palmgren_miner_linear_damage¶

class
reliability.PoF.
palmgren_miner_linear_damage
¶ Uses the PalmgrenMiner linear damage hypothesis to find the outputs:
Inputs:  rated life  an array or list of how long the component will last at a given stress level  time_at_stress  an array or list of how long the component is subjected to the stress that gives the specified rated_life  stress  what stress the component is subjected to. Not used in the calculation but is required for printing the output. Ensure that the time_at_stress and rated life are in the same units as the answer will also be in those units
Outputs:  Fraction of life consumed per load cycle  service life of the component  Fraction of damage caused at each stress level
Example usage: Ball bearings are fail after 50000 hrs, 6500 hrs, and 1000 hrs, after being subjected to a stress of 1kN, 2kN, and 4kN respectively. If each load cycle involves 40 mins at 1kN, 15 mins at 2kN, and 5 mins at 4kN, how long will the ball bearings last?
palmgren_miner_linear_damage(rated_life=[50000,6500,1000], time_at_stress=[40/60, 15/60, 5/60], stress=[1, 2, 4])