TJ205 :
Thesis > Central Library of Shahrood University > Mechanical Engineering > MSc > 2011
Authors:
Abstarct: We consider a variable thickness rotating disks under the temperature gradient and the magnetic field. Centrifugal force of rotation and temperature gradient are causes thermal and mechanical stresses in the disk.
In this study initially is determined most appropriate structure and thickness of the disk volume distribution, Then, according to Norton law, Magneto-thermo-elastic creep in the disc will be projected during the next fifty years. For this analysis, we get the equilibrium equations, relationship stress-strain and stress distribution is the solution. On The results relationships; values of creep strain are a function of creep strain and Creep strain in turn depend on temperature, stress and time. Therefore the classification of the radius into small unit using a numerical method, the calculated Temperature gradient and elastic stresses, the creep strain baxsed on the equations Prandtl-Reuss and effective stress can be calculated.
In this numerical method, the time component is selected, and then the strain of creeping into all parts of the disk radius can be guessed, with the small amounts of strain and solve equations balance, relationship stress - strain, stress values are calculated. With tension values, baxsed on the criteria von-Mises effective stress is calculated, then the creep strain rate equations baxsed on Prandtl-Reuss will be calculated.
With the creep strain rate and the amount of time considered, are measured in micro units of strain creep And these values as new values for the iterations to achieve convergence will be taken.
The total creep strains, sum of small units of creep strain have been converging that are used in calculating the stresses and dislocation creep.
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