Influence of the steam within seals and glands of the turbine on its rotor motion stability

Abstract

In the paper assumptions for turbine seal modelling as well as the calculation results of the motion stability of a great-output turbo-set rotor are presented. The flow equation system was solved by using the linear perturbation method. On calculation of pressure distribution in the seal chambers it was possible to estimate values of the forces affecting the rotor in the seals. Problems of turbo-set rotor dynamics were solved with the use of the transfer matrix method where influences of partial turbo-set systems (bearing oil film, foundation, turbine seals) were modeled by dynamic characteristics dependent on rotor rotational speed and vibration frequency The theoretical results were partly confirmed by experimental investigations. The calculation results presented in the paper have been a part of the more thorough analysis of the great-output, energy-plant turbo-set [17,18].