Prevention of Steam Turbine Blade Erosion Using Stator Blade Heating

1977 ◽  
Vol 191 (1) ◽  
pp. 355-361 ◽  
Author(s):  
M.S. Akhtar ◽  
J. Black ◽  
M.J.C. Swainston
Keyword(s):  
Steam Turbine ◽  
Turbine Blade ◽  
Economic Effects ◽  
Steam Turbines ◽  
Reduced Pressure ◽  
Full Size ◽  
Basic Physics ◽  
Steam Turbine Blade ◽  
Stator Blade ◽  
Turbine Exhaust

Previous work on the phenomenon of the erosion of the moving blades in steam turbines is reviewed, which has shown that this is due to the accumulation of coarse water on the stationary blades. The basic physics of the accumulation is considered and the conclusion is drawn that this is due to condensation. This can occur even on adiabatic blading, but is expected to be particularly prevalent on blades whose interior is at a reduced pressure (and hence temperature) for suction purposes. Tests are reported on the heating of a single blade mounted in a steam tunnel downstream of a small steam turbine. The turbine exhaust could be arranged to be either wet or superheated. These tests showed that condensation on the blade could be prevented using only small amounts of heating. Methods of applying this system to full size turbines are considered and preliminary economic effects estimated, with encouraging results.

Improvement of Steam Turbine Blade Foil With Biomimetic Design and its Influence on Aerodynamic Performance

2019 ◽  
Author(s):  
Fan Wu ◽  
Danmei Xie ◽  
Jing Zhang ◽  
Hengliang Zhang ◽  
Chun Wang
Keyword(s):  
Steam Turbine ◽  
Turbine Blade ◽  
Vortex Pair ◽  
Separated Flow ◽  
Aerodynamic Performance ◽  
Steam Turbines ◽  
Structure Amplitude ◽  
Blade Shape ◽  
Steam Turbine Blade ◽  
Flow Vortex

Abstract To improve the steam turbines’ efficiency, researchers have put their efforts on blade foil design. Aiming at improve the aerodynamic performance of steam turbine at low load, this paper will study the effect of blade foil with bionics design on steam turbine aerodynamic performance, based on humpback whale’s fin. This paper mainly discusses a bionic foil design used on steam turbine. There are three main control parameters for each tubercle structure — amplitude, wavelength, and thickness. Taking the axial torque as the decisive consideration data and combining the vorticity diagram to analyze the flow, and on this basis, the influence of the vortex pair on the flow of the turbine blade is studied. The greater the torque, the stronger the function, so the steam turbines’ efficiency is higher. The flow condition of the optimized blade shape is improved compared to the original blade shape because it fits the blade more closely and the separated flow vortex is suppressed.

scholarly journals Failure Analysis in Lacing Wire Of Last Stage Low Pressure Steam Turbine Blade

2021 ◽  
Vol 1096 (1) ◽  
pp. 012097
Author(s):  
A M Kongkong ◽  
H Setiawan ◽  
J Miftahul ◽  
A R Laksana ◽  
I Djunaedi ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Steam Turbine ◽  
Turbine Blade ◽  
Low Pressure ◽  
Pressure Steam ◽  
Steam Turbine Blade ◽  
Last Stage

Studies on Determination of Natural Frequencies of Industrial Turbine Blades

1995 ◽  
Author(s):  
Mahesh M. Bhat ◽  
V. Ramamurti ◽  
C. Sujatha
Keyword(s):  
Steam Turbine ◽  
Dynamic Behavior ◽  
Turbine Blade ◽  
Natural Frequencies ◽  
Complex Structure ◽  
Turbine Blades ◽  
Blade Root ◽  
Steam Turbine Blade ◽  
Manufacturing Tolerances

Abstract Steam turbine blade is a very complex structure. It has geometric complexities like variation of twist, taper, width and thickness along its length. Most of the time these variations are not uniform. Apart from these geometric complexities, the blades are coupled by means of lacing wire, lacing rod or shroud. Blades are attached to a flexible disc which contributes to the dynamic behavior of the blade. Root fixity also plays an important role in this behavior. There is a considerable variation in the frequencies of blades of newly assembled turbine and frequencies after some hours of running. Again because of manufacturing tolerances there can be some variation in the blade to blade frequencies. Determination of natural frequencies of the blade is therefore a very critical job. Problems associated with typical industrial turbine bladed discs of a 235 MW steam turbine are highlighted in this paper.

Failure analysis of the 350MW steam turbine blade root

2009 ◽  
Vol 16 (4) ◽  
pp. 1270-1281 ◽  
Author(s):  
J. Kubiak Sz ◽  
J.A. Segura ◽  
G. Gonzalez R ◽  
J.C. García ◽  
F. Sierra E ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Steam Turbine ◽  
Turbine Blade ◽  
Blade Root ◽  
Steam Turbine Blade

The Effect of Stage-Diffuser Interaction on the Aerodynamic Performance and Design of LP Steam Turbine Exhaust Systems

2018 ◽  
Author(s):  
Bowen Ding ◽  
Liping Xu ◽  
Jiandao Yang ◽  
Rui Yang ◽  
Yuejin Dai
Keyword(s):  
Steam Turbine ◽  
Renewable Energy Sources ◽  
Rotor Blades ◽  
Steam Turbines ◽  
Flow Conditions ◽  
Part Load ◽  
Last Stage ◽  
Load Conditions ◽  
Turbine Exhaust ◽  
Exhaust Systems

Modern large steam turbines for power generation are required to operate much more flexibly than ever before, due to the increasing use of intermittent renewable energy sources such as solar and wind. This has posed great challenges to the design of LP steam turbine exhaust systems, which are critical to recovering the leaving energy that is otherwise lost. In previous studies, the design had been focused on the exhaust diffuser with or without the collector. Although the interaction between the last stage and the exhaust hood has been identified for a long time, little attention has been paid to the last stage blading in the exhaust system’s design process, when the machine frequently operates at part-load conditions. This study focuses on the design of LP exhaust systems considering both the last stage and the exhaust diffuser, over a wide operating range. A 1/10th scale air test rig was built to validate the CFD tool for flow conditions representative of an actual machine at part-load conditions, characterised by highly swirling flows entering the diffuser. A numerical parametric study was performed to investigate the effect of both the diffuser geometry variation and restaggering the last stage rotor blades. Restaggering the rotor blades was found to be an effective way to control the level of leaving energy, as well as the flow conditions at the diffuser inlet, which influence the diffuser’s capability to recover the leaving energy. The benefits from diffuser resizing and rotor blade restaggering were shown to be relatively independent of each other, which suggests the two components can be designed separately. Last, the potentials of performance improvement by considering both the last stage rotor restaggering and the diffuser resizing were demonstrated by an exemplary design, which predicted an increase in the last stage power output of at least 1.5% for a typical 1000MW plant that mostly operates at part-load conditions.

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