ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
An important characteristic of a steam power plant is its ability to maintain reliability andsafety of the plant against frequent start-ups and load changes. Transient regimes arising duringstart-ups, shut-downs and load changes give rise to unsteady temperature distribution with time insteam turbine rotor(HP/IP), which results in non-uniform strain and stress distribution. The rapidincrease of temperature and rotational speed during starts-ups, especially, makes conditions moresevere and causes main components’ damage and reduction of life span for steam turbine. Thusaccurate knowledge of thermal and centrifugal stresses are required for the integrity and lifetimeassessment for the turbine rotor. So far, only elastic calculations are currently performed forsimplicity. However, it is well known that the materials of steam turbine rotor deform inelasticallyat high temperature. Existing models proposed to describe the viscoplastic(rate-dependent) behaviorare rather elaborate and difficult to incorporate with computer simulations in the case of complexstructures. In this paper, the life assessment for steam turbine rotor was established by combiningthe inelastic behavior and the finite element method. The inelastic analysis was particularly focusedon viscoplastic behavior that is simple enough to be used effectively in computer simulation andmatches the essential features of the time-dependent inelastic behavior of materials reasonably wellfor cyclic loading under non-isothermal conditions. Using this study, life consumption of steamturbine rotor can be obtained
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.326-328.601.pdf
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