Search results
Results From The WOW.Com Content Network
When an element of mass is offset from the axis of rotation, centrifugal force will tend to pull the mass outward. The elastic properties of the shaft will act to restore the “straightness”. If the frequency of rotation is equal to one of the resonant frequencies of the shaft, whirling will occur. In order to save the machine from failure ...
Stiffness of the shaft and its support; Total mass of shaft and attached parts; Unbalance of the mass with respect to the axis of rotation; The amount of damping in the system; In general, it is necessary to calculate the critical speed of a rotating shaft, such as a fan shaft, in order to avoid issues with noise and vibration.
Some large turboprop engines, such as the original Bristol Proteus and the modern TP400 have free turbines. The TP400 is a three-shaft design, with two compressor turbines and a separate power turbine. Where the turbine is at the rear of the engine, a turboprop engine requires a long drive shaft forwards to the propeller reduction gearbox. Such ...
The angle domain equations above show that the motion of the piston (connected to rod and crank) is not simple harmonic motion, but is modified by the motion of the rod as it swings with the rotation of the crank.
For example, an inline-four engine has a vertical vibration (at twice the engine speed). These imbalances are inherent in the design and unable to be avoided, therefore the resulting vibration needs to be managed using balance shafts or other NVH-reduction techniques to minimise the vibration that enters the cabin.
The major axis of the flex spline's ellipse rotates with wave generator, so the points where the teeth mesh revolve around the center point at the same rate as the wave generator's shaft. The key to the design of the strain wave gear is that there are fewer teeth (often for example two fewer) on the flex spline than there are on the circular ...
Rotating shaft unbalanced by two identical attached weights, which causes a counterclockwise centrifugal couple Cd that must be resisted by a clockwise couple Fℓ = Cd exerted by the bearings. The figure is drawn from the viewpoint of a frame rotating with the shaft, hence the centrifugal forces.
The crankshaft is a rotating shaft containing one or more crankpins, [1] that are driven by the pistons via the connecting rods. [2] The crankpins are also called rod bearing journals, and they rotate within the "big end" of the connecting rods. Most modern crankshafts are located in the engine block.