It is defined as ratio of the product of modulus of rigidity and polar moment of inertia to the length of the shaft.
Torsional Rigidity is caluclated as: Torsional Rigidity= C J/l
ANY MACHINED BAR CAN BE CALLED AS ROD, IT TRANSFERRS MOTION FROM ONE LINK TO ANOTHER..................IF THE SUPPLIED MOTION IS OF TORSIONAL TYPE(WHICH TENDS TO ROTATE THE LINK ON ITS OWN AXIS) THE SAME ROD IS CALLED A SHAFT... RANA PRAKASH ranaprakash2873@gmail.com
A torsion testing machine is used for determining the shear stress, modulus of rigidity, strain energy, ultimate torsional stress, etc of a material. It is mainly used in the field of Mechanical Engineering. The machine consists of two jaws. One jaw is capable of rotating whereas the other jaw remains stationary. The movable jaw is driven by an electric motor which can be operated in both forward and reverse directions.
http://www.engineeringtoolbox.com/modulus-rigidity-d_946.html
stb shaft automotive
G = E/2(1+u) where G = mod of rigidity and u =poisson ration and E = young modulus
Torsional rigidity of a shaft, also known as torsional stiffness, refers to the shaft's resistance to twisting under an applied torque. It is a measure of how much the shaft twists relative to the applied torque. Torsional rigidity is important in applications where precise torque transmission is required without excessive twisting or deformation of the shaft.
inversly proportioal to cube of diameter
Torsional rigidity refers to a structure's ability to resist twisting or torsion forces, typically along its longitudinal axis. Lateral rigidity, on the other hand, pertains to a structure's resistance to lateral or side-to-side movements. In essence, torsional rigidity focuses on resisting twisting forces, while lateral rigidity focuses on resisting horizontal movements.
Force exerted from a rope tide around the catapult shaft
Torsional analysis: This analysis completed based on strcture properties like Mass MI and Torsional stiffness. Torsional critical speed analysis: Speed of rotor will come into picture in addition to Mass MI and Torsional stiffness of the structure.
One pascal is 1newton/meter^2. Therefore one megapascal is 10^6 newton/meter^2. Megapascal is a unit of Pressure (to be precise, stress) . So we cannot convert between Newton meter per degree and Megapascal as units of torsional rigidity.
In a torsion pendulum, torsional oscillations are observed. These oscillations involve the twisting of a wire or shaft that suspends the pendulum mass, resulting in a rotational motion back and forth. The restoring force for these oscillations comes from the torsional stiffness of the wire or shaft.
Torsion = turning Oscillation = repeated motion toraion oscillation is repeated turing back and forth. Imagine you have a weight hanging on the end of a piece of string. Twist the weight and, when released, it will oscillate torsionally.
1. This is due to the stress concentration at the corners of the key way and reduction in the cross-sectional area of the shaft. It, other words the torsional strength of the shaft is reduced. 2. In case the key way is too long and the key is of sliding type, then the angle of twist increased. So it is actually assumed that the strength of the keyed shaft is 75% of the solid shaft.
The modulus of rigidity of a wire can be calculated using a torsion pendulum experiment by measuring the angular deflection of the wire under a known torque. By relating the torsional constant of the wire, the length of the wire, and the applied torque, the modulus of rigidity (also known as shear modulus) can be determined using the formula G = (π * r^4 * T) / (2 * L * θ), where G is the modulus of rigidity, r is the radius of the wire, T is the torque, L is the length of the wire, and θ is the angular deflection.
ANY MACHINED BAR CAN BE CALLED AS ROD, IT TRANSFERRS MOTION FROM ONE LINK TO ANOTHER..................IF THE SUPPLIED MOTION IS OF TORSIONAL TYPE(WHICH TENDS TO ROTATE THE LINK ON ITS OWN AXIS) THE SAME ROD IS CALLED A SHAFT... RANA PRAKASH ranaprakash2873@gmail.com
The term torsional critical speed of centrifugal pumps and associated drive equipment refers to the speed of a pump rotor or related rotating system that corresponds to a resonant frequency of torsional vibration of the rotating system. Torsional critical speeds are associated with torsional or angular deflection of the rotor and are not to be confused with lateral critical speeds associated with lateral deflection. The two are separate entities. A given rotor or rotating system may possess more than one torsional resonant frequency or torsional critical speed. The lowest frequency which produces the "first mode shape" and "first torsional critical speed" is in general of the most concern. Torsional vibration is caused by torsional excitation from sources such as variable frequency drive motor toque pulsations, combustion engine torque spikes and impeller vane pass pulsation. The calculation of the first torsional critical speed is fairly simple for simple rotor systems.