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Research Papers: Gas Turbines: Turbomachinery

Investigation of Energy Loss on Fractional Deposition in Last Stages of Condensing Steam Turbine Due to Blade Shape and Moisture Droplet Size

[+] Author and Article Information
Bidesh Sengupta

Assistant Professor,
Modern Institute of Engineering
& Technology,
Hooghly 712123, West Bengal, India
e-mail: bideshsengupta.08@gmail.com

Chittatosh Bhattacharya

Associate Professor,
National Power Training Institute,
Durgapur 713216, West Bengal, India
e-mail: chittatoshbhattacharya@asme.org

1Corresponding author.

Contributed by the Turbomachinery Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received June 11, 2017; final manuscript received October 12, 2017; published online April 12, 2018. Assoc. Editor: Klaus Dobbeling.

J. Eng. Gas Turbines Power 140(7), 072601 (Apr 12, 2018) (8 pages) Paper No: GTP-17-1214; doi: 10.1115/1.4038544 History: Received June 11, 2017; Revised October 12, 2017

The steam consumption in a turbine within an operating pressure range determines the effectiveness of thermal energy conversion to electric power generation in a turbo-alternator. The low pressure (LP) stage of the steam turbine produces largest amount of steam to shaft-power in comparison to other stages of turbine although susceptible to various additional losses due to condensation of wet steam near penultimate and ultimate stages. The surface deposition in blade is caused by inertial impaction and turbulent-diffusion. With increasing blade stagger angle along the larger diameter of blading, the fractional deposition of wet steam is largely influenced by blade shape. From this background, the aim of this work is to predict the effect of mathematical models through computational fluid dynamics analysis on the characterization of thermodynamic and mechanical loss components based on unsaturated vapor water droplet size and pressure zones in LP stages of steam turbine and to investigate the influence of droplet size and rotor blade profile on cumulative energy losses due to condensation and provide an indication about the possible conceptual optimization of blade profile design to minimize moisture-induced energy losses.

