction be changed?

Yes, the shear stress direction can be changed by altering the velocity gradient. For example, if the velocity gradient is increased in a certain direction, the shear stress will also increase in that direction. This can be achieved by changing the shape of the object or by changing the properties of the fluid, such as its viscosity.