THERMAL SCIENCE

International Scientific Journal

Authors of this Paper

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Pan Li

,

Lihua Cao

,

Heyong Si

,

Wenlong Wang

INVESTIGATION ON THE UNSTEADY PRESSURE FLUCTUATION CHARACTERISTIC IN THE BLADE TIP SEAL OF STEAM TURBINE BASED ON SPECTRUM

ABSTRACT
The paper presents the unsteady numerical simulation results of tip leakage flow in high pressure steam turbines, and also presents the influence analysis of leakage vortexes on pressure fluctuation characteristics of rotor cascade under different blade tip seal clearances. The numerical method for calculating is based on the large eddy simulation turbulence model and the pressure fluctuation of rotor cascade which induced by the unstable leakage vortexes is obtained by frequency spectrum analysis. The results show that the vortex frequencies in tip seal cavity contain both the wheel rotating frequency and the high frequency caused by the tip leakage flow breaking into small scale vortexes. The unsteady characteristics of tip leakage flow also induce steam exciting force which changes with the time.
KEYWORDS
steam turbine, tip leakage vortex, pressure fluctuation, steam exciting force, large eddy simulation
PAPER SUBMITTED: 2019-03-08
PAPER REVISED: 2020-01-17
PAPER ACCEPTED: 2020-01-18
PUBLISHED ONLINE: 2020-02-08
DOI REFERENCE: https://doi.org/10.2298/TSCI190308053L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2020, VOLUME 24, ISSUE Issue 6, PAGES [3823 - 3834]
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Investigation on the unsteady pressure fluctuation characteristic in the blade tip seal of steam turbine based on spectrum

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