Question on hoop stress tension in rotating objects

Thread starter paulsterx
Start date Nov 17, 2021
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Centrifugal force Rotating Stress Tension Tension force

In summary, the conversation discusses the concept of hoop stress, which arises from internal forces resisting deformation caused by radial forces in a spinning object. There is a debate about whether a greater inward force opposing the radial centrifugal force would result in compression or tension in the hoop stress. The respondent believes that hoop stress is produced by radial forces, and if an opposing force is greater than the centrifugal force, there would be net compression instead of tension. The other person believes that hoop stress is produced through some other means and would still occur even with a greater inward force.

Feb 26, 2022

Chestermiller

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LT Judd said:

Hi Chester,
Sorry for the late reply, I wanted to have a long think about it. Yes I am familiar with polar co-ordinates and unit vectors , but I dare say not as much as you are. I just struggled with some of your notations and sign conventions.

Anyhow , I decided to look at this another way however and realized that I should have accounted for gravity in my FBD as it turn out that has a far greater effect that an any centripetal force or hoop stress.

You are aware that you can cause a ring to rotate about its axis as fast as you want, and this can create centripetal accelerations far exceeding g, with associated huge hoop tensions, right?

<h2>1. What is hoop stress tension in rotating objects?</h2><p>Hoop stress tension is a type of stress that occurs in objects that are subjected to rotational forces. It is caused by the centrifugal force, which pulls the object outward from its center, creating tension along the circumference of the object.</p><h2>2. How is hoop stress tension calculated?</h2><p>Hoop stress tension can be calculated using the formula σ = ρω²r, where σ is the hoop stress tension, ρ is the density of the object, ω is the angular velocity, and r is the distance from the center of rotation to the outer edge of the object.</p><h2>3. What are the effects of hoop stress tension on rotating objects?</h2><p>Hoop stress tension can cause deformation or failure in rotating objects if the stress exceeds the object's strength. It can also cause cracks or fractures along the circumference of the object.</p><h2>4. How can hoop stress tension be reduced?</h2><p>Hoop stress tension can be reduced by increasing the object's strength, decreasing the rotational speed, or increasing the distance from the center of rotation to the outer edge of the object.</p><h2>5. What are some real-world examples of hoop stress tension?</h2><p>Hoop stress tension can be observed in various rotating objects, such as wheels, gears, turbines, and flywheels. It is also a critical factor in the design of structures such as bridges and wind turbines.</p>

1. What is hoop stress tension in rotating objects?

Hoop stress tension is a type of stress that occurs in objects that are subjected to rotational forces. It is caused by the centrifugal force, which pulls the object outward from its center, creating tension along the circumference of the object.

2. How is hoop stress tension calculated?

Hoop stress tension can be calculated using the formula σ = ρω²r, where σ is the hoop stress tension, ρ is the density of the object, ω is the angular velocity, and r is the distance from the center of rotation to the outer edge of the object.

3. What are the effects of hoop stress tension on rotating objects?

Hoop stress tension can cause deformation or failure in rotating objects if the stress exceeds the object's strength. It can also cause cracks or fractures along the circumference of the object.

4. How can hoop stress tension be reduced?

Hoop stress tension can be reduced by increasing the object's strength, decreasing the rotational speed, or increasing the distance from the center of rotation to the outer edge of the object.

5. What are some real-world examples of hoop stress tension?

Hoop stress tension can be observed in various rotating objects, such as wheels, gears, turbines, and flywheels. It is also a critical factor in the design of structures such as bridges and wind turbines.