Experimental and numerical study on pressure losses and flow fluctuations in a high-pressure valve assembly of steam turbine governing system

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388998%3A_____%2F20%3A00537768" target="_blank" >RIV/61388998:_____/20:00537768 - isvavai.cz</a>

Alternative codes found

RIV/49193864:_____/20:N0000004

Result on the web

<a href="https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2020/84201/V009T23A007/1095204" target="_blank" >https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2020/84201/V009T23A007/1095204</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1115/GT2020-14474" target="_blank" >10.1115/GT2020-14474</a>

Result language

angličtina

Original language name

Experimental and numerical study on pressure losses and flow fluctuations in a high-pressure valve assembly of steam turbine governing system

Original language description

Aerodynamic measurements and numerical simulations carried out on a model of a high-pressure valve assembly used for nozzle governing of a turbine with 135MW output are described in this paper. Aim of the study is to investigate effects of control valve's strainers on pressure losses and unsteadiness in the flow field. It is an important task since undesirable flow fluctuations can lead to operational reliability issues. Measurements were carried out in the Aerodynamic laboratory of the Institute of Thermomechanics of the Czech Academy of Sciences (IT) where an aerodynamic tunnel is installed. Numerical simulations were carried out in the Doosan Skoda Power (DSP) Company using ANSYS software tools. The experimental model consists of one of two identical parts of the real valve assembly. It means it consists of an inlet pipeline, a stop valve, a valve chamber with two independent control valves, its diffusers and outlet pipelines. The numerical model consists of both assembly parts and includes also an A-wheel control stage in order to simulate the real turbine operating points. The different lifts of the main cone in each control valve for its useful combinations were investigated. Results were evaluated on the model with control valve´s strainers, which were historically used in order to stabilize the flow, and without them. The results of the experimental measurement were compared with the numerical results in the form of pressure losses prediction. From measured pressure fluctuations, it was found out where and for which conditions a danger of flow instabilities occurs. It can be concluded that there is a border, in terms of operating conditions, where the flow field starts to be unstable and this border is different dependent of the fact whether the control valve´s strainers are used or not. Therefore, the areas of safe and danger operational reliability can be predicted. The influence of the control valve´s strainers on the maximal amplitude of periodic fluctuations appears only for the cases when valves are highly overloaded. For normal operating conditions, there is no difference. As a result, the control valve´s strainers do not have to be used in standard applications of valve assemblies. Furthermore, a loss model for valve pressure loss estimation could be updated. Therefore, a pressure loss should be predicted with a sufficient accuracy for each new turbine bid with similar valve assemblies.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

—

OECD FORD branch

20302 - Applied mechanics

Project

<a href="/en/project/TN01000007" target="_blank" >TN01000007: National Centre for Energy</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

Proceedings of the ASME Turbo Expo

ISBN

978-0-7918-8420-1

ISSN

—

e-ISSN

—

Number of pages

11

Pages from-to

V009T23A007

Publisher name

American Society of Mechanical Engineers (ASME)

Place of publication

Virtual, Online

Event location

Virtual, Online

Event date

Sep 21, 2020

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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