L1: Stress Analysis in Mechanical Design Flashcards
What is Torsion
Twisting of a bar loaded with moments (torques) that tend to produce rotation about its long axis
How does Torsion occur and why may failure occur
Equation for Torque
How can you work out the direction of Torque on a shaft
What assumptions are made with Torsion of Circular Shafts
- Bar is in pure torsion
- Small rotations (the length and radius will not change)
How does a Circular Shaft deform when under Torsion
What happens in Uniform Torsion
- The internal torque is the same for the whole bar
- The bar has the same cross-section over the whole length
How can the relation between shear strain and angle of twist be related
How can the rate of twist of a bar be found
What are the equations for relating Shear Strain and Shear Stress to the radius of the bar
What trend does the distribution of shear strain and stress show
The distribution of shear strain and shear stress in a section of a solid and a hollow circular bar is such that stress/strain increases from zero at the centre (from minimum at inner radius) to its maximum value at the perimeter.
What is the relation between the rate of twist and the internal torque
What is the polar moment of area general equation
What is the polar moment of area for a solid circular bar
What is the polar moment of area for a hollow circular bar
What is the Torsion equation for pure torsion
Why are hollow tubes used sometimes as opposed to solid bars as torsional elements
Equation for Angle of Twist
Equation for Shear Stress for a bar under Torsion
Equation for Maximum allowed Shear Stress
Maximum allowed angle of twist between the ends
