Damping assessment and improving design of blade shrouds based on contact states

Damping assessment and improving design of a certain type of shrouded blades were conducted by applying the damping design method of sawtooth shroud based on contact states. Contact states included contact forms and contact parameters, in which contact forms could be used to judge the rationality of structure design; while contact parameters could be applied to evaluate the damping effect according to their mechanical properties. By generally assessing and analyzing the dynamic characteristics, contact states and dynamic response of the blade, the deficiencies of shroud structure design were found, and then the optimization measures which contributed to improve the contact states and dynamic response of the shroud were also proposed, also the stable operation range of chord width was obtained. The contact states could reflect the real contact conditions of shrouds when they are working, which can be regarded as a more accurate and detailed criterion for designing shroud structure and judging damping effects.