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References

White, A. J. , Young, J. B. , and Walters, P. T. , 1996, “Experimental Validation of Condensing Flow Theory for a Stationary Cascade of Steam Turbine Blade,” Philos. Trans. R. Soc. London, 354(1704), pp. 59–88. [CrossRef]
Bakhtar, F. , Ebrahimi, M. , and Bamkole, B. , 1995, “On the Performance of a Cascade of Turbine Rotor Tip Section Blading in Nucleating Steam,” Proc. Inst. Mech. Eng.: J. Mech. Eng. Sci., 209(3), pp. 169–177. [CrossRef]
Bakhtar, F. , Ebrahimi, M. , and Webb, R. , 1995, “On the Performance of a Cascade of Turbine Rotor Tip Section Blading in Nucleating Steam—Part 1: Surface Pressure Distributions,” Proc. Inst. Mech. Eng. Part C, 209(2), pp. 115–124. [CrossRef]
White, A. J. , and Young, J. B. , 1993, “Time-Marching Method for the Prediction of Two-Dimensional Unsteady Flows of Condensing Steam,” AIAA J. Propul. Power, 9(4), pp. 579–587. [CrossRef]
Bakhtar, F. , Mahpeykar, M. R. , and Abbas, K. K. , 1995, “An Investigation of Nucleating Flows of Steam in a Cascade of Turbine Blading Theoretical Treatment,” ASME J. Fluids Eng., 117(1), pp. 138–144. [CrossRef]
Friedlander, S. K. , and Johnstone, H. F. , 1957, “Deposition of Suspended Particles From Turbulent Gas Streams,” Ind. Eng. Chem., 49(7), pp. 1151–1156. [CrossRef]
Montgomery, T. L. , and Corn, M. , 1970, “Aerosol Deposition in a Pipe With Turbulent Air Flow,” J. Aerosol Sci., 1(3), pp. 185–213. [CrossRef]
Liu, B. Y. H. , and Agarwal, J. K. , 1974, “Experimental Observation of Aerosol Deposition in Turbulent Flow,” J. Aerosol Sci., 5(2), pp. 145–155. [CrossRef]
Cleaver, J. W. , and Yates, B. , 1975, “A Sub-Layer Model for the Deposition of Particles From a Turbulent Flow,” Chem. Eng. Sci., 30(8), pp. 983–992. [CrossRef]
Gyarmathy, G. , 1962, “Bases of a Theory for Wet Steam Turbines,” CEGB Translation T-781, Federal Technical University, Zurich, Switzerland, Bulletin No. 6.
Crane, R. , 2004, “Droplet Deposition in Steam Turbines,” Proc. Inst. Mech. Eng., Part C, 218(8), pp. 859–870. [CrossRef]
Yau, K. , and Young, J. , 1987, “The Deposition of Fog Droplets on Steam Turbine Blades by Turbulent Diffusion,” ASME J. Turbomach., 109(3), pp. 429–435. [CrossRef]
Young, J. , and Yau, K. , 1988, “The Inertial Deposition of Fog Droplets on Steam Turbine Blades,” ASME J. Turbomach., 110(2), pp. 155–162. [CrossRef]
Sengupta, B. , and Bhattacharya, C. , 2017, “Influence of Blade Shape and Water Droplet Size on Fractional Deposition in the Last Stages of Steam Turbine,” Int. J. Emerging Technol. Adv. Eng., 7(4), pp. 164–172. http://www.ijetae.com/files/Volume7Issue4/IJETAE_0417_30.pdf
Kawagishi, H. , Onoda, A. , Shibukawa, N. , and Niizeki, Y. , 2011, “Development of Moisture Loss Models in Steam Turbines,” Heat Transfer-Asian Res., 42(7), pp. 651–664. [CrossRef]
Yu, X. , Xiao, Z. , Xie, D. , Wang, C. , and Wang, C. , 2015, “A 3D Method to Evaluate Moisture Losses in a Low Pressure Steam Turbine: Application to a Last Stage,” Int. J. Heat Mass Transfer, 84, pp. 642–652. [CrossRef]
Bakhtar, F. , Young, J. B. , White, A. J. , and Simpson, D. A. , 2005, “Classical Nucleation Theory and Its Application to Condensing Steam Flow Calculations,” J. Mech. Eng. Sci., 219(2), pp. 1315–1333. [CrossRef]
Gerber, A. G. , 2008, “Inhomogeneous Multifluid Model for Prediction of Nonequilibrium Phase Transition and Droplet Dynamics,” ASME J. Fluids Eng., 130(3), p. 031402.
Ryley, D. , and Parker, G. , 1967, “The Removal of Water From Low-Pressure Steam Turbine Blades by Trailing-Edge Suction Slots,” Proc. Inst. Mech. Eng., Conf. Proc., 182(8), pp. 94–103.
Ryley, D. , and Al-Azzawi, H. , 1983, “Suppression of the Deposition of Nucleated Fog Droplets on Steam Turbine Stator Blades by Blade Heating,” Int. J. Heat Fluid Flow, 4(4), pp. 207–216.

Figures

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Fig. 1:

Wet steam in LP stage of steam turbine [15]

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Fig. 2

Aspect of energy losses due to condensing moisture [15]

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Fig. 3

h-s diagram of condensation [15]

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Fig. 6

Thermodynamic loss on suction surface

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Fig. 7

Drag loss on pressure surface

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Fig. 8

Drag loss on suction surface

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Fig. 9

Number of moisture droplets

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Fig. 10

Number of liquid droplets for droplet radius R1

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Fig. 11

Capture loss on pressure surface

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Fig. 12

Capture loss on suction surface

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Fig. 4

(a) Total fractional deposition on pressure surface [14] and (b) total fractional deposition on suction surface [14]

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Fig. 5

Thermodynamic loss on pressure surface

